Adds an option to the strings program to specify a separator between the emitted...
[deliverable/binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2015 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nlmconv: (binutils)nlmconv. Converts object code into an NLM.
38 * nm: (binutils)nm. List symbols from object files.
39 * objcopy: (binutils)objcopy. Copy and translate object files.
40 * objdump: (binutils)objdump. Display information from object files.
41 * ranlib: (binutils)ranlib. Generate index to archive contents.
42 * readelf: (binutils)readelf. Display the contents of ELF format files.
43 * size: (binutils)size. List section sizes and total size.
44 * strings: (binutils)strings. List printable strings from files.
45 * strip: (binutils)strip. Discard symbols.
46 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
47 * windmc: (binutils)windmc. Generator for Windows message resources.
48 * windres: (binutils)windres. Manipulate Windows resources.
49 @end direntry
50
51 @titlepage
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
55 @end ifset
56 @subtitle Version @value{VERSION}
57 @sp 1
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
62 @page
63
64 @tex
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
67 @end tex
68
69 @vskip 0pt plus 1filll
70 @insertcopying
71 @end titlepage
72 @contents
73
74 @node Top
75 @top Introduction
76
77 @cindex version
78 This brief manual contains documentation for the @sc{gnu} binary
79 utilities
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
82 @end ifset
83 version @value{VERSION}:
84
85 @iftex
86 @table @code
87 @item ar
88 Create, modify, and extract from archives
89
90 @item nm
91 List symbols from object files
92
93 @item objcopy
94 Copy and translate object files
95
96 @item objdump
97 Display information from object files
98
99 @item ranlib
100 Generate index to archive contents
101
102 @item readelf
103 Display the contents of ELF format files.
104
105 @item size
106 List file section sizes and total size
107
108 @item strings
109 List printable strings from files
110
111 @item strip
112 Discard symbols
113
114 @item elfedit
115 Update the ELF header of ELF files.
116
117 @item c++filt
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
119 @code{cxxfilt})
120
121 @item addr2line
122 Convert addresses into file names and line numbers
123
124 @item nlmconv
125 Convert object code into a Netware Loadable Module
126
127 @item windres
128 Manipulate Windows resources
129
130 @item windmc
131 Generator for Windows message resources
132
133 @item dlltool
134 Create the files needed to build and use Dynamic Link Libraries
135 @end table
136 @end iftex
137
138 This document is distributed under the terms of the GNU Free
139 Documentation License version 1.3. A copy of the license is included
140 in the section entitled ``GNU Free Documentation License''.
141
142 @menu
143 * ar:: Create, modify, and extract from archives
144 * nm:: List symbols from object files
145 * objcopy:: Copy and translate object files
146 * objdump:: Display information from object files
147 * ranlib:: Generate index to archive contents
148 * size:: List section sizes and total size
149 * strings:: List printable strings from files
150 * strip:: Discard symbols
151 * c++filt:: Filter to demangle encoded C++ symbols
152 * cxxfilt: c++filt. MS-DOS name for c++filt
153 * addr2line:: Convert addresses to file and line
154 * nlmconv:: Converts object code into an NLM
155 * windmc:: Generator for Windows message resources
156 * windres:: Manipulate Windows resources
157 * dlltool:: Create files needed to build and use DLLs
158 * readelf:: Display the contents of ELF format files
159 * elfedit:: Update the ELF header of ELF files
160 * Common Options:: Command-line options for all utilities
161 * Selecting the Target System:: How these utilities determine the target
162 * Reporting Bugs:: Reporting Bugs
163 * GNU Free Documentation License:: GNU Free Documentation License
164 * Binutils Index:: Binutils Index
165 @end menu
166
167 @node ar
168 @chapter ar
169
170 @kindex ar
171 @cindex archives
172 @cindex collections of files
173
174 @c man title ar create, modify, and extract from archives
175
176 @smallexample
177 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
178 ar -M [ <mri-script ]
179 @end smallexample
180
181 @c man begin DESCRIPTION ar
182
183 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
187
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
190 extraction.
191
192 @cindex name length
193 @sc{gnu} @command{ar} can maintain archives whose members have names of any
194 length; however, depending on how @command{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
199
200 @cindex libraries
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
203 subroutines.
204
205 @cindex symbol index
206 @command{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @command{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
213
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @command{ar} called
216 @command{ranlib} can be used to add just the table.
217
218 @cindex thin archives
219 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
220 which contains a symbol index and references to the original copies
221 of the member files of the archive. This is useful for building
222 libraries for use within a local build tree, where the relocatable
223 objects are expected to remain available, and copying the contents of
224 each object would only waste time and space.
225
226 An archive can either be @emph{thin} or it can be normal. It cannot
227 be both at the same time. Once an archive is created its format
228 cannot be changed without first deleting it and then creating a new
229 archive in its place.
230
231 Thin archives are also @emph{flattened}, so that adding one thin
232 archive to another thin archive does not nest it, as would happen with
233 a normal archive. Instead the elements of the first archive are added
234 individually to the second archive.
235
236 The paths to the elements of the archive are stored relative to the
237 archive itself.
238
239 @cindex compatibility, @command{ar}
240 @cindex @command{ar} compatibility
241 @sc{gnu} @command{ar} is designed to be compatible with two different
242 facilities. You can control its activity using command-line options,
243 like the different varieties of @command{ar} on Unix systems; or, if you
244 specify the single command-line option @option{-M}, you can control it
245 with a script supplied via standard input, like the MRI ``librarian''
246 program.
247
248 @c man end
249
250 @menu
251 * ar cmdline:: Controlling @command{ar} on the command line
252 * ar scripts:: Controlling @command{ar} with a script
253 @end menu
254
255 @page
256 @node ar cmdline
257 @section Controlling @command{ar} on the Command Line
258
259 @smallexample
260 @c man begin SYNOPSIS ar
261 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
262 @c man end
263 @end smallexample
264
265 @cindex Unix compatibility, @command{ar}
266 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
267 arguments to execute: one keyletter specifying the @emph{operation}
268 (optionally accompanied by other keyletters specifying
269 @emph{modifiers}), and the archive name to act on.
270
271 Most operations can also accept further @var{member} arguments,
272 specifying particular files to operate on.
273
274 @c man begin OPTIONS ar
275
276 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
277 flags @var{mod} in any order, within the first command-line argument.
278
279 If you wish, you may begin the first command-line argument with a
280 dash.
281
282 @cindex operations on archive
283 The @var{p} keyletter specifies what operation to execute; it may be
284 any of the following, but you must specify only one of them:
285
286 @table @samp
287 @item d
288 @cindex deleting from archive
289 @emph{Delete} modules from the archive. Specify the names of modules to
290 be deleted as @var{member}@dots{}; the archive is untouched if you
291 specify no files to delete.
292
293 If you specify the @samp{v} modifier, @command{ar} lists each module
294 as it is deleted.
295
296 @item m
297 @cindex moving in archive
298 Use this operation to @emph{move} members in an archive.
299
300 The ordering of members in an archive can make a difference in how
301 programs are linked using the library, if a symbol is defined in more
302 than one member.
303
304 If no modifiers are used with @code{m}, any members you name in the
305 @var{member} arguments are moved to the @emph{end} of the archive;
306 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
307 specified place instead.
308
309 @item p
310 @cindex printing from archive
311 @emph{Print} the specified members of the archive, to the standard
312 output file. If the @samp{v} modifier is specified, show the member
313 name before copying its contents to standard output.
314
315 If you specify no @var{member} arguments, all the files in the archive are
316 printed.
317
318 @item q
319 @cindex quick append to archive
320 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
321 @var{archive}, without checking for replacement.
322
323 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
324 operation; new members are always placed at the end of the archive.
325
326 The modifier @samp{v} makes @command{ar} list each file as it is appended.
327
328 Since the point of this operation is speed, implementations of
329 @command{ar} have the option of not updating the archive's symbol
330 table if one exists. Too many different systems however assume that
331 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
332 rebuild the table even with a quick append.
333
334 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
335 synonym for @samp{r} - replacing already existing files in the
336 archive and appending new ones at the end.
337
338 @item r
339 @cindex replacement in archive
340 Insert the files @var{member}@dots{} into @var{archive} (with
341 @emph{replacement}). This operation differs from @samp{q} in that any
342 previously existing members are deleted if their names match those being
343 added.
344
345 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
346 displays an error message, and leaves undisturbed any existing members
347 of the archive matching that name.
348
349 By default, new members are added at the end of the file; but you may
350 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
351 placement relative to some existing member.
352
353 The modifier @samp{v} used with this operation elicits a line of
354 output for each file inserted, along with one of the letters @samp{a} or
355 @samp{r} to indicate whether the file was appended (no old member
356 deleted) or replaced.
357
358 @item s
359 @cindex ranlib
360 Add an index to the archive, or update it if it already exists. Note
361 this command is an exception to the rule that there can only be one
362 command letter, as it is possible to use it as either a command or a
363 modifier. In either case it does the same thing.
364
365 @item t
366 @cindex contents of archive
367 Display a @emph{table} listing the contents of @var{archive}, or those
368 of the files listed in @var{member}@dots{} that are present in the
369 archive. Normally only the member name is shown; if you also want to
370 see the modes (permissions), timestamp, owner, group, and size, you can
371 request that by also specifying the @samp{v} modifier.
372
373 If you do not specify a @var{member}, all files in the archive
374 are listed.
375
376 @cindex repeated names in archive
377 @cindex name duplication in archive
378 If there is more than one file with the same name (say, @samp{fie}) in
379 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
380 first instance; to see them all, you must ask for a complete
381 listing---in our example, @samp{ar t b.a}.
382 @c WRS only; per Gumby, this is implementation-dependent, and in a more
383 @c recent case in fact works the other way.
384
385 @item x
386 @cindex extract from archive
387 @emph{Extract} members (named @var{member}) from the archive. You can
388 use the @samp{v} modifier with this operation, to request that
389 @command{ar} list each name as it extracts it.
390
391 If you do not specify a @var{member}, all files in the archive
392 are extracted.
393
394 Files cannot be extracted from a thin archive.
395
396 @item --help
397 Displays the list of command line options supported by @command{ar}
398 and then exits.
399
400 @item --version
401 Displays the version information of @command{ar} and then exits.
402
403 @end table
404
405 A number of modifiers (@var{mod}) may immediately follow the @var{p}
406 keyletter, to specify variations on an operation's behavior:
407
408 @table @samp
409 @item a
410 @cindex relative placement in archive
411 Add new files @emph{after} an existing member of the
412 archive. If you use the modifier @samp{a}, the name of an existing archive
413 member must be present as the @var{relpos} argument, before the
414 @var{archive} specification.
415
416 @item b
417 Add new files @emph{before} an existing member of the
418 archive. If you use the modifier @samp{b}, the name of an existing archive
419 member must be present as the @var{relpos} argument, before the
420 @var{archive} specification. (same as @samp{i}).
421
422 @item c
423 @cindex creating archives
424 @emph{Create} the archive. The specified @var{archive} is always
425 created if it did not exist, when you request an update. But a warning is
426 issued unless you specify in advance that you expect to create it, by
427 using this modifier.
428
429 @item D
430 @cindex deterministic archives
431 @kindex --enable-deterministic-archives
432 Operate in @emph{deterministic} mode. When adding files and the archive
433 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
434 for all files. When this option is used, if @command{ar} is used with
435 identical options and identical input files, multiple runs will create
436 identical output files regardless of the input files' owners, groups,
437 file modes, or modification times.
438
439 If @file{binutils} was configured with
440 @option{--enable-deterministic-archives}, then this mode is on by default.
441 It can be disabled with the @samp{U} modifier, below.
442
443 @item f
444 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
445 names of any length. This will cause it to create archives which are
446 not compatible with the native @command{ar} program on some systems. If
447 this is a concern, the @samp{f} modifier may be used to truncate file
448 names when putting them in the archive.
449
450 @item i
451 Insert new files @emph{before} an existing member of the
452 archive. If you use the modifier @samp{i}, the name of an existing archive
453 member must be present as the @var{relpos} argument, before the
454 @var{archive} specification. (same as @samp{b}).
455
456 @item l
457 This modifier is accepted but not used.
458 @c whaffor ar l modifier??? presumably compat; with
459 @c what???---doc@@cygnus.com, 25jan91
460
461 @item N
462 Uses the @var{count} parameter. This is used if there are multiple
463 entries in the archive with the same name. Extract or delete instance
464 @var{count} of the given name from the archive.
465
466 @item o
467 @cindex dates in archive
468 Preserve the @emph{original} dates of members when extracting them. If
469 you do not specify this modifier, files extracted from the archive
470 are stamped with the time of extraction.
471
472 @item P
473 Use the full path name when matching names in the archive. @sc{gnu}
474 @command{ar} can not create an archive with a full path name (such archives
475 are not POSIX complaint), but other archive creators can. This option
476 will cause @sc{gnu} @command{ar} to match file names using a complete path
477 name, which can be convenient when extracting a single file from an
478 archive created by another tool.
479
480 @item s
481 @cindex writing archive index
482 Write an object-file index into the archive, or update an existing one,
483 even if no other change is made to the archive. You may use this modifier
484 flag either with any operation, or alone. Running @samp{ar s} on an
485 archive is equivalent to running @samp{ranlib} on it.
486
487 @item S
488 @cindex not writing archive index
489 Do not generate an archive symbol table. This can speed up building a
490 large library in several steps. The resulting archive can not be used
491 with the linker. In order to build a symbol table, you must omit the
492 @samp{S} modifier on the last execution of @samp{ar}, or you must run
493 @samp{ranlib} on the archive.
494
495 @item T
496 @cindex creating thin archive
497 Make the specified @var{archive} a @emph{thin} archive. If it already
498 exists and is a regular archive, the existing members must be present
499 in the same directory as @var{archive}.
500
501 @item u
502 @cindex updating an archive
503 Normally, @samp{ar r}@dots{} inserts all files
504 listed into the archive. If you would like to insert @emph{only} those
505 of the files you list that are newer than existing members of the same
506 names, use this modifier. The @samp{u} modifier is allowed only for the
507 operation @samp{r} (replace). In particular, the combination @samp{qu} is
508 not allowed, since checking the timestamps would lose any speed
509 advantage from the operation @samp{q}.
510
511 @item U
512 @cindex deterministic archives
513 @kindex --enable-deterministic-archives
514 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
515 of the @samp{D} modifier, above: added files and the archive index will
516 get their actual UID, GID, timestamp, and file mode values.
517
518 This is the default unless @file{binutils} was configured with
519 @option{--enable-deterministic-archives}.
520
521 @item v
522 This modifier requests the @emph{verbose} version of an operation. Many
523 operations display additional information, such as filenames processed,
524 when the modifier @samp{v} is appended.
525
526 @item V
527 This modifier shows the version number of @command{ar}.
528 @end table
529
530 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
531 compatibility with AIX. The behaviour produced by this option is the
532 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
533 @samp{-X} options; in particular, it does not support @option{-X32}
534 which is the default for AIX @command{ar}.
535
536 The optional command line switch @option{--plugin} @var{name} causes
537 @command{ar} to load the plugin called @var{name} which adds support
538 for more file formats. This option is only available if the toolchain
539 has been built with plugin support enabled.
540
541 The optional command line switch @option{--target} @var{bfdname}
542 specifies that the archive members are in an object code format
543 different from your system's default format. See
544 @xref{Target Selection}, for more information.
545
546 @c man end
547
548 @ignore
549 @c man begin SEEALSO ar
550 nm(1), ranlib(1), and the Info entries for @file{binutils}.
551 @c man end
552 @end ignore
553
554 @node ar scripts
555 @section Controlling @command{ar} with a Script
556
557 @smallexample
558 ar -M [ <@var{script} ]
559 @end smallexample
560
561 @cindex MRI compatibility, @command{ar}
562 @cindex scripts, @command{ar}
563 If you use the single command-line option @samp{-M} with @command{ar}, you
564 can control its operation with a rudimentary command language. This
565 form of @command{ar} operates interactively if standard input is coming
566 directly from a terminal. During interactive use, @command{ar} prompts for
567 input (the prompt is @samp{AR >}), and continues executing even after
568 errors. If you redirect standard input to a script file, no prompts are
569 issued, and @command{ar} abandons execution (with a nonzero exit code)
570 on any error.
571
572 The @command{ar} command language is @emph{not} designed to be equivalent
573 to the command-line options; in fact, it provides somewhat less control
574 over archives. The only purpose of the command language is to ease the
575 transition to @sc{gnu} @command{ar} for developers who already have scripts
576 written for the MRI ``librarian'' program.
577
578 The syntax for the @command{ar} command language is straightforward:
579 @itemize @bullet
580 @item
581 commands are recognized in upper or lower case; for example, @code{LIST}
582 is the same as @code{list}. In the following descriptions, commands are
583 shown in upper case for clarity.
584
585 @item
586 a single command may appear on each line; it is the first word on the
587 line.
588
589 @item
590 empty lines are allowed, and have no effect.
591
592 @item
593 comments are allowed; text after either of the characters @samp{*}
594 or @samp{;} is ignored.
595
596 @item
597 Whenever you use a list of names as part of the argument to an @command{ar}
598 command, you can separate the individual names with either commas or
599 blanks. Commas are shown in the explanations below, for clarity.
600
601 @item
602 @samp{+} is used as a line continuation character; if @samp{+} appears
603 at the end of a line, the text on the following line is considered part
604 of the current command.
605 @end itemize
606
607 Here are the commands you can use in @command{ar} scripts, or when using
608 @command{ar} interactively. Three of them have special significance:
609
610 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
611 a temporary file required for most of the other commands.
612
613 @code{SAVE} commits the changes so far specified by the script. Prior
614 to @code{SAVE}, commands affect only the temporary copy of the current
615 archive.
616
617 @table @code
618 @item ADDLIB @var{archive}
619 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
620 Add all the contents of @var{archive} (or, if specified, each named
621 @var{module} from @var{archive}) to the current archive.
622
623 Requires prior use of @code{OPEN} or @code{CREATE}.
624
625 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
626 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
627 @c else like "ar q..."
628 Add each named @var{member} as a module in the current archive.
629
630 Requires prior use of @code{OPEN} or @code{CREATE}.
631
632 @item CLEAR
633 Discard the contents of the current archive, canceling the effect of
634 any operations since the last @code{SAVE}. May be executed (with no
635 effect) even if no current archive is specified.
636
637 @item CREATE @var{archive}
638 Creates an archive, and makes it the current archive (required for many
639 other commands). The new archive is created with a temporary name; it
640 is not actually saved as @var{archive} until you use @code{SAVE}.
641 You can overwrite existing archives; similarly, the contents of any
642 existing file named @var{archive} will not be destroyed until @code{SAVE}.
643
644 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
645 Delete each listed @var{module} from the current archive; equivalent to
646 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
647
648 Requires prior use of @code{OPEN} or @code{CREATE}.
649
650 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
651 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
652 List each named @var{module} present in @var{archive}. The separate
653 command @code{VERBOSE} specifies the form of the output: when verbose
654 output is off, output is like that of @samp{ar -t @var{archive}
655 @var{module}@dots{}}. When verbose output is on, the listing is like
656 @samp{ar -tv @var{archive} @var{module}@dots{}}.
657
658 Output normally goes to the standard output stream; however, if you
659 specify @var{outputfile} as a final argument, @command{ar} directs the
660 output to that file.
661
662 @item END
663 Exit from @command{ar}, with a @code{0} exit code to indicate successful
664 completion. This command does not save the output file; if you have
665 changed the current archive since the last @code{SAVE} command, those
666 changes are lost.
667
668 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
669 Extract each named @var{module} from the current archive, writing them
670 into the current directory as separate files. Equivalent to @samp{ar -x
671 @var{archive} @var{module}@dots{}}.
672
673 Requires prior use of @code{OPEN} or @code{CREATE}.
674
675 @ignore
676 @c FIXME Tokens but no commands???
677 @item FULLDIR
678
679 @item HELP
680 @end ignore
681
682 @item LIST
683 Display full contents of the current archive, in ``verbose'' style
684 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
685 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
686 enhancement, rather than present for MRI compatibility.)
687
688 Requires prior use of @code{OPEN} or @code{CREATE}.
689
690 @item OPEN @var{archive}
691 Opens an existing archive for use as the current archive (required for
692 many other commands). Any changes as the result of subsequent commands
693 will not actually affect @var{archive} until you next use @code{SAVE}.
694
695 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
696 In the current archive, replace each existing @var{module} (named in
697 the @code{REPLACE} arguments) from files in the current working directory.
698 To execute this command without errors, both the file, and the module in
699 the current archive, must exist.
700
701 Requires prior use of @code{OPEN} or @code{CREATE}.
702
703 @item VERBOSE
704 Toggle an internal flag governing the output from @code{DIRECTORY}.
705 When the flag is on, @code{DIRECTORY} output matches output from
706 @samp{ar -tv }@dots{}.
707
708 @item SAVE
709 Commit your changes to the current archive, and actually save it as a
710 file with the name specified in the last @code{CREATE} or @code{OPEN}
711 command.
712
713 Requires prior use of @code{OPEN} or @code{CREATE}.
714
715 @end table
716
717 @iftex
718 @node ld
719 @chapter ld
720 @cindex linker
721 @kindex ld
722 The @sc{gnu} linker @command{ld} is now described in a separate manual.
723 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
724 @end iftex
725
726 @node nm
727 @chapter nm
728 @cindex symbols
729 @kindex nm
730
731 @c man title nm list symbols from object files
732
733 @smallexample
734 @c man begin SYNOPSIS nm
735 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
736 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
737 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
738 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
739 [@option{-l}|@option{--line-numbers}] [@option{-n}|@option{-v}|@option{--numeric-sort}]
740 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
741 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
742 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
743 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
744 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
745 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
746 [@option{--synthetic}] [@option{--target=}@var{bfdname}]
747 [@var{objfile}@dots{}]
748 @c man end
749 @end smallexample
750
751 @c man begin DESCRIPTION nm
752 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
753 If no object files are listed as arguments, @command{nm} assumes the file
754 @file{a.out}.
755
756 For each symbol, @command{nm} shows:
757
758 @itemize @bullet
759 @item
760 The symbol value, in the radix selected by options (see below), or
761 hexadecimal by default.
762
763 @item
764 The symbol type. At least the following types are used; others are, as
765 well, depending on the object file format. If lowercase, the symbol is
766 usually local; if uppercase, the symbol is global (external). There
767 are however a few lowercase symbols that are shown for special global
768 symbols (@code{u}, @code{v} and @code{w}).
769
770 @c Some more detail on exactly what these symbol types are used for
771 @c would be nice.
772 @table @code
773 @item A
774 The symbol's value is absolute, and will not be changed by further
775 linking.
776
777 @item B
778 @itemx b
779 The symbol is in the uninitialized data section (known as BSS).
780
781 @item C
782 The symbol is common. Common symbols are uninitialized data. When
783 linking, multiple common symbols may appear with the same name. If the
784 symbol is defined anywhere, the common symbols are treated as undefined
785 references.
786 @ifclear man
787 For more details on common symbols, see the discussion of
788 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
789 @end ifclear
790
791 @item D
792 @itemx d
793 The symbol is in the initialized data section.
794
795 @item G
796 @itemx g
797 The symbol is in an initialized data section for small objects. Some
798 object file formats permit more efficient access to small data objects,
799 such as a global int variable as opposed to a large global array.
800
801 @item i
802 For PE format files this indicates that the symbol is in a section
803 specific to the implementation of DLLs. For ELF format files this
804 indicates that the symbol is an indirect function. This is a GNU
805 extension to the standard set of ELF symbol types. It indicates a
806 symbol which if referenced by a relocation does not evaluate to its
807 address, but instead must be invoked at runtime. The runtime
808 execution will then return the value to be used in the relocation.
809
810 @item I
811 The symbol is an indirect reference to another symbol.
812
813 @item N
814 The symbol is a debugging symbol.
815
816 @item p
817 The symbols is in a stack unwind section.
818
819 @item R
820 @itemx r
821 The symbol is in a read only data section.
822
823 @item S
824 @itemx s
825 The symbol is in an uninitialized data section for small objects.
826
827 @item T
828 @itemx t
829 The symbol is in the text (code) section.
830
831 @item U
832 The symbol is undefined.
833
834 @item u
835 The symbol is a unique global symbol. This is a GNU extension to the
836 standard set of ELF symbol bindings. For such a symbol the dynamic linker
837 will make sure that in the entire process there is just one symbol with
838 this name and type in use.
839
840 @item V
841 @itemx v
842 The symbol is a weak object. When a weak defined symbol is linked with
843 a normal defined symbol, the normal defined symbol is used with no error.
844 When a weak undefined symbol is linked and the symbol is not defined,
845 the value of the weak symbol becomes zero with no error. On some
846 systems, uppercase indicates that a default value has been specified.
847
848 @item W
849 @itemx w
850 The symbol is a weak symbol that has not been specifically tagged as a
851 weak object symbol. When a weak defined symbol is linked with a normal
852 defined symbol, the normal defined symbol is used with no error.
853 When a weak undefined symbol is linked and the symbol is not defined,
854 the value of the symbol is determined in a system-specific manner without
855 error. On some systems, uppercase indicates that a default value has been
856 specified.
857
858 @item -
859 The symbol is a stabs symbol in an a.out object file. In this case, the
860 next values printed are the stabs other field, the stabs desc field, and
861 the stab type. Stabs symbols are used to hold debugging information.
862
863 @item ?
864 The symbol type is unknown, or object file format specific.
865 @end table
866
867 @item
868 The symbol name.
869 @end itemize
870
871 @c man end
872
873 @c man begin OPTIONS nm
874 The long and short forms of options, shown here as alternatives, are
875 equivalent.
876
877 @table @env
878 @item -A
879 @itemx -o
880 @itemx --print-file-name
881 @cindex input file name
882 @cindex file name
883 @cindex source file name
884 Precede each symbol by the name of the input file (or archive member)
885 in which it was found, rather than identifying the input file once only,
886 before all of its symbols.
887
888 @item -a
889 @itemx --debug-syms
890 @cindex debugging symbols
891 Display all symbols, even debugger-only symbols; normally these are not
892 listed.
893
894 @item -B
895 @cindex @command{nm} format
896 @cindex @command{nm} compatibility
897 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
898
899 @item -C
900 @itemx --demangle[=@var{style}]
901 @cindex demangling in nm
902 Decode (@dfn{demangle}) low-level symbol names into user-level names.
903 Besides removing any initial underscore prepended by the system, this
904 makes C++ function names readable. Different compilers have different
905 mangling styles. The optional demangling style argument can be used to
906 choose an appropriate demangling style for your compiler. @xref{c++filt},
907 for more information on demangling.
908
909 @item --no-demangle
910 Do not demangle low-level symbol names. This is the default.
911
912 @item -D
913 @itemx --dynamic
914 @cindex dynamic symbols
915 Display the dynamic symbols rather than the normal symbols. This is
916 only meaningful for dynamic objects, such as certain types of shared
917 libraries.
918
919 @item -f @var{format}
920 @itemx --format=@var{format}
921 @cindex @command{nm} format
922 @cindex @command{nm} compatibility
923 Use the output format @var{format}, which can be @code{bsd},
924 @code{sysv}, or @code{posix}. The default is @code{bsd}.
925 Only the first character of @var{format} is significant; it can be
926 either upper or lower case.
927
928 @item -g
929 @itemx --extern-only
930 @cindex external symbols
931 Display only external symbols.
932
933 @item -h
934 @itemx --help
935 Show a summary of the options to @command{nm} and exit.
936
937 @item -l
938 @itemx --line-numbers
939 @cindex symbol line numbers
940 For each symbol, use debugging information to try to find a filename and
941 line number. For a defined symbol, look for the line number of the
942 address of the symbol. For an undefined symbol, look for the line
943 number of a relocation entry which refers to the symbol. If line number
944 information can be found, print it after the other symbol information.
945
946 @item -n
947 @itemx -v
948 @itemx --numeric-sort
949 Sort symbols numerically by their addresses, rather than alphabetically
950 by their names.
951
952 @item -p
953 @itemx --no-sort
954 @cindex sorting symbols
955 Do not bother to sort the symbols in any order; print them in the order
956 encountered.
957
958 @item -P
959 @itemx --portability
960 Use the POSIX.2 standard output format instead of the default format.
961 Equivalent to @samp{-f posix}.
962
963 @item -r
964 @itemx --reverse-sort
965 Reverse the order of the sort (whether numeric or alphabetic); let the
966 last come first.
967
968 @item -S
969 @itemx --print-size
970 Print both value and size of defined symbols for the @code{bsd} output style.
971 This option has no effect for object formats that do not record symbol
972 sizes, unless @samp{--size-sort} is also used in which case a
973 calculated size is displayed.
974
975 @item -s
976 @itemx --print-armap
977 @cindex symbol index, listing
978 When listing symbols from archive members, include the index: a mapping
979 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
980 contain definitions for which names.
981
982 @item -t @var{radix}
983 @itemx --radix=@var{radix}
984 Use @var{radix} as the radix for printing the symbol values. It must be
985 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
986
987 @item -u
988 @itemx --undefined-only
989 @cindex external symbols
990 @cindex undefined symbols
991 Display only undefined symbols (those external to each object file).
992
993 @item -V
994 @itemx --version
995 Show the version number of @command{nm} and exit.
996
997 @item -X
998 This option is ignored for compatibility with the AIX version of
999 @command{nm}. It takes one parameter which must be the string
1000 @option{32_64}. The default mode of AIX @command{nm} corresponds
1001 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1002
1003 @item --defined-only
1004 @cindex external symbols
1005 @cindex undefined symbols
1006 Display only defined symbols for each object file.
1007
1008 @item --plugin @var{name}
1009 @cindex load plugin
1010 Load the plugin called @var{name} to add support for extra target
1011 types. This option is only available if the toolchain has been built
1012 with plugin support enabled.
1013
1014 @item --size-sort
1015 Sort symbols by size. The size is computed as the difference between
1016 the value of the symbol and the value of the symbol with the next higher
1017 value. If the @code{bsd} output format is used the size of the symbol
1018 is printed, rather than the value, and @samp{-S} must be used in order
1019 both size and value to be printed.
1020
1021 @item --special-syms
1022 Display symbols which have a target-specific special meaning. These
1023 symbols are usually used by the target for some special processing and
1024 are not normally helpful when included in the normal symbol lists.
1025 For example for ARM targets this option would skip the mapping symbols
1026 used to mark transitions between ARM code, THUMB code and data.
1027
1028 @item --synthetic
1029 Include synthetic symbols in the output. These are special symbols
1030 created by the linker for various purposes. They are not shown by
1031 default since they are not part of the binary's original source code.
1032
1033 @item --target=@var{bfdname}
1034 @cindex object code format
1035 Specify an object code format other than your system's default format.
1036 @xref{Target Selection}, for more information.
1037
1038 @end table
1039
1040 @c man end
1041
1042 @ignore
1043 @c man begin SEEALSO nm
1044 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1045 @c man end
1046 @end ignore
1047
1048 @node objcopy
1049 @chapter objcopy
1050
1051 @c man title objcopy copy and translate object files
1052
1053 @smallexample
1054 @c man begin SYNOPSIS objcopy
1055 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1056 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1057 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1058 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1059 [@option{-S}|@option{--strip-all}]
1060 [@option{-g}|@option{--strip-debug}]
1061 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1062 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1063 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1064 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1065 [@option{--localize-hidden}]
1066 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1067 [@option{--globalize-symbol=}@var{symbolname}]
1068 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1069 [@option{-w}|@option{--wildcard}]
1070 [@option{-x}|@option{--discard-all}]
1071 [@option{-X}|@option{--discard-locals}]
1072 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1073 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1074 [@option{--interleave-width=}@var{width}]
1075 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1076 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1077 [@option{-p}|@option{--preserve-dates}]
1078 [@option{-D}|@option{--enable-deterministic-archives}]
1079 [@option{-U}|@option{--disable-deterministic-archives}]
1080 [@option{--debugging}]
1081 [@option{--gap-fill=}@var{val}]
1082 [@option{--pad-to=}@var{address}]
1083 [@option{--set-start=}@var{val}]
1084 [@option{--adjust-start=}@var{incr}]
1085 [@option{--change-addresses=}@var{incr}]
1086 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1087 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1088 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1089 [@option{--change-warnings}] [@option{--no-change-warnings}]
1090 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1091 [@option{--add-section} @var{sectionname}=@var{filename}]
1092 [@option{--dump-section} @var{sectionname}=@var{filename}]
1093 [@option{--update-section} @var{sectionname}=@var{filename}]
1094 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1095 [@option{--long-section-names} @{enable,disable,keep@}]
1096 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1097 [@option{--reverse-bytes=}@var{num}]
1098 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1099 [@option{--redefine-sym} @var{old}=@var{new}]
1100 [@option{--redefine-syms=}@var{filename}]
1101 [@option{--weaken}]
1102 [@option{--keep-symbols=}@var{filename}]
1103 [@option{--strip-symbols=}@var{filename}]
1104 [@option{--strip-unneeded-symbols=}@var{filename}]
1105 [@option{--keep-global-symbols=}@var{filename}]
1106 [@option{--localize-symbols=}@var{filename}]
1107 [@option{--globalize-symbols=}@var{filename}]
1108 [@option{--weaken-symbols=}@var{filename}]
1109 [@option{--alt-machine-code=}@var{index}]
1110 [@option{--prefix-symbols=}@var{string}]
1111 [@option{--prefix-sections=}@var{string}]
1112 [@option{--prefix-alloc-sections=}@var{string}]
1113 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1114 [@option{--keep-file-symbols}]
1115 [@option{--only-keep-debug}]
1116 [@option{--strip-dwo}]
1117 [@option{--extract-dwo}]
1118 [@option{--extract-symbol}]
1119 [@option{--writable-text}]
1120 [@option{--readonly-text}]
1121 [@option{--pure}]
1122 [@option{--impure}]
1123 [@option{--file-alignment=}@var{num}]
1124 [@option{--heap=}@var{size}]
1125 [@option{--image-base=}@var{address}]
1126 [@option{--section-alignment=}@var{num}]
1127 [@option{--stack=}@var{size}]
1128 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1129 [@option{--compress-debug-sections}]
1130 [@option{--decompress-debug-sections}]
1131 [@option{--dwarf-depth=@var{n}}]
1132 [@option{--dwarf-start=@var{n}}]
1133 [@option{-v}|@option{--verbose}]
1134 [@option{-V}|@option{--version}]
1135 [@option{--help}] [@option{--info}]
1136 @var{infile} [@var{outfile}]
1137 @c man end
1138 @end smallexample
1139
1140 @c man begin DESCRIPTION objcopy
1141 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1142 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1143 read and write the object files. It can write the destination object
1144 file in a format different from that of the source object file. The
1145 exact behavior of @command{objcopy} is controlled by command-line options.
1146 Note that @command{objcopy} should be able to copy a fully linked file
1147 between any two formats. However, copying a relocatable object file
1148 between any two formats may not work as expected.
1149
1150 @command{objcopy} creates temporary files to do its translations and
1151 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1152 translation work; it has access to all the formats described in @sc{bfd}
1153 and thus is able to recognize most formats without being told
1154 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1155
1156 @command{objcopy} can be used to generate S-records by using an output
1157 target of @samp{srec} (e.g., use @samp{-O srec}).
1158
1159 @command{objcopy} can be used to generate a raw binary file by using an
1160 output target of @samp{binary} (e.g., use @option{-O binary}). When
1161 @command{objcopy} generates a raw binary file, it will essentially produce
1162 a memory dump of the contents of the input object file. All symbols and
1163 relocation information will be discarded. The memory dump will start at
1164 the load address of the lowest section copied into the output file.
1165
1166 When generating an S-record or a raw binary file, it may be helpful to
1167 use @option{-S} to remove sections containing debugging information. In
1168 some cases @option{-R} will be useful to remove sections which contain
1169 information that is not needed by the binary file.
1170
1171 Note---@command{objcopy} is not able to change the endianness of its input
1172 files. If the input format has an endianness (some formats do not),
1173 @command{objcopy} can only copy the inputs into file formats that have the
1174 same endianness or which have no endianness (e.g., @samp{srec}).
1175 (However, see the @option{--reverse-bytes} option.)
1176
1177 @c man end
1178
1179 @c man begin OPTIONS objcopy
1180
1181 @table @env
1182 @item @var{infile}
1183 @itemx @var{outfile}
1184 The input and output files, respectively.
1185 If you do not specify @var{outfile}, @command{objcopy} creates a
1186 temporary file and destructively renames the result with
1187 the name of @var{infile}.
1188
1189 @item -I @var{bfdname}
1190 @itemx --input-target=@var{bfdname}
1191 Consider the source file's object format to be @var{bfdname}, rather than
1192 attempting to deduce it. @xref{Target Selection}, for more information.
1193
1194 @item -O @var{bfdname}
1195 @itemx --output-target=@var{bfdname}
1196 Write the output file using the object format @var{bfdname}.
1197 @xref{Target Selection}, for more information.
1198
1199 @item -F @var{bfdname}
1200 @itemx --target=@var{bfdname}
1201 Use @var{bfdname} as the object format for both the input and the output
1202 file; i.e., simply transfer data from source to destination with no
1203 translation. @xref{Target Selection}, for more information.
1204
1205 @item -B @var{bfdarch}
1206 @itemx --binary-architecture=@var{bfdarch}
1207 Useful when transforming a architecture-less input file into an object file.
1208 In this case the output architecture can be set to @var{bfdarch}. This
1209 option will be ignored if the input file has a known @var{bfdarch}. You
1210 can access this binary data inside a program by referencing the special
1211 symbols that are created by the conversion process. These symbols are
1212 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1213 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1214 an object file and then access it in your code using these symbols.
1215
1216 @item -j @var{sectionpattern}
1217 @itemx --only-section=@var{sectionpattern}
1218 Copy only the indicated sections from the input file to the output file.
1219 This option may be given more than once. Note that using this option
1220 inappropriately may make the output file unusable. Wildcard
1221 characters are accepted in @var{sectionpattern}.
1222
1223 @item -R @var{sectionpattern}
1224 @itemx --remove-section=@var{sectionpattern}
1225 Remove any section matching @var{sectionpattern} from the output file.
1226 This option may be given more than once. Note that using this option
1227 inappropriately may make the output file unusable. Wildcard
1228 characters are accepted in @var{sectionpattern}. Using both the
1229 @option{-j} and @option{-R} options together results in undefined
1230 behaviour.
1231
1232 @item -S
1233 @itemx --strip-all
1234 Do not copy relocation and symbol information from the source file.
1235
1236 @item -g
1237 @itemx --strip-debug
1238 Do not copy debugging symbols or sections from the source file.
1239
1240 @item --strip-unneeded
1241 Strip all symbols that are not needed for relocation processing.
1242
1243 @item -K @var{symbolname}
1244 @itemx --keep-symbol=@var{symbolname}
1245 When stripping symbols, keep symbol @var{symbolname} even if it would
1246 normally be stripped. This option may be given more than once.
1247
1248 @item -N @var{symbolname}
1249 @itemx --strip-symbol=@var{symbolname}
1250 Do not copy symbol @var{symbolname} from the source file. This option
1251 may be given more than once.
1252
1253 @item --strip-unneeded-symbol=@var{symbolname}
1254 Do not copy symbol @var{symbolname} from the source file unless it is needed
1255 by a relocation. This option may be given more than once.
1256
1257 @item -G @var{symbolname}
1258 @itemx --keep-global-symbol=@var{symbolname}
1259 Keep only symbol @var{symbolname} global. Make all other symbols local
1260 to the file, so that they are not visible externally. This option may
1261 be given more than once.
1262
1263 @item --localize-hidden
1264 In an ELF object, mark all symbols that have hidden or internal visibility
1265 as local. This option applies on top of symbol-specific localization options
1266 such as @option{-L}.
1267
1268 @item -L @var{symbolname}
1269 @itemx --localize-symbol=@var{symbolname}
1270 Make symbol @var{symbolname} local to the file, so that it is not
1271 visible externally. This option may be given more than once.
1272
1273 @item -W @var{symbolname}
1274 @itemx --weaken-symbol=@var{symbolname}
1275 Make symbol @var{symbolname} weak. This option may be given more than once.
1276
1277 @item --globalize-symbol=@var{symbolname}
1278 Give symbol @var{symbolname} global scoping so that it is visible
1279 outside of the file in which it is defined. This option may be given
1280 more than once.
1281
1282 @item -w
1283 @itemx --wildcard
1284 Permit regular expressions in @var{symbolname}s used in other command
1285 line options. The question mark (?), asterisk (*), backslash (\) and
1286 square brackets ([]) operators can be used anywhere in the symbol
1287 name. If the first character of the symbol name is the exclamation
1288 point (!) then the sense of the switch is reversed for that symbol.
1289 For example:
1290
1291 @smallexample
1292 -w -W !foo -W fo*
1293 @end smallexample
1294
1295 would cause objcopy to weaken all symbols that start with ``fo''
1296 except for the symbol ``foo''.
1297
1298 @item -x
1299 @itemx --discard-all
1300 Do not copy non-global symbols from the source file.
1301 @c FIXME any reason to prefer "non-global" to "local" here?
1302
1303 @item -X
1304 @itemx --discard-locals
1305 Do not copy compiler-generated local symbols.
1306 (These usually start with @samp{L} or @samp{.}.)
1307
1308 @item -b @var{byte}
1309 @itemx --byte=@var{byte}
1310 If interleaving has been enabled via the @option{--interleave} option
1311 then start the range of bytes to keep at the @var{byte}th byte.
1312 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1313 @var{breadth} is the value given by the @option{--interleave} option.
1314
1315 @item -i [@var{breadth}]
1316 @itemx --interleave[=@var{breadth}]
1317 Only copy a range out of every @var{breadth} bytes. (Header data is
1318 not affected). Select which byte in the range begins the copy with
1319 the @option{--byte} option. Select the width of the range with the
1320 @option{--interleave-width} option.
1321
1322 This option is useful for creating files to program @sc{rom}. It is
1323 typically used with an @code{srec} output target. Note that
1324 @command{objcopy} will complain if you do not specify the
1325 @option{--byte} option as well.
1326
1327 The default interleave breadth is 4, so with @option{--byte} set to 0,
1328 @command{objcopy} would copy the first byte out of every four bytes
1329 from the input to the output.
1330
1331 @item --interleave-width=@var{width}
1332 When used with the @option{--interleave} option, copy @var{width}
1333 bytes at a time. The start of the range of bytes to be copied is set
1334 by the @option{--byte} option, and the extent of the range is set with
1335 the @option{--interleave} option.
1336
1337 The default value for this option is 1. The value of @var{width} plus
1338 the @var{byte} value set by the @option{--byte} option must not exceed
1339 the interleave breadth set by the @option{--interleave} option.
1340
1341 This option can be used to create images for two 16-bit flashes interleaved
1342 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1343 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1344 commands. If the input was '12345678' then the outputs would be
1345 '1256' and '3478' respectively.
1346
1347 @item -p
1348 @itemx --preserve-dates
1349 Set the access and modification dates of the output file to be the same
1350 as those of the input file.
1351
1352 @item -D
1353 @itemx --enable-deterministic-archives
1354 @cindex deterministic archives
1355 @kindex --enable-deterministic-archives
1356 Operate in @emph{deterministic} mode. When copying archive members
1357 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1358 and use consistent file modes for all files.
1359
1360 If @file{binutils} was configured with
1361 @option{--enable-deterministic-archives}, then this mode is on by default.
1362 It can be disabled with the @samp{-U} option, below.
1363
1364 @item -U
1365 @itemx --disable-deterministic-archives
1366 @cindex deterministic archives
1367 @kindex --enable-deterministic-archives
1368 Do @emph{not} operate in @emph{deterministic} mode. This is the
1369 inverse of the @option{-D} option, above: when copying archive members
1370 and writing the archive index, use their actual UID, GID, timestamp,
1371 and file mode values.
1372
1373 This is the default unless @file{binutils} was configured with
1374 @option{--enable-deterministic-archives}.
1375
1376 @item --debugging
1377 Convert debugging information, if possible. This is not the default
1378 because only certain debugging formats are supported, and the
1379 conversion process can be time consuming.
1380
1381 @item --gap-fill @var{val}
1382 Fill gaps between sections with @var{val}. This operation applies to
1383 the @emph{load address} (LMA) of the sections. It is done by increasing
1384 the size of the section with the lower address, and filling in the extra
1385 space created with @var{val}.
1386
1387 @item --pad-to @var{address}
1388 Pad the output file up to the load address @var{address}. This is
1389 done by increasing the size of the last section. The extra space is
1390 filled in with the value specified by @option{--gap-fill} (default zero).
1391
1392 @item --set-start @var{val}
1393 Set the start address of the new file to @var{val}. Not all object file
1394 formats support setting the start address.
1395
1396 @item --change-start @var{incr}
1397 @itemx --adjust-start @var{incr}
1398 @cindex changing start address
1399 Change the start address by adding @var{incr}. Not all object file
1400 formats support setting the start address.
1401
1402 @item --change-addresses @var{incr}
1403 @itemx --adjust-vma @var{incr}
1404 @cindex changing object addresses
1405 Change the VMA and LMA addresses of all sections, as well as the start
1406 address, by adding @var{incr}. Some object file formats do not permit
1407 section addresses to be changed arbitrarily. Note that this does not
1408 relocate the sections; if the program expects sections to be loaded at a
1409 certain address, and this option is used to change the sections such
1410 that they are loaded at a different address, the program may fail.
1411
1412 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1413 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1414 @cindex changing section address
1415 Set or change both the VMA address and the LMA address of any section
1416 matching @var{sectionpattern}. If @samp{=} is used, the section
1417 address is set to @var{val}. Otherwise, @var{val} is added to or
1418 subtracted from the section address. See the comments under
1419 @option{--change-addresses}, above. If @var{sectionpattern} does not
1420 match any sections in the input file, a warning will be issued, unless
1421 @option{--no-change-warnings} is used.
1422
1423 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1424 @cindex changing section LMA
1425 Set or change the LMA address of any sections matching
1426 @var{sectionpattern}. The LMA address is the address where the
1427 section will be loaded into memory at program load time. Normally
1428 this is the same as the VMA address, which is the address of the
1429 section at program run time, but on some systems, especially those
1430 where a program is held in ROM, the two can be different. If @samp{=}
1431 is used, the section address is set to @var{val}. Otherwise,
1432 @var{val} is added to or subtracted from the section address. See the
1433 comments under @option{--change-addresses}, above. If
1434 @var{sectionpattern} does not match any sections in the input file, a
1435 warning will be issued, unless @option{--no-change-warnings} is used.
1436
1437 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1438 @cindex changing section VMA
1439 Set or change the VMA address of any section matching
1440 @var{sectionpattern}. The VMA address is the address where the
1441 section will be located once the program has started executing.
1442 Normally this is the same as the LMA address, which is the address
1443 where the section will be loaded into memory, but on some systems,
1444 especially those where a program is held in ROM, the two can be
1445 different. If @samp{=} is used, the section address is set to
1446 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1447 section address. See the comments under @option{--change-addresses},
1448 above. If @var{sectionpattern} does not match any sections in the
1449 input file, a warning will be issued, unless
1450 @option{--no-change-warnings} is used.
1451
1452 @item --change-warnings
1453 @itemx --adjust-warnings
1454 If @option{--change-section-address} or @option{--change-section-lma} or
1455 @option{--change-section-vma} is used, and the section pattern does not
1456 match any sections, issue a warning. This is the default.
1457
1458 @item --no-change-warnings
1459 @itemx --no-adjust-warnings
1460 Do not issue a warning if @option{--change-section-address} or
1461 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1462 if the section pattern does not match any sections.
1463
1464 @item --set-section-flags @var{sectionpattern}=@var{flags}
1465 Set the flags for any sections matching @var{sectionpattern}. The
1466 @var{flags} argument is a comma separated string of flag names. The
1467 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1468 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1469 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1470 for a section which does not have contents, but it is not meaningful
1471 to clear the @samp{contents} flag of a section which does have
1472 contents--just remove the section instead. Not all flags are
1473 meaningful for all object file formats.
1474
1475 @item --add-section @var{sectionname}=@var{filename}
1476 Add a new section named @var{sectionname} while copying the file. The
1477 contents of the new section are taken from the file @var{filename}. The
1478 size of the section will be the size of the file. This option only
1479 works on file formats which can support sections with arbitrary names.
1480 Note - it may be necessary to use the @option{--set-section-flags}
1481 option to set the attributes of the newly created section.
1482
1483 @item --dump-section @var{sectionname}=@var{filename}
1484 Place the contents of section named @var{sectionname} into the file
1485 @var{filename}, overwriting any contents that may have been there
1486 previously. This option is the inverse of @option{--add-section}.
1487 This option is similar to the @option{--only-section} option except
1488 that it does not create a formatted file, it just dumps the contents
1489 as raw binary data, without applying any relocations. The option can
1490 be specified more than once.
1491
1492 @item --update-section @var{sectionname}=@var{filename}
1493 Replace the existing contents of a section named @var{sectionname}
1494 with the contents of file @var{filename}. The size of the section
1495 will be adjusted to the size of the file. The section flags for
1496 @var{sectionname} will be unchanged. For ELF format files the section
1497 to segment mapping will also remain unchanged, something which is not
1498 possible using @option{--remove-section} followed by
1499 @option{--add-section}. The option can be specified more than once.
1500
1501 Note - it is possible to use @option{--rename-section} and
1502 @option{--update-section} to both update and rename a section from one
1503 command line. In this case, pass the original section name to
1504 @option{--update-section}, and the original and new section names to
1505 @option{--rename-section}.
1506
1507 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1508 Rename a section from @var{oldname} to @var{newname}, optionally
1509 changing the section's flags to @var{flags} in the process. This has
1510 the advantage over usng a linker script to perform the rename in that
1511 the output stays as an object file and does not become a linked
1512 executable.
1513
1514 This option is particularly helpful when the input format is binary,
1515 since this will always create a section called .data. If for example,
1516 you wanted instead to create a section called .rodata containing binary
1517 data you could use the following command line to achieve it:
1518
1519 @smallexample
1520 objcopy -I binary -O <output_format> -B <architecture> \
1521 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1522 <input_binary_file> <output_object_file>
1523 @end smallexample
1524
1525 @item --long-section-names @{enable,disable,keep@}
1526 Controls the handling of long section names when processing @code{COFF}
1527 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1528 is to preserve long section names if any are present in the input file.
1529 The @samp{enable} and @samp{disable} options forcibly enable or disable
1530 the use of long section names in the output object; when @samp{disable}
1531 is in effect, any long section names in the input object will be truncated.
1532 The @samp{enable} option will only emit long section names if any are
1533 present in the inputs; this is mostly the same as @samp{keep}, but it
1534 is left undefined whether the @samp{enable} option might force the
1535 creation of an empty string table in the output file.
1536
1537 @item --change-leading-char
1538 Some object file formats use special characters at the start of
1539 symbols. The most common such character is underscore, which compilers
1540 often add before every symbol. This option tells @command{objcopy} to
1541 change the leading character of every symbol when it converts between
1542 object file formats. If the object file formats use the same leading
1543 character, this option has no effect. Otherwise, it will add a
1544 character, or remove a character, or change a character, as
1545 appropriate.
1546
1547 @item --remove-leading-char
1548 If the first character of a global symbol is a special symbol leading
1549 character used by the object file format, remove the character. The
1550 most common symbol leading character is underscore. This option will
1551 remove a leading underscore from all global symbols. This can be useful
1552 if you want to link together objects of different file formats with
1553 different conventions for symbol names. This is different from
1554 @option{--change-leading-char} because it always changes the symbol name
1555 when appropriate, regardless of the object file format of the output
1556 file.
1557
1558 @item --reverse-bytes=@var{num}
1559 Reverse the bytes in a section with output contents. A section length must
1560 be evenly divisible by the value given in order for the swap to be able to
1561 take place. Reversing takes place before the interleaving is performed.
1562
1563 This option is used typically in generating ROM images for problematic
1564 target systems. For example, on some target boards, the 32-bit words
1565 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1566 regardless of the CPU byte order. Depending on the programming model, the
1567 endianness of the ROM may need to be modified.
1568
1569 Consider a simple file with a section containing the following eight
1570 bytes: @code{12345678}.
1571
1572 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1573 output file would be ordered @code{21436587}.
1574
1575 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1576 output file would be ordered @code{43218765}.
1577
1578 By using @samp{--reverse-bytes=2} for the above example, followed by
1579 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1580 output file would be ordered @code{34127856}.
1581
1582 @item --srec-len=@var{ival}
1583 Meaningful only for srec output. Set the maximum length of the Srecords
1584 being produced to @var{ival}. This length covers both address, data and
1585 crc fields.
1586
1587 @item --srec-forceS3
1588 Meaningful only for srec output. Avoid generation of S1/S2 records,
1589 creating S3-only record format.
1590
1591 @item --redefine-sym @var{old}=@var{new}
1592 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1593 when one is trying link two things together for which you have no
1594 source, and there are name collisions.
1595
1596 @item --redefine-syms=@var{filename}
1597 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1598 listed in the file @var{filename}. @var{filename} is simply a flat file,
1599 with one symbol pair per line. Line comments may be introduced by the hash
1600 character. This option may be given more than once.
1601
1602 @item --weaken
1603 Change all global symbols in the file to be weak. This can be useful
1604 when building an object which will be linked against other objects using
1605 the @option{-R} option to the linker. This option is only effective when
1606 using an object file format which supports weak symbols.
1607
1608 @item --keep-symbols=@var{filename}
1609 Apply @option{--keep-symbol} option to each symbol listed in the file
1610 @var{filename}. @var{filename} is simply a flat file, with one symbol
1611 name per line. Line comments may be introduced by the hash character.
1612 This option may be given more than once.
1613
1614 @item --strip-symbols=@var{filename}
1615 Apply @option{--strip-symbol} option to each symbol listed in the file
1616 @var{filename}. @var{filename} is simply a flat file, with one symbol
1617 name per line. Line comments may be introduced by the hash character.
1618 This option may be given more than once.
1619
1620 @item --strip-unneeded-symbols=@var{filename}
1621 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1622 the file @var{filename}. @var{filename} is simply a flat file, with one
1623 symbol name per line. Line comments may be introduced by the hash
1624 character. This option may be given more than once.
1625
1626 @item --keep-global-symbols=@var{filename}
1627 Apply @option{--keep-global-symbol} option to each symbol listed in the
1628 file @var{filename}. @var{filename} is simply a flat file, with one
1629 symbol name per line. Line comments may be introduced by the hash
1630 character. This option may be given more than once.
1631
1632 @item --localize-symbols=@var{filename}
1633 Apply @option{--localize-symbol} option to each symbol listed in the file
1634 @var{filename}. @var{filename} is simply a flat file, with one symbol
1635 name per line. Line comments may be introduced by the hash character.
1636 This option may be given more than once.
1637
1638 @item --globalize-symbols=@var{filename}
1639 Apply @option{--globalize-symbol} option to each symbol listed in the file
1640 @var{filename}. @var{filename} is simply a flat file, with one symbol
1641 name per line. Line comments may be introduced by the hash character.
1642 This option may be given more than once.
1643
1644 @item --weaken-symbols=@var{filename}
1645 Apply @option{--weaken-symbol} option to each symbol listed in the file
1646 @var{filename}. @var{filename} is simply a flat file, with one symbol
1647 name per line. Line comments may be introduced by the hash character.
1648 This option may be given more than once.
1649
1650 @item --alt-machine-code=@var{index}
1651 If the output architecture has alternate machine codes, use the
1652 @var{index}th code instead of the default one. This is useful in case
1653 a machine is assigned an official code and the tool-chain adopts the
1654 new code, but other applications still depend on the original code
1655 being used. For ELF based architectures if the @var{index}
1656 alternative does not exist then the value is treated as an absolute
1657 number to be stored in the e_machine field of the ELF header.
1658
1659 @item --writable-text
1660 Mark the output text as writable. This option isn't meaningful for all
1661 object file formats.
1662
1663 @item --readonly-text
1664 Make the output text write protected. This option isn't meaningful for all
1665 object file formats.
1666
1667 @item --pure
1668 Mark the output file as demand paged. This option isn't meaningful for all
1669 object file formats.
1670
1671 @item --impure
1672 Mark the output file as impure. This option isn't meaningful for all
1673 object file formats.
1674
1675 @item --prefix-symbols=@var{string}
1676 Prefix all symbols in the output file with @var{string}.
1677
1678 @item --prefix-sections=@var{string}
1679 Prefix all section names in the output file with @var{string}.
1680
1681 @item --prefix-alloc-sections=@var{string}
1682 Prefix all the names of all allocated sections in the output file with
1683 @var{string}.
1684
1685 @item --add-gnu-debuglink=@var{path-to-file}
1686 Creates a .gnu_debuglink section which contains a reference to
1687 @var{path-to-file} and adds it to the output file. Note: the file at
1688 @var{path-to-file} must exist. Part of the process of adding the
1689 .gnu_debuglink section involves embedding a checksum of the contents
1690 of the debug info file into the section.
1691
1692 If the debug info file is built in one location but it is going to be
1693 installed at a later time into a different location then do not use
1694 the path to the installed location. The @option{--add-gnu-debuglink}
1695 option will fail because the installed file does not exist yet.
1696 Instead put the debug info file in the current directory and use the
1697 @option{--add-gnu-debuglink} option without any directory components,
1698 like this:
1699
1700 @smallexample
1701 objcopy --add-gnu-debuglink=foo.debug
1702 @end smallexample
1703
1704 At debug time the debugger will attempt to look for the separate debug
1705 info file in a set of known locations. The exact set of these
1706 locations varies depending upon the distribution being used, but it
1707 typically includes:
1708
1709 @table @code
1710
1711 @item * The same directory as the executable.
1712
1713 @item * A sub-directory of the directory containing the executable
1714 called .debug
1715
1716 @item * A global debug directory such as /usr/lib/debug.
1717 @end table
1718
1719 As long as the debug info file has been installed into one of these
1720 locations before the debugger is run everything should work
1721 correctly.
1722
1723 @item --keep-file-symbols
1724 When stripping a file, perhaps with @option{--strip-debug} or
1725 @option{--strip-unneeded}, retain any symbols specifying source file names,
1726 which would otherwise get stripped.
1727
1728 @item --only-keep-debug
1729 Strip a file, removing contents of any sections that would not be
1730 stripped by @option{--strip-debug} and leaving the debugging sections
1731 intact. In ELF files, this preserves all note sections in the output.
1732
1733 Note - the section headers of the stripped sections are preserved,
1734 including their sizes, but the contents of the section are discarded.
1735 The section headers are preserved so that other tools can match up the
1736 debuginfo file with the real executable, even if that executable has
1737 been relocated to a different address space.
1738
1739 The intention is that this option will be used in conjunction with
1740 @option{--add-gnu-debuglink} to create a two part executable. One a
1741 stripped binary which will occupy less space in RAM and in a
1742 distribution and the second a debugging information file which is only
1743 needed if debugging abilities are required. The suggested procedure
1744 to create these files is as follows:
1745
1746 @enumerate
1747 @item Link the executable as normal. Assuming that is is called
1748 @code{foo} then...
1749 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1750 create a file containing the debugging info.
1751 @item Run @code{objcopy --strip-debug foo} to create a
1752 stripped executable.
1753 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1754 to add a link to the debugging info into the stripped executable.
1755 @end enumerate
1756
1757 Note---the choice of @code{.dbg} as an extension for the debug info
1758 file is arbitrary. Also the @code{--only-keep-debug} step is
1759 optional. You could instead do this:
1760
1761 @enumerate
1762 @item Link the executable as normal.
1763 @item Copy @code{foo} to @code{foo.full}
1764 @item Run @code{objcopy --strip-debug foo}
1765 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1766 @end enumerate
1767
1768 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1769 full executable. It does not have to be a file created by the
1770 @option{--only-keep-debug} switch.
1771
1772 Note---this switch is only intended for use on fully linked files. It
1773 does not make sense to use it on object files where the debugging
1774 information may be incomplete. Besides the gnu_debuglink feature
1775 currently only supports the presence of one filename containing
1776 debugging information, not multiple filenames on a one-per-object-file
1777 basis.
1778
1779 @item --strip-dwo
1780 Remove the contents of all DWARF .dwo sections, leaving the
1781 remaining debugging sections and all symbols intact.
1782 This option is intended for use by the compiler as part of
1783 the @option{-gsplit-dwarf} option, which splits debug information
1784 between the .o file and a separate .dwo file. The compiler
1785 generates all debug information in the same file, then uses
1786 the @option{--extract-dwo} option to copy the .dwo sections to
1787 the .dwo file, then the @option{--strip-dwo} option to remove
1788 those sections from the original .o file.
1789
1790 @item --extract-dwo
1791 Extract the contents of all DWARF .dwo sections. See the
1792 @option{--strip-dwo} option for more information.
1793
1794 @item --file-alignment @var{num}
1795 Specify the file alignment. Sections in the file will always begin at
1796 file offsets which are multiples of this number. This defaults to
1797 512.
1798 [This option is specific to PE targets.]
1799
1800 @item --heap @var{reserve}
1801 @itemx --heap @var{reserve},@var{commit}
1802 Specify the number of bytes of memory to reserve (and optionally commit)
1803 to be used as heap for this program.
1804 [This option is specific to PE targets.]
1805
1806 @item --image-base @var{value}
1807 Use @var{value} as the base address of your program or dll. This is
1808 the lowest memory location that will be used when your program or dll
1809 is loaded. To reduce the need to relocate and improve performance of
1810 your dlls, each should have a unique base address and not overlap any
1811 other dlls. The default is 0x400000 for executables, and 0x10000000
1812 for dlls.
1813 [This option is specific to PE targets.]
1814
1815 @item --section-alignment @var{num}
1816 Sets the section alignment. Sections in memory will always begin at
1817 addresses which are a multiple of this number. Defaults to 0x1000.
1818 [This option is specific to PE targets.]
1819
1820 @item --stack @var{reserve}
1821 @itemx --stack @var{reserve},@var{commit}
1822 Specify the number of bytes of memory to reserve (and optionally commit)
1823 to be used as stack for this program.
1824 [This option is specific to PE targets.]
1825
1826 @item --subsystem @var{which}
1827 @itemx --subsystem @var{which}:@var{major}
1828 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1829 Specifies the subsystem under which your program will execute. The
1830 legal values for @var{which} are @code{native}, @code{windows},
1831 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1832 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1833 the subsystem version also. Numeric values are also accepted for
1834 @var{which}.
1835 [This option is specific to PE targets.]
1836
1837 @item --extract-symbol
1838 Keep the file's section flags and symbols but remove all section data.
1839 Specifically, the option:
1840
1841 @itemize
1842 @item removes the contents of all sections;
1843 @item sets the size of every section to zero; and
1844 @item sets the file's start address to zero.
1845 @end itemize
1846
1847 This option is used to build a @file{.sym} file for a VxWorks kernel.
1848 It can also be a useful way of reducing the size of a @option{--just-symbols}
1849 linker input file.
1850
1851 @item --compress-debug-sections
1852 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
1853 ELF ABI. Note - if compression would actually make a section
1854 @emph{larger}, then it is not compressed.
1855
1856 @item --compress-debug-sections=none
1857 @itemx --compress-debug-sections=zlib
1858 @itemx --compress-debug-sections=zlib-gnu
1859 @itemx --compress-debug-sections=zlib-gabi
1860 For ELF files, these options control how DWARF debug sections are
1861 compressed. @option{--compress-debug-sections=none} is equivalent
1862 to @option{--nocompress-debug-sections}.
1863 @option{--compress-debug-sections=zlib} and
1864 @option{--compress-debug-sections=zlib-gabi} are equivalent to
1865 @option{--compress-debug-sections}.
1866 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
1867 sections using zlib. The debug sections are renamed to begin with
1868 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
1869 actually make a section @emph{larger}, then it is not compressed nor
1870 renamed.
1871
1872 @item --decompress-debug-sections
1873 Decompress DWARF debug sections using zlib. The original section
1874 names of the compressed sections are restored.
1875
1876 @item -V
1877 @itemx --version
1878 Show the version number of @command{objcopy}.
1879
1880 @item -v
1881 @itemx --verbose
1882 Verbose output: list all object files modified. In the case of
1883 archives, @samp{objcopy -V} lists all members of the archive.
1884
1885 @item --help
1886 Show a summary of the options to @command{objcopy}.
1887
1888 @item --info
1889 Display a list showing all architectures and object formats available.
1890 @end table
1891
1892 @c man end
1893
1894 @ignore
1895 @c man begin SEEALSO objcopy
1896 ld(1), objdump(1), and the Info entries for @file{binutils}.
1897 @c man end
1898 @end ignore
1899
1900 @node objdump
1901 @chapter objdump
1902
1903 @cindex object file information
1904 @kindex objdump
1905
1906 @c man title objdump display information from object files.
1907
1908 @smallexample
1909 @c man begin SYNOPSIS objdump
1910 objdump [@option{-a}|@option{--archive-headers}]
1911 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1912 [@option{-C}|@option{--demangle}[=@var{style}] ]
1913 [@option{-d}|@option{--disassemble}]
1914 [@option{-D}|@option{--disassemble-all}]
1915 [@option{-z}|@option{--disassemble-zeroes}]
1916 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1917 [@option{-f}|@option{--file-headers}]
1918 [@option{-F}|@option{--file-offsets}]
1919 [@option{--file-start-context}]
1920 [@option{-g}|@option{--debugging}]
1921 [@option{-e}|@option{--debugging-tags}]
1922 [@option{-h}|@option{--section-headers}|@option{--headers}]
1923 [@option{-i}|@option{--info}]
1924 [@option{-j} @var{section}|@option{--section=}@var{section}]
1925 [@option{-l}|@option{--line-numbers}]
1926 [@option{-S}|@option{--source}]
1927 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1928 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1929 [@option{-p}|@option{--private-headers}]
1930 [@option{-P} @var{options}|@option{--private=}@var{options}]
1931 [@option{-r}|@option{--reloc}]
1932 [@option{-R}|@option{--dynamic-reloc}]
1933 [@option{-s}|@option{--full-contents}]
1934 [@option{-W[lLiaprmfFsoRt]}|
1935 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames]
1936 [=aranges,=macro,=frames,=frames-interp,=str,=loc]
1937 [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
1938 [=trace_aranges,=gdb_index]
1939 [@option{-G}|@option{--stabs}]
1940 [@option{-t}|@option{--syms}]
1941 [@option{-T}|@option{--dynamic-syms}]
1942 [@option{-x}|@option{--all-headers}]
1943 [@option{-w}|@option{--wide}]
1944 [@option{--start-address=}@var{address}]
1945 [@option{--stop-address=}@var{address}]
1946 [@option{--prefix-addresses}]
1947 [@option{--[no-]show-raw-insn}]
1948 [@option{--adjust-vma=}@var{offset}]
1949 [@option{--special-syms}]
1950 [@option{--prefix=}@var{prefix}]
1951 [@option{--prefix-strip=}@var{level}]
1952 [@option{--insn-width=}@var{width}]
1953 [@option{-V}|@option{--version}]
1954 [@option{-H}|@option{--help}]
1955 @var{objfile}@dots{}
1956 @c man end
1957 @end smallexample
1958
1959 @c man begin DESCRIPTION objdump
1960
1961 @command{objdump} displays information about one or more object files.
1962 The options control what particular information to display. This
1963 information is mostly useful to programmers who are working on the
1964 compilation tools, as opposed to programmers who just want their
1965 program to compile and work.
1966
1967 @var{objfile}@dots{} are the object files to be examined. When you
1968 specify archives, @command{objdump} shows information on each of the member
1969 object files.
1970
1971 @c man end
1972
1973 @c man begin OPTIONS objdump
1974
1975 The long and short forms of options, shown here as alternatives, are
1976 equivalent. At least one option from the list
1977 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1978
1979 @table @env
1980 @item -a
1981 @itemx --archive-header
1982 @cindex archive headers
1983 If any of the @var{objfile} files are archives, display the archive
1984 header information (in a format similar to @samp{ls -l}). Besides the
1985 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1986 the object file format of each archive member.
1987
1988 @item --adjust-vma=@var{offset}
1989 @cindex section addresses in objdump
1990 @cindex VMA in objdump
1991 When dumping information, first add @var{offset} to all the section
1992 addresses. This is useful if the section addresses do not correspond to
1993 the symbol table, which can happen when putting sections at particular
1994 addresses when using a format which can not represent section addresses,
1995 such as a.out.
1996
1997 @item -b @var{bfdname}
1998 @itemx --target=@var{bfdname}
1999 @cindex object code format
2000 Specify that the object-code format for the object files is
2001 @var{bfdname}. This option may not be necessary; @var{objdump} can
2002 automatically recognize many formats.
2003
2004 For example,
2005 @example
2006 objdump -b oasys -m vax -h fu.o
2007 @end example
2008 @noindent
2009 displays summary information from the section headers (@option{-h}) of
2010 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2011 file in the format produced by Oasys compilers. You can list the
2012 formats available with the @option{-i} option.
2013 @xref{Target Selection}, for more information.
2014
2015 @item -C
2016 @itemx --demangle[=@var{style}]
2017 @cindex demangling in objdump
2018 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2019 Besides removing any initial underscore prepended by the system, this
2020 makes C++ function names readable. Different compilers have different
2021 mangling styles. The optional demangling style argument can be used to
2022 choose an appropriate demangling style for your compiler. @xref{c++filt},
2023 for more information on demangling.
2024
2025 @item -g
2026 @itemx --debugging
2027 Display debugging information. This attempts to parse STABS and IEEE
2028 debugging format information stored in the file and print it out using
2029 a C like syntax. If neither of these formats are found this option
2030 falls back on the @option{-W} option to print any DWARF information in
2031 the file.
2032
2033 @item -e
2034 @itemx --debugging-tags
2035 Like @option{-g}, but the information is generated in a format compatible
2036 with ctags tool.
2037
2038 @item -d
2039 @itemx --disassemble
2040 @cindex disassembling object code
2041 @cindex machine instructions
2042 Display the assembler mnemonics for the machine instructions from
2043 @var{objfile}. This option only disassembles those sections which are
2044 expected to contain instructions.
2045
2046 @item -D
2047 @itemx --disassemble-all
2048 Like @option{-d}, but disassemble the contents of all sections, not just
2049 those expected to contain instructions.
2050
2051 This option also has a subtle effect on the disassembly of
2052 instructions in code sections. When option @option{-d} is in effect
2053 objdump will assume that any symbols present in a code section occur
2054 on the boundary between instructions and it will refuse to disassemble
2055 across such a boundary. When option @option{-D} is in effect however
2056 this assumption is supressed. This means that it is possible for the
2057 output of @option{-d} and @option{-D} to differ if, for example, data
2058 is stored in code sections.
2059
2060 If the target is an ARM architecture this switch also has the effect
2061 of forcing the disassembler to decode pieces of data found in code
2062 sections as if they were instructions.
2063
2064 @item --prefix-addresses
2065 When disassembling, print the complete address on each line. This is
2066 the older disassembly format.
2067
2068 @item -EB
2069 @itemx -EL
2070 @itemx --endian=@{big|little@}
2071 @cindex endianness
2072 @cindex disassembly endianness
2073 Specify the endianness of the object files. This only affects
2074 disassembly. This can be useful when disassembling a file format which
2075 does not describe endianness information, such as S-records.
2076
2077 @item -f
2078 @itemx --file-headers
2079 @cindex object file header
2080 Display summary information from the overall header of
2081 each of the @var{objfile} files.
2082
2083 @item -F
2084 @itemx --file-offsets
2085 @cindex object file offsets
2086 When disassembling sections, whenever a symbol is displayed, also
2087 display the file offset of the region of data that is about to be
2088 dumped. If zeroes are being skipped, then when disassembly resumes,
2089 tell the user how many zeroes were skipped and the file offset of the
2090 location from where the disassembly resumes. When dumping sections,
2091 display the file offset of the location from where the dump starts.
2092
2093 @item --file-start-context
2094 @cindex source code context
2095 Specify that when displaying interlisted source code/disassembly
2096 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2097 context to the start of the file.
2098
2099 @item -h
2100 @itemx --section-headers
2101 @itemx --headers
2102 @cindex section headers
2103 Display summary information from the section headers of the
2104 object file.
2105
2106 File segments may be relocated to nonstandard addresses, for example by
2107 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2108 @command{ld}. However, some object file formats, such as a.out, do not
2109 store the starting address of the file segments. In those situations,
2110 although @command{ld} relocates the sections correctly, using @samp{objdump
2111 -h} to list the file section headers cannot show the correct addresses.
2112 Instead, it shows the usual addresses, which are implicit for the
2113 target.
2114
2115 @item -H
2116 @itemx --help
2117 Print a summary of the options to @command{objdump} and exit.
2118
2119 @item -i
2120 @itemx --info
2121 @cindex architectures available
2122 @cindex object formats available
2123 Display a list showing all architectures and object formats available
2124 for specification with @option{-b} or @option{-m}.
2125
2126 @item -j @var{name}
2127 @itemx --section=@var{name}
2128 @cindex section information
2129 Display information only for section @var{name}.
2130
2131 @item -l
2132 @itemx --line-numbers
2133 @cindex source filenames for object files
2134 Label the display (using debugging information) with the filename and
2135 source line numbers corresponding to the object code or relocs shown.
2136 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2137
2138 @item -m @var{machine}
2139 @itemx --architecture=@var{machine}
2140 @cindex architecture
2141 @cindex disassembly architecture
2142 Specify the architecture to use when disassembling object files. This
2143 can be useful when disassembling object files which do not describe
2144 architecture information, such as S-records. You can list the available
2145 architectures with the @option{-i} option.
2146
2147 If the target is an ARM architecture then this switch has an
2148 additional effect. It restricts the disassembly to only those
2149 instructions supported by the architecture specified by @var{machine}.
2150 If it is necessary to use this switch because the input file does not
2151 contain any architecture information, but it is also desired to
2152 disassemble all the instructions use @option{-marm}.
2153
2154 @item -M @var{options}
2155 @itemx --disassembler-options=@var{options}
2156 Pass target specific information to the disassembler. Only supported on
2157 some targets. If it is necessary to specify more than one
2158 disassembler option then multiple @option{-M} options can be used or
2159 can be placed together into a comma separated list.
2160
2161 If the target is an ARM architecture then this switch can be used to
2162 select which register name set is used during disassembler. Specifying
2163 @option{-M reg-names-std} (the default) will select the register names as
2164 used in ARM's instruction set documentation, but with register 13 called
2165 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2166 @option{-M reg-names-apcs} will select the name set used by the ARM
2167 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2168 just use @samp{r} followed by the register number.
2169
2170 There are also two variants on the APCS register naming scheme enabled
2171 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2172 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2173 with the normal register names or the special register names).
2174
2175 This option can also be used for ARM architectures to force the
2176 disassembler to interpret all instructions as Thumb instructions by
2177 using the switch @option{--disassembler-options=force-thumb}. This can be
2178 useful when attempting to disassemble thumb code produced by other
2179 compilers.
2180
2181 For the x86, some of the options duplicate functions of the @option{-m}
2182 switch, but allow finer grained control. Multiple selections from the
2183 following may be specified as a comma separated string.
2184 @table @code
2185 @item x86-64
2186 @itemx i386
2187 @itemx i8086
2188 Select disassembly for the given architecture.
2189
2190 @item intel
2191 @itemx att
2192 Select between intel syntax mode and AT&T syntax mode.
2193
2194 @item amd64
2195 @itemx intel64
2196 Select between AMD64 ISA and Intel64 ISA.
2197
2198 @item intel-mnemonic
2199 @itemx att-mnemonic
2200 Select between intel mnemonic mode and AT&T mnemonic mode.
2201 Note: @code{intel-mnemonic} implies @code{intel} and
2202 @code{att-mnemonic} implies @code{att}.
2203
2204 @item addr64
2205 @itemx addr32
2206 @itemx addr16
2207 @itemx data32
2208 @itemx data16
2209 Specify the default address size and operand size. These four options
2210 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2211 appear later in the option string.
2212
2213 @item suffix
2214 When in AT&T mode, instructs the disassembler to print a mnemonic
2215 suffix even when the suffix could be inferred by the operands.
2216 @end table
2217
2218 For PowerPC, @option{booke} controls the disassembly of BookE
2219 instructions. @option{32} and @option{64} select PowerPC and
2220 PowerPC64 disassembly, respectively. @option{e300} selects
2221 disassembly for the e300 family. @option{440} selects disassembly for
2222 the PowerPC 440. @option{ppcps} selects disassembly for the paired
2223 single instructions of the PPC750CL.
2224
2225 For MIPS, this option controls the printing of instruction mnemonic
2226 names and register names in disassembled instructions. Multiple
2227 selections from the following may be specified as a comma separated
2228 string, and invalid options are ignored:
2229
2230 @table @code
2231 @item no-aliases
2232 Print the 'raw' instruction mnemonic instead of some pseudo
2233 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2234 'sll' instead of 'nop', etc.
2235
2236 @item msa
2237 Disassemble MSA instructions.
2238
2239 @item virt
2240 Disassemble the virtualization ASE instructions.
2241
2242 @item xpa
2243 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2244
2245 @item gpr-names=@var{ABI}
2246 Print GPR (general-purpose register) names as appropriate
2247 for the specified ABI. By default, GPR names are selected according to
2248 the ABI of the binary being disassembled.
2249
2250 @item fpr-names=@var{ABI}
2251 Print FPR (floating-point register) names as
2252 appropriate for the specified ABI. By default, FPR numbers are printed
2253 rather than names.
2254
2255 @item cp0-names=@var{ARCH}
2256 Print CP0 (system control coprocessor; coprocessor 0) register names
2257 as appropriate for the CPU or architecture specified by
2258 @var{ARCH}. By default, CP0 register names are selected according to
2259 the architecture and CPU of the binary being disassembled.
2260
2261 @item hwr-names=@var{ARCH}
2262 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2263 as appropriate for the CPU or architecture specified by
2264 @var{ARCH}. By default, HWR names are selected according to
2265 the architecture and CPU of the binary being disassembled.
2266
2267 @item reg-names=@var{ABI}
2268 Print GPR and FPR names as appropriate for the selected ABI.
2269
2270 @item reg-names=@var{ARCH}
2271 Print CPU-specific register names (CP0 register and HWR names)
2272 as appropriate for the selected CPU or architecture.
2273 @end table
2274
2275 For any of the options listed above, @var{ABI} or
2276 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2277 rather than names, for the selected types of registers.
2278 You can list the available values of @var{ABI} and @var{ARCH} using
2279 the @option{--help} option.
2280
2281 For VAX, you can specify function entry addresses with @option{-M
2282 entry:0xf00ba}. You can use this multiple times to properly
2283 disassemble VAX binary files that don't contain symbol tables (like
2284 ROM dumps). In these cases, the function entry mask would otherwise
2285 be decoded as VAX instructions, which would probably lead the rest
2286 of the function being wrongly disassembled.
2287
2288 @item -p
2289 @itemx --private-headers
2290 Print information that is specific to the object file format. The exact
2291 information printed depends upon the object file format. For some
2292 object file formats, no additional information is printed.
2293
2294 @item -P @var{options}
2295 @itemx --private=@var{options}
2296 Print information that is specific to the object file format. The
2297 argument @var{options} is a comma separated list that depends on the
2298 format (the lists of options is displayed with the help).
2299
2300 For XCOFF, the available options are:
2301 @table @code
2302 @item header
2303 @item aout
2304 @item sections
2305 @item syms
2306 @item relocs
2307 @item lineno,
2308 @item loader
2309 @item except
2310 @item typchk
2311 @item traceback
2312 @item toc
2313 @item ldinfo
2314 @end table
2315
2316 Not all object formats support this option. In particular the ELF
2317 format does not use it.
2318
2319 @item -r
2320 @itemx --reloc
2321 @cindex relocation entries, in object file
2322 Print the relocation entries of the file. If used with @option{-d} or
2323 @option{-D}, the relocations are printed interspersed with the
2324 disassembly.
2325
2326 @item -R
2327 @itemx --dynamic-reloc
2328 @cindex dynamic relocation entries, in object file
2329 Print the dynamic relocation entries of the file. This is only
2330 meaningful for dynamic objects, such as certain types of shared
2331 libraries. As for @option{-r}, if used with @option{-d} or
2332 @option{-D}, the relocations are printed interspersed with the
2333 disassembly.
2334
2335 @item -s
2336 @itemx --full-contents
2337 @cindex sections, full contents
2338 @cindex object file sections
2339 Display the full contents of any sections requested. By default all
2340 non-empty sections are displayed.
2341
2342 @item -S
2343 @itemx --source
2344 @cindex source disassembly
2345 @cindex disassembly, with source
2346 Display source code intermixed with disassembly, if possible. Implies
2347 @option{-d}.
2348
2349 @item --prefix=@var{prefix}
2350 @cindex Add prefix to absolute paths
2351 Specify @var{prefix} to add to the absolute paths when used with
2352 @option{-S}.
2353
2354 @item --prefix-strip=@var{level}
2355 @cindex Strip absolute paths
2356 Indicate how many initial directory names to strip off the hardwired
2357 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2358
2359 @item --show-raw-insn
2360 When disassembling instructions, print the instruction in hex as well as
2361 in symbolic form. This is the default except when
2362 @option{--prefix-addresses} is used.
2363
2364 @item --no-show-raw-insn
2365 When disassembling instructions, do not print the instruction bytes.
2366 This is the default when @option{--prefix-addresses} is used.
2367
2368 @item --insn-width=@var{width}
2369 @cindex Instruction width
2370 Display @var{width} bytes on a single line when disassembling
2371 instructions.
2372
2373 @item -W[lLiaprmfFsoRt]
2374 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
2375 @itemx --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
2376 @itemx --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2377 @itemx --dwarf[=trace_aranges,=gdb_index]
2378 @cindex DWARF
2379 @cindex debug symbols
2380 Displays the contents of the debug sections in the file, if any are
2381 present. If one of the optional letters or words follows the switch
2382 then only data found in those specific sections will be dumped.
2383
2384 Note that there is no single letter option to display the content of
2385 trace sections or .gdb_index.
2386
2387 Note: the output from the @option{=info} option can also be affected
2388 by the options @option{--dwarf-depth}, the @option{--dwarf-start} and
2389 the @option{--dwarf-check}.
2390
2391 @item --dwarf-depth=@var{n}
2392 Limit the dump of the @code{.debug_info} section to @var{n} children.
2393 This is only useful with @option{--dwarf=info}. The default is
2394 to print all DIEs; the special value 0 for @var{n} will also have this
2395 effect.
2396
2397 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
2398 levels will not be printed. The range for @var{n} is zero-based.
2399
2400 @item --dwarf-start=@var{n}
2401 Print only DIEs beginning with the DIE numbered @var{n}. This is only
2402 useful with @option{--dwarf=info}.
2403
2404 If specified, this option will suppress printing of any header
2405 information and all DIEs before the DIE numbered @var{n}. Only
2406 siblings and children of the specified DIE will be printed.
2407
2408 This can be used in conjunction with @option{--dwarf-depth}.
2409
2410 @item --dwarf-check
2411 Enable additional checks for consistency of Dwarf information.
2412
2413 @item -G
2414 @itemx --stabs
2415 @cindex stab
2416 @cindex .stab
2417 @cindex debug symbols
2418 @cindex ELF object file format
2419 Display the full contents of any sections requested. Display the
2420 contents of the .stab and .stab.index and .stab.excl sections from an
2421 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2422 @code{.stab} debugging symbol-table entries are carried in an ELF
2423 section. In most other file formats, debugging symbol-table entries are
2424 interleaved with linkage symbols, and are visible in the @option{--syms}
2425 output.
2426
2427 @item --start-address=@var{address}
2428 @cindex start-address
2429 Start displaying data at the specified address. This affects the output
2430 of the @option{-d}, @option{-r} and @option{-s} options.
2431
2432 @item --stop-address=@var{address}
2433 @cindex stop-address
2434 Stop displaying data at the specified address. This affects the output
2435 of the @option{-d}, @option{-r} and @option{-s} options.
2436
2437 @item -t
2438 @itemx --syms
2439 @cindex symbol table entries, printing
2440 Print the symbol table entries of the file.
2441 This is similar to the information provided by the @samp{nm} program,
2442 although the display format is different. The format of the output
2443 depends upon the format of the file being dumped, but there are two main
2444 types. One looks like this:
2445
2446 @smallexample
2447 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2448 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2449 @end smallexample
2450
2451 where the number inside the square brackets is the number of the entry
2452 in the symbol table, the @var{sec} number is the section number, the
2453 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2454 symbol's type, the @var{scl} number is the symbol's storage class and
2455 the @var{nx} value is the number of auxilary entries associated with
2456 the symbol. The last two fields are the symbol's value and its name.
2457
2458 The other common output format, usually seen with ELF based files,
2459 looks like this:
2460
2461 @smallexample
2462 00000000 l d .bss 00000000 .bss
2463 00000000 g .text 00000000 fred
2464 @end smallexample
2465
2466 Here the first number is the symbol's value (sometimes refered to as
2467 its address). The next field is actually a set of characters and
2468 spaces indicating the flag bits that are set on the symbol. These
2469 characters are described below. Next is the section with which the
2470 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2471 not connected with any section), or @emph{*UND*} if the section is
2472 referenced in the file being dumped, but not defined there.
2473
2474 After the section name comes another field, a number, which for common
2475 symbols is the alignment and for other symbol is the size. Finally
2476 the symbol's name is displayed.
2477
2478 The flag characters are divided into 7 groups as follows:
2479 @table @code
2480 @item l
2481 @itemx g
2482 @itemx u
2483 @itemx !
2484 The symbol is a local (l), global (g), unique global (u), neither
2485 global nor local (a space) or both global and local (!). A
2486 symbol can be neither local or global for a variety of reasons, e.g.,
2487 because it is used for debugging, but it is probably an indication of
2488 a bug if it is ever both local and global. Unique global symbols are
2489 a GNU extension to the standard set of ELF symbol bindings. For such
2490 a symbol the dynamic linker will make sure that in the entire process
2491 there is just one symbol with this name and type in use.
2492
2493 @item w
2494 The symbol is weak (w) or strong (a space).
2495
2496 @item C
2497 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2498
2499 @item W
2500 The symbol is a warning (W) or a normal symbol (a space). A warning
2501 symbol's name is a message to be displayed if the symbol following the
2502 warning symbol is ever referenced.
2503
2504 @item I
2505 @item i
2506 The symbol is an indirect reference to another symbol (I), a function
2507 to be evaluated during reloc processing (i) or a normal symbol (a
2508 space).
2509
2510 @item d
2511 @itemx D
2512 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2513 normal symbol (a space).
2514
2515 @item F
2516 @item f
2517 @item O
2518 The symbol is the name of a function (F) or a file (f) or an object
2519 (O) or just a normal symbol (a space).
2520 @end table
2521
2522 @item -T
2523 @itemx --dynamic-syms
2524 @cindex dynamic symbol table entries, printing
2525 Print the dynamic symbol table entries of the file. This is only
2526 meaningful for dynamic objects, such as certain types of shared
2527 libraries. This is similar to the information provided by the @samp{nm}
2528 program when given the @option{-D} (@option{--dynamic}) option.
2529
2530 @item --special-syms
2531 When displaying symbols include those which the target considers to be
2532 special in some way and which would not normally be of interest to the
2533 user.
2534
2535 @item -V
2536 @itemx --version
2537 Print the version number of @command{objdump} and exit.
2538
2539 @item -x
2540 @itemx --all-headers
2541 @cindex all header information, object file
2542 @cindex header information, all
2543 Display all available header information, including the symbol table and
2544 relocation entries. Using @option{-x} is equivalent to specifying all of
2545 @option{-a -f -h -p -r -t}.
2546
2547 @item -w
2548 @itemx --wide
2549 @cindex wide output, printing
2550 Format some lines for output devices that have more than 80 columns.
2551 Also do not truncate symbol names when they are displayed.
2552
2553 @item -z
2554 @itemx --disassemble-zeroes
2555 Normally the disassembly output will skip blocks of zeroes. This
2556 option directs the disassembler to disassemble those blocks, just like
2557 any other data.
2558 @end table
2559
2560 @c man end
2561
2562 @ignore
2563 @c man begin SEEALSO objdump
2564 nm(1), readelf(1), and the Info entries for @file{binutils}.
2565 @c man end
2566 @end ignore
2567
2568 @node ranlib
2569 @chapter ranlib
2570
2571 @kindex ranlib
2572 @cindex archive contents
2573 @cindex symbol index
2574
2575 @c man title ranlib generate index to archive.
2576
2577 @smallexample
2578 @c man begin SYNOPSIS ranlib
2579 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2580 @c man end
2581 @end smallexample
2582
2583 @c man begin DESCRIPTION ranlib
2584
2585 @command{ranlib} generates an index to the contents of an archive and
2586 stores it in the archive. The index lists each symbol defined by a
2587 member of an archive that is a relocatable object file.
2588
2589 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2590
2591 An archive with such an index speeds up linking to the library and
2592 allows routines in the library to call each other without regard to
2593 their placement in the archive.
2594
2595 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2596 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2597 @xref{ar}.
2598
2599 @c man end
2600
2601 @c man begin OPTIONS ranlib
2602
2603 @table @env
2604 @item -h
2605 @itemx -H
2606 @itemx --help
2607 Show usage information for @command{ranlib}.
2608
2609 @item -v
2610 @itemx -V
2611 @itemx --version
2612 Show the version number of @command{ranlib}.
2613
2614 @item -D
2615 @cindex deterministic archives
2616 @kindex --enable-deterministic-archives
2617 Operate in @emph{deterministic} mode. The symbol map archive member's
2618 header will show zero for the UID, GID, and timestamp. When this
2619 option is used, multiple runs will produce identical output files.
2620
2621 If @file{binutils} was configured with
2622 @option{--enable-deterministic-archives}, then this mode is on by
2623 default. It can be disabled with the @samp{-U} option, described
2624 below.
2625
2626 @item -t
2627 Update the timestamp of the symbol map of an archive.
2628
2629 @item -U
2630 @cindex deterministic archives
2631 @kindex --enable-deterministic-archives
2632 Do @emph{not} operate in @emph{deterministic} mode. This is the
2633 inverse of the @samp{-D} option, above: the archive index will get
2634 actual UID, GID, timestamp, and file mode values.
2635
2636 If @file{binutils} was configured @emph{without}
2637 @option{--enable-deterministic-archives}, then this mode is on by
2638 default.
2639
2640 @end table
2641
2642 @c man end
2643
2644 @ignore
2645 @c man begin SEEALSO ranlib
2646 ar(1), nm(1), and the Info entries for @file{binutils}.
2647 @c man end
2648 @end ignore
2649
2650 @node size
2651 @chapter size
2652
2653 @kindex size
2654 @cindex section sizes
2655
2656 @c man title size list section sizes and total size.
2657
2658 @smallexample
2659 @c man begin SYNOPSIS size
2660 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2661 [@option{--help}]
2662 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2663 [@option{--common}]
2664 [@option{-t}|@option{--totals}]
2665 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2666 [@var{objfile}@dots{}]
2667 @c man end
2668 @end smallexample
2669
2670 @c man begin DESCRIPTION size
2671
2672 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2673 size---for each of the object or archive files @var{objfile} in its
2674 argument list. By default, one line of output is generated for each
2675 object file or each module in an archive.
2676
2677 @var{objfile}@dots{} are the object files to be examined.
2678 If none are specified, the file @code{a.out} will be used.
2679
2680 @c man end
2681
2682 @c man begin OPTIONS size
2683
2684 The command line options have the following meanings:
2685
2686 @table @env
2687 @item -A
2688 @itemx -B
2689 @itemx --format=@var{compatibility}
2690 @cindex @command{size} display format
2691 Using one of these options, you can choose whether the output from @sc{gnu}
2692 @command{size} resembles output from System V @command{size} (using @option{-A},
2693 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2694 @option{--format=berkeley}). The default is the one-line format similar to
2695 Berkeley's.
2696 @c Bonus for doc-source readers: you can also say --format=strange (or
2697 @c anything else that starts with 's') for sysv, and --format=boring (or
2698 @c anything else that starts with 'b') for Berkeley.
2699
2700 Here is an example of the Berkeley (default) format of output from
2701 @command{size}:
2702 @smallexample
2703 $ size --format=Berkeley ranlib size
2704 text data bss dec hex filename
2705 294880 81920 11592 388392 5ed28 ranlib
2706 294880 81920 11888 388688 5ee50 size
2707 @end smallexample
2708
2709 @noindent
2710 This is the same data, but displayed closer to System V conventions:
2711
2712 @smallexample
2713 $ size --format=SysV ranlib size
2714 ranlib :
2715 section size addr
2716 .text 294880 8192
2717 .data 81920 303104
2718 .bss 11592 385024
2719 Total 388392
2720
2721
2722 size :
2723 section size addr
2724 .text 294880 8192
2725 .data 81920 303104
2726 .bss 11888 385024
2727 Total 388688
2728 @end smallexample
2729
2730 @item --help
2731 Show a summary of acceptable arguments and options.
2732
2733 @item -d
2734 @itemx -o
2735 @itemx -x
2736 @itemx --radix=@var{number}
2737 @cindex @command{size} number format
2738 @cindex radix for section sizes
2739 Using one of these options, you can control whether the size of each
2740 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2741 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2742 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2743 values (8, 10, 16) are supported. The total size is always given in two
2744 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2745 octal and hexadecimal if you're using @option{-o}.
2746
2747 @item --common
2748 Print total size of common symbols in each file. When using Berkeley
2749 format these are included in the bss size.
2750
2751 @item -t
2752 @itemx --totals
2753 Show totals of all objects listed (Berkeley format listing mode only).
2754
2755 @item --target=@var{bfdname}
2756 @cindex object code format
2757 Specify that the object-code format for @var{objfile} is
2758 @var{bfdname}. This option may not be necessary; @command{size} can
2759 automatically recognize many formats.
2760 @xref{Target Selection}, for more information.
2761
2762 @item -V
2763 @itemx --version
2764 Display the version number of @command{size}.
2765 @end table
2766
2767 @c man end
2768
2769 @ignore
2770 @c man begin SEEALSO size
2771 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2772 @c man end
2773 @end ignore
2774
2775 @node strings
2776 @chapter strings
2777 @kindex strings
2778 @cindex listings strings
2779 @cindex printing strings
2780 @cindex strings, printing
2781
2782 @c man title strings print the strings of printable characters in files.
2783
2784 @smallexample
2785 @c man begin SYNOPSIS strings
2786 strings [@option{-afovV}] [@option{-}@var{min-len}]
2787 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2788 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2789 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2790 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2791 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2792 [@option{-w}] [@option{--include-all-whitespace}]
2793 [@option{-s}] [@option{--output-separator}@var{sep_string}]
2794 [@option{--help}] [@option{--version}] @var{file}@dots{}
2795 @c man end
2796 @end smallexample
2797
2798 @c man begin DESCRIPTION strings
2799
2800 For each @var{file} given, @sc{gnu} @command{strings} prints the
2801 printable character sequences that are at least 4 characters long (or
2802 the number given with the options below) and are followed by an
2803 unprintable character.
2804
2805 Depending upon how the strings program was configured it will default
2806 to either displaying all the printable sequences that it can find in
2807 each file, or only those sequences that are in loadable, initialized
2808 data sections. If the file type in unrecognizable, or if strings is
2809 reading from stdin then it will always display all of the printable
2810 sequences that it can find.
2811
2812 For backwards compatibility any file that occurs after a command line
2813 option of just @option{-} will also be scanned in full, regardless of
2814 the presence of any @option{-d} option.
2815
2816 @command{strings} is mainly useful for determining the contents of
2817 non-text files.
2818
2819 @c man end
2820
2821 @c man begin OPTIONS strings
2822
2823 @table @env
2824 @item -a
2825 @itemx --all
2826 @itemx -
2827 Scan the whole file, regardless of what sections it contains or
2828 whether those sections are loaded or initialized. Normally this is
2829 the default behaviour, but strings can be configured so that the
2830 @option{-d} is the default instead.
2831
2832 The @option{-} option is position dependent and forces strings to
2833 perform full scans of any file that is mentioned after the @option{-}
2834 on the command line, even if the @option{-d} option has been
2835 specified.
2836
2837 @item -d
2838 @itemx --data
2839 Only print strings from initialized, loaded data sections in the
2840 file. This may reduce the amount of garbage in the output, but it
2841 also exposes the strings program to any security flaws that may be
2842 present in the BFD library used to scan and load sections. Strings
2843 can be configured so that this option is the default behaviour. In
2844 such cases the @option{-a} option can be used to avoid using the BFD
2845 library and instead just print all of the strings found in the file.
2846
2847 @item -f
2848 @itemx --print-file-name
2849 Print the name of the file before each string.
2850
2851 @item --help
2852 Print a summary of the program usage on the standard output and exit.
2853
2854 @item -@var{min-len}
2855 @itemx -n @var{min-len}
2856 @itemx --bytes=@var{min-len}
2857 Print sequences of characters that are at least @var{min-len} characters
2858 long, instead of the default 4.
2859
2860 @item -o
2861 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2862 act like @samp{-t d} instead. Since we can not be compatible with both
2863 ways, we simply chose one.
2864
2865 @item -t @var{radix}
2866 @itemx --radix=@var{radix}
2867 Print the offset within the file before each string. The single
2868 character argument specifies the radix of the offset---@samp{o} for
2869 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2870
2871 @item -e @var{encoding}
2872 @itemx --encoding=@var{encoding}
2873 Select the character encoding of the strings that are to be found.
2874 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2875 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2876 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2877 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2878 littleendian. Useful for finding wide character strings. (@samp{l}
2879 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
2880
2881 @item -T @var{bfdname}
2882 @itemx --target=@var{bfdname}
2883 @cindex object code format
2884 Specify an object code format other than your system's default format.
2885 @xref{Target Selection}, for more information.
2886
2887 @item -v
2888 @itemx -V
2889 @itemx --version
2890 Print the program version number on the standard output and exit.
2891
2892 @item -w
2893 @itemx --include-all-whitespace
2894 By default tab and space characters are included in the strings that
2895 are displayed, but other whitespace characters, such a newlines and
2896 carriage returns, are not. The @option{-w} option changes this so
2897 that all whitespace characters are considered to be part of a string.
2898
2899 @item -s
2900 @itemx --output-separator
2901 By default, output strings are delimited by a new-line. This option
2902 allows you to supply any string to be used as the output record
2903 separator. Useful with --include-all-whitespace where strings
2904 may contain new-lines internally.
2905 @end table
2906
2907 @c man end
2908
2909 @ignore
2910 @c man begin SEEALSO strings
2911 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2912 and the Info entries for @file{binutils}.
2913 @c man end
2914 @end ignore
2915
2916 @node strip
2917 @chapter strip
2918
2919 @kindex strip
2920 @cindex removing symbols
2921 @cindex discarding symbols
2922 @cindex symbols, discarding
2923
2924 @c man title strip Discard symbols from object files.
2925
2926 @smallexample
2927 @c man begin SYNOPSIS strip
2928 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2929 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2930 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2931 [@option{-s}|@option{--strip-all}]
2932 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2933 [@option{--strip-dwo}]
2934 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2935 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2936 [@option{-w}|@option{--wildcard}]
2937 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2938 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2939 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2940 [@option{-D}|@option{--enable-deterministic-archives}]
2941 [@option{-U}|@option{--disable-deterministic-archives}]
2942 [@option{--keep-file-symbols}]
2943 [@option{--only-keep-debug}]
2944 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2945 [@option{--help}] [@option{--info}]
2946 @var{objfile}@dots{}
2947 @c man end
2948 @end smallexample
2949
2950 @c man begin DESCRIPTION strip
2951
2952 @sc{gnu} @command{strip} discards all symbols from object files
2953 @var{objfile}. The list of object files may include archives.
2954 At least one object file must be given.
2955
2956 @command{strip} modifies the files named in its argument,
2957 rather than writing modified copies under different names.
2958
2959 @c man end
2960
2961 @c man begin OPTIONS strip
2962
2963 @table @env
2964 @item -F @var{bfdname}
2965 @itemx --target=@var{bfdname}
2966 Treat the original @var{objfile} as a file with the object
2967 code format @var{bfdname}, and rewrite it in the same format.
2968 @xref{Target Selection}, for more information.
2969
2970 @item --help
2971 Show a summary of the options to @command{strip} and exit.
2972
2973 @item --info
2974 Display a list showing all architectures and object formats available.
2975
2976 @item -I @var{bfdname}
2977 @itemx --input-target=@var{bfdname}
2978 Treat the original @var{objfile} as a file with the object
2979 code format @var{bfdname}.
2980 @xref{Target Selection}, for more information.
2981
2982 @item -O @var{bfdname}
2983 @itemx --output-target=@var{bfdname}
2984 Replace @var{objfile} with a file in the output format @var{bfdname}.
2985 @xref{Target Selection}, for more information.
2986
2987 @item -R @var{sectionname}
2988 @itemx --remove-section=@var{sectionname}
2989 Remove any section named @var{sectionname} from the output file, in
2990 addition to whatever sections would otherwise be removed. This
2991 option may be given more than once. Note that using this option
2992 inappropriately may make the output file unusable. The wildcard
2993 character @samp{*} may be given at the end of @var{sectionname}. If
2994 so, then any section starting with @var{sectionname} will be removed.
2995
2996 @item -s
2997 @itemx --strip-all
2998 Remove all symbols.
2999
3000 @item -g
3001 @itemx -S
3002 @itemx -d
3003 @itemx --strip-debug
3004 Remove debugging symbols only.
3005
3006 @item --strip-dwo
3007 Remove the contents of all DWARF .dwo sections, leaving the
3008 remaining debugging sections and all symbols intact.
3009 See the description of this option in the @command{objcopy} section
3010 for more information.
3011
3012 @item --strip-unneeded
3013 Remove all symbols that are not needed for relocation processing.
3014
3015 @item -K @var{symbolname}
3016 @itemx --keep-symbol=@var{symbolname}
3017 When stripping symbols, keep symbol @var{symbolname} even if it would
3018 normally be stripped. This option may be given more than once.
3019
3020 @item -N @var{symbolname}
3021 @itemx --strip-symbol=@var{symbolname}
3022 Remove symbol @var{symbolname} from the source file. This option may be
3023 given more than once, and may be combined with strip options other than
3024 @option{-K}.
3025
3026 @item -o @var{file}
3027 Put the stripped output in @var{file}, rather than replacing the
3028 existing file. When this argument is used, only one @var{objfile}
3029 argument may be specified.
3030
3031 @item -p
3032 @itemx --preserve-dates
3033 Preserve the access and modification dates of the file.
3034
3035 @item -D
3036 @itemx --enable-deterministic-archives
3037 @cindex deterministic archives
3038 @kindex --enable-deterministic-archives
3039 Operate in @emph{deterministic} mode. When copying archive members
3040 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3041 and use consistent file modes for all files.
3042
3043 If @file{binutils} was configured with
3044 @option{--enable-deterministic-archives}, then this mode is on by default.
3045 It can be disabled with the @samp{-U} option, below.
3046
3047 @item -U
3048 @itemx --disable-deterministic-archives
3049 @cindex deterministic archives
3050 @kindex --enable-deterministic-archives
3051 Do @emph{not} operate in @emph{deterministic} mode. This is the
3052 inverse of the @option{-D} option, above: when copying archive members
3053 and writing the archive index, use their actual UID, GID, timestamp,
3054 and file mode values.
3055
3056 This is the default unless @file{binutils} was configured with
3057 @option{--enable-deterministic-archives}.
3058
3059 @item -w
3060 @itemx --wildcard
3061 Permit regular expressions in @var{symbolname}s used in other command
3062 line options. The question mark (?), asterisk (*), backslash (\) and
3063 square brackets ([]) operators can be used anywhere in the symbol
3064 name. If the first character of the symbol name is the exclamation
3065 point (!) then the sense of the switch is reversed for that symbol.
3066 For example:
3067
3068 @smallexample
3069 -w -K !foo -K fo*
3070 @end smallexample
3071
3072 would cause strip to only keep symbols that start with the letters
3073 ``fo'', but to discard the symbol ``foo''.
3074
3075 @item -x
3076 @itemx --discard-all
3077 Remove non-global symbols.
3078
3079 @item -X
3080 @itemx --discard-locals
3081 Remove compiler-generated local symbols.
3082 (These usually start with @samp{L} or @samp{.}.)
3083
3084 @item --keep-file-symbols
3085 When stripping a file, perhaps with @option{--strip-debug} or
3086 @option{--strip-unneeded}, retain any symbols specifying source file names,
3087 which would otherwise get stripped.
3088
3089 @item --only-keep-debug
3090 Strip a file, emptying the contents of any sections that would not be
3091 stripped by @option{--strip-debug} and leaving the debugging sections
3092 intact. In ELF files, this preserves all the note sections in the
3093 output as well.
3094
3095 Note - the section headers of the stripped sections are preserved,
3096 including their sizes, but the contents of the section are discarded.
3097 The section headers are preserved so that other tools can match up the
3098 debuginfo file with the real executable, even if that executable has
3099 been relocated to a different address space.
3100
3101 The intention is that this option will be used in conjunction with
3102 @option{--add-gnu-debuglink} to create a two part executable. One a
3103 stripped binary which will occupy less space in RAM and in a
3104 distribution and the second a debugging information file which is only
3105 needed if debugging abilities are required. The suggested procedure
3106 to create these files is as follows:
3107
3108 @enumerate
3109 @item Link the executable as normal. Assuming that is is called
3110 @code{foo} then...
3111 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3112 create a file containing the debugging info.
3113 @item Run @code{objcopy --strip-debug foo} to create a
3114 stripped executable.
3115 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3116 to add a link to the debugging info into the stripped executable.
3117 @end enumerate
3118
3119 Note---the choice of @code{.dbg} as an extension for the debug info
3120 file is arbitrary. Also the @code{--only-keep-debug} step is
3121 optional. You could instead do this:
3122
3123 @enumerate
3124 @item Link the executable as normal.
3125 @item Copy @code{foo} to @code{foo.full}
3126 @item Run @code{strip --strip-debug foo}
3127 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3128 @end enumerate
3129
3130 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3131 full executable. It does not have to be a file created by the
3132 @option{--only-keep-debug} switch.
3133
3134 Note---this switch is only intended for use on fully linked files. It
3135 does not make sense to use it on object files where the debugging
3136 information may be incomplete. Besides the gnu_debuglink feature
3137 currently only supports the presence of one filename containing
3138 debugging information, not multiple filenames on a one-per-object-file
3139 basis.
3140
3141 @item -V
3142 @itemx --version
3143 Show the version number for @command{strip}.
3144
3145 @item -v
3146 @itemx --verbose
3147 Verbose output: list all object files modified. In the case of
3148 archives, @samp{strip -v} lists all members of the archive.
3149 @end table
3150
3151 @c man end
3152
3153 @ignore
3154 @c man begin SEEALSO strip
3155 the Info entries for @file{binutils}.
3156 @c man end
3157 @end ignore
3158
3159 @node c++filt, addr2line, strip, Top
3160 @chapter c++filt
3161
3162 @kindex c++filt
3163 @cindex demangling C++ symbols
3164
3165 @c man title cxxfilt Demangle C++ and Java symbols.
3166
3167 @smallexample
3168 @c man begin SYNOPSIS cxxfilt
3169 c++filt [@option{-_}|@option{--strip-underscore}]
3170 [@option{-n}|@option{--no-strip-underscore}]
3171 [@option{-p}|@option{--no-params}]
3172 [@option{-t}|@option{--types}]
3173 [@option{-i}|@option{--no-verbose}]
3174 [@option{-s} @var{format}|@option{--format=}@var{format}]
3175 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3176 @c man end
3177 @end smallexample
3178
3179 @c man begin DESCRIPTION cxxfilt
3180
3181 @kindex cxxfilt
3182 The C++ and Java languages provide function overloading, which means
3183 that you can write many functions with the same name, providing that
3184 each function takes parameters of different types. In order to be
3185 able to distinguish these similarly named functions C++ and Java
3186 encode them into a low-level assembler name which uniquely identifies
3187 each different version. This process is known as @dfn{mangling}. The
3188 @command{c++filt}
3189 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3190 MS-DOS this program is named @command{CXXFILT}.}
3191 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3192 names into user-level names so that they can be read.
3193
3194 Every alphanumeric word (consisting of letters, digits, underscores,
3195 dollars, or periods) seen in the input is a potential mangled name.
3196 If the name decodes into a C++ name, the C++ name replaces the
3197 low-level name in the output, otherwise the original word is output.
3198 In this way you can pass an entire assembler source file, containing
3199 mangled names, through @command{c++filt} and see the same source file
3200 containing demangled names.
3201
3202 You can also use @command{c++filt} to decipher individual symbols by
3203 passing them on the command line:
3204
3205 @example
3206 c++filt @var{symbol}
3207 @end example
3208
3209 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3210 names from the standard input instead. All the results are printed on
3211 the standard output. The difference between reading names from the
3212 command line versus reading names from the standard input is that
3213 command line arguments are expected to be just mangled names and no
3214 checking is performed to separate them from surrounding text. Thus
3215 for example:
3216
3217 @smallexample
3218 c++filt -n _Z1fv
3219 @end smallexample
3220
3221 will work and demangle the name to ``f()'' whereas:
3222
3223 @smallexample
3224 c++filt -n _Z1fv,
3225 @end smallexample
3226
3227 will not work. (Note the extra comma at the end of the mangled
3228 name which makes it invalid). This command however will work:
3229
3230 @smallexample
3231 echo _Z1fv, | c++filt -n
3232 @end smallexample
3233
3234 and will display ``f(),'', i.e., the demangled name followed by a
3235 trailing comma. This behaviour is because when the names are read
3236 from the standard input it is expected that they might be part of an
3237 assembler source file where there might be extra, extraneous
3238 characters trailing after a mangled name. For example:
3239
3240 @smallexample
3241 .type _Z1fv, @@function
3242 @end smallexample
3243
3244 @c man end
3245
3246 @c man begin OPTIONS cxxfilt
3247
3248 @table @env
3249 @item -_
3250 @itemx --strip-underscore
3251 On some systems, both the C and C++ compilers put an underscore in front
3252 of every name. For example, the C name @code{foo} gets the low-level
3253 name @code{_foo}. This option removes the initial underscore. Whether
3254 @command{c++filt} removes the underscore by default is target dependent.
3255
3256 @item -n
3257 @itemx --no-strip-underscore
3258 Do not remove the initial underscore.
3259
3260 @item -p
3261 @itemx --no-params
3262 When demangling the name of a function, do not display the types of
3263 the function's parameters.
3264
3265 @item -t
3266 @itemx --types
3267 Attempt to demangle types as well as function names. This is disabled
3268 by default since mangled types are normally only used internally in
3269 the compiler, and they can be confused with non-mangled names. For example,
3270 a function called ``a'' treated as a mangled type name would be
3271 demangled to ``signed char''.
3272
3273 @item -i
3274 @itemx --no-verbose
3275 Do not include implementation details (if any) in the demangled
3276 output.
3277
3278 @item -s @var{format}
3279 @itemx --format=@var{format}
3280 @command{c++filt} can decode various methods of mangling, used by
3281 different compilers. The argument to this option selects which
3282 method it uses:
3283
3284 @table @code
3285 @item auto
3286 Automatic selection based on executable (the default method)
3287 @item gnu
3288 the one used by the @sc{gnu} C++ compiler (g++)
3289 @item lucid
3290 the one used by the Lucid compiler (lcc)
3291 @item arm
3292 the one specified by the C++ Annotated Reference Manual
3293 @item hp
3294 the one used by the HP compiler (aCC)
3295 @item edg
3296 the one used by the EDG compiler
3297 @item gnu-v3
3298 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3299 @item java
3300 the one used by the @sc{gnu} Java compiler (gcj)
3301 @item gnat
3302 the one used by the @sc{gnu} Ada compiler (GNAT).
3303 @end table
3304
3305 @item --help
3306 Print a summary of the options to @command{c++filt} and exit.
3307
3308 @item --version
3309 Print the version number of @command{c++filt} and exit.
3310 @end table
3311
3312 @c man end
3313
3314 @ignore
3315 @c man begin SEEALSO cxxfilt
3316 the Info entries for @file{binutils}.
3317 @c man end
3318 @end ignore
3319
3320 @quotation
3321 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3322 user interface are subject to change in future releases. In particular,
3323 a command-line option may be required in the future to decode a name
3324 passed as an argument on the command line; in other words,
3325
3326 @example
3327 c++filt @var{symbol}
3328 @end example
3329
3330 @noindent
3331 may in a future release become
3332
3333 @example
3334 c++filt @var{option} @var{symbol}
3335 @end example
3336 @end quotation
3337
3338 @node addr2line
3339 @chapter addr2line
3340
3341 @kindex addr2line
3342 @cindex address to file name and line number
3343
3344 @c man title addr2line convert addresses into file names and line numbers.
3345
3346 @smallexample
3347 @c man begin SYNOPSIS addr2line
3348 addr2line [@option{-a}|@option{--addresses}]
3349 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3350 [@option{-C}|@option{--demangle}[=@var{style}]]
3351 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3352 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3353 [@option{-i}|@option{--inlines}]
3354 [@option{-p}|@option{--pretty-print}]
3355 [@option{-j}|@option{--section=}@var{name}]
3356 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3357 [addr addr @dots{}]
3358 @c man end
3359 @end smallexample
3360
3361 @c man begin DESCRIPTION addr2line
3362
3363 @command{addr2line} translates addresses into file names and line numbers.
3364 Given an address in an executable or an offset in a section of a relocatable
3365 object, it uses the debugging information to figure out which file name and
3366 line number are associated with it.
3367
3368 The executable or relocatable object to use is specified with the @option{-e}
3369 option. The default is the file @file{a.out}. The section in the relocatable
3370 object to use is specified with the @option{-j} option.
3371
3372 @command{addr2line} has two modes of operation.
3373
3374 In the first, hexadecimal addresses are specified on the command line,
3375 and @command{addr2line} displays the file name and line number for each
3376 address.
3377
3378 In the second, @command{addr2line} reads hexadecimal addresses from
3379 standard input, and prints the file name and line number for each
3380 address on standard output. In this mode, @command{addr2line} may be used
3381 in a pipe to convert dynamically chosen addresses.
3382
3383 The format of the output is @samp{FILENAME:LINENO}. By default
3384 each input address generates one line of output.
3385
3386 Two options can generate additional lines before each
3387 @samp{FILENAME:LINENO} line (in that order).
3388
3389 If the @option{-a} option is used then a line with the input address
3390 is displayed.
3391
3392 If the @option{-f} option is used, then a line with the
3393 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3394 containing the address.
3395
3396 One option can generate additional lines after the
3397 @samp{FILENAME:LINENO} line.
3398
3399 If the @option{-i} option is used and the code at the given address is
3400 present there because of inlining by the compiler then additional
3401 lines are displayed afterwards. One or two extra lines (if the
3402 @option{-f} option is used) are displayed for each inlined function.
3403
3404 Alternatively if the @option{-p} option is used then each input
3405 address generates a single, long, output line containing the address,
3406 the function name, the file name and the line number. If the
3407 @option{-i} option has also been used then any inlined functions will
3408 be displayed in the same manner, but on separate lines, and prefixed
3409 by the text @samp{(inlined by)}.
3410
3411 If the file name or function name can not be determined,
3412 @command{addr2line} will print two question marks in their place. If the
3413 line number can not be determined, @command{addr2line} will print 0.
3414
3415 @c man end
3416
3417 @c man begin OPTIONS addr2line
3418
3419 The long and short forms of options, shown here as alternatives, are
3420 equivalent.
3421
3422 @table @env
3423 @item -a
3424 @itemx --addresses
3425 Display the address before the function name, file and line number
3426 information. The address is printed with a @samp{0x} prefix to easily
3427 identify it.
3428
3429 @item -b @var{bfdname}
3430 @itemx --target=@var{bfdname}
3431 @cindex object code format
3432 Specify that the object-code format for the object files is
3433 @var{bfdname}.
3434
3435 @item -C
3436 @itemx --demangle[=@var{style}]
3437 @cindex demangling in objdump
3438 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3439 Besides removing any initial underscore prepended by the system, this
3440 makes C++ function names readable. Different compilers have different
3441 mangling styles. The optional demangling style argument can be used to
3442 choose an appropriate demangling style for your compiler. @xref{c++filt},
3443 for more information on demangling.
3444
3445 @item -e @var{filename}
3446 @itemx --exe=@var{filename}
3447 Specify the name of the executable for which addresses should be
3448 translated. The default file is @file{a.out}.
3449
3450 @item -f
3451 @itemx --functions
3452 Display function names as well as file and line number information.
3453
3454 @item -s
3455 @itemx --basenames
3456 Display only the base of each file name.
3457
3458 @item -i
3459 @itemx --inlines
3460 If the address belongs to a function that was inlined, the source
3461 information for all enclosing scopes back to the first non-inlined
3462 function will also be printed. For example, if @code{main} inlines
3463 @code{callee1} which inlines @code{callee2}, and address is from
3464 @code{callee2}, the source information for @code{callee1} and @code{main}
3465 will also be printed.
3466
3467 @item -j
3468 @itemx --section
3469 Read offsets relative to the specified section instead of absolute addresses.
3470
3471 @item -p
3472 @itemx --pretty-print
3473 Make the output more human friendly: each location are printed on one line.
3474 If option @option{-i} is specified, lines for all enclosing scopes are
3475 prefixed with @samp{(inlined by)}.
3476 @end table
3477
3478 @c man end
3479
3480 @ignore
3481 @c man begin SEEALSO addr2line
3482 Info entries for @file{binutils}.
3483 @c man end
3484 @end ignore
3485
3486 @node nlmconv
3487 @chapter nlmconv
3488
3489 @command{nlmconv} converts a relocatable object file into a NetWare
3490 Loadable Module.
3491
3492 @ignore
3493 @command{nlmconv} currently works with @samp{i386} object
3494 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3495 object files in @sc{elf}, or @code{a.out} format@footnote{
3496 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3497 format in the Binary File Descriptor library. It has only been tested
3498 with the above formats.}.
3499 @end ignore
3500
3501 @quotation
3502 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3503 utilities, since it is only useful for NLM targets.
3504 @end quotation
3505
3506 @c man title nlmconv converts object code into an NLM.
3507
3508 @smallexample
3509 @c man begin SYNOPSIS nlmconv
3510 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3511 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3512 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3513 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3514 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3515 @var{infile} @var{outfile}
3516 @c man end
3517 @end smallexample
3518
3519 @c man begin DESCRIPTION nlmconv
3520
3521 @command{nlmconv} converts the relocatable @samp{i386} object file
3522 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3523 reading @var{headerfile} for NLM header information. For instructions
3524 on writing the NLM command file language used in header files, see the
3525 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3526 Development and Tools Overview}, which is part of the NLM Software
3527 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3528 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3529 @var{infile};
3530 @ifclear man
3531 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3532 @end ifclear
3533
3534 @command{nlmconv} can perform a link step. In other words, you can list
3535 more than one object file for input if you list them in the definitions
3536 file (rather than simply specifying one input file on the command line).
3537 In this case, @command{nlmconv} calls the linker for you.
3538
3539 @c man end
3540
3541 @c man begin OPTIONS nlmconv
3542
3543 @table @env
3544 @item -I @var{bfdname}
3545 @itemx --input-target=@var{bfdname}
3546 Object format of the input file. @command{nlmconv} can usually determine
3547 the format of a given file (so no default is necessary).
3548 @xref{Target Selection}, for more information.
3549
3550 @item -O @var{bfdname}
3551 @itemx --output-target=@var{bfdname}
3552 Object format of the output file. @command{nlmconv} infers the output
3553 format based on the input format, e.g. for a @samp{i386} input file the
3554 output format is @samp{nlm32-i386}.
3555 @xref{Target Selection}, for more information.
3556
3557 @item -T @var{headerfile}
3558 @itemx --header-file=@var{headerfile}
3559 Reads @var{headerfile} for NLM header information. For instructions on
3560 writing the NLM command file language used in header files, see@ see the
3561 @samp{linkers} section, of the @cite{NLM Development and Tools
3562 Overview}, which is part of the NLM Software Developer's Kit, available
3563 from Novell, Inc.
3564
3565 @item -d
3566 @itemx --debug
3567 Displays (on standard error) the linker command line used by @command{nlmconv}.
3568
3569 @item -l @var{linker}
3570 @itemx --linker=@var{linker}
3571 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3572 relative pathname.
3573
3574 @item -h
3575 @itemx --help
3576 Prints a usage summary.
3577
3578 @item -V
3579 @itemx --version
3580 Prints the version number for @command{nlmconv}.
3581 @end table
3582
3583 @c man end
3584
3585 @ignore
3586 @c man begin SEEALSO nlmconv
3587 the Info entries for @file{binutils}.
3588 @c man end
3589 @end ignore
3590
3591 @node windmc
3592 @chapter windmc
3593
3594 @command{windmc} may be used to generator Windows message resources.
3595
3596 @quotation
3597 @emph{Warning:} @command{windmc} is not always built as part of the binary
3598 utilities, since it is only useful for Windows targets.
3599 @end quotation
3600
3601 @c man title windmc generates Windows message resources.
3602
3603 @smallexample
3604 @c man begin SYNOPSIS windmc
3605 windmc [options] input-file
3606 @c man end
3607 @end smallexample
3608
3609 @c man begin DESCRIPTION windmc
3610
3611 @command{windmc} reads message definitions from an input file (.mc) and
3612 translate them into a set of output files. The output files may be of
3613 four kinds:
3614
3615 @table @code
3616 @item h
3617 A C header file containing the message definitions.
3618
3619 @item rc
3620 A resource file compilable by the @command{windres} tool.
3621
3622 @item bin
3623 One or more binary files containing the resource data for a specific
3624 message language.
3625
3626 @item dbg
3627 A C include file that maps message id's to their symbolic name.
3628 @end table
3629
3630 The exact description of these different formats is available in
3631 documentation from Microsoft.
3632
3633 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3634 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3635 Windows Message Compiler.
3636
3637 @c man end
3638
3639 @c man begin OPTIONS windmc
3640
3641 @table @env
3642 @item -a
3643 @itemx --ascii_in
3644 Specifies that the input file specified is ASCII. This is the default
3645 behaviour.
3646
3647 @item -A
3648 @itemx --ascii_out
3649 Specifies that messages in the output @code{bin} files should be in ASCII
3650 format.
3651
3652 @item -b
3653 @itemx --binprefix
3654 Specifies that @code{bin} filenames should have to be prefixed by the
3655 basename of the source file.
3656
3657 @item -c
3658 @itemx --customflag
3659 Sets the customer bit in all message id's.
3660
3661 @item -C @var{codepage}
3662 @itemx --codepage_in @var{codepage}
3663 Sets the default codepage to be used to convert input file to UTF16. The
3664 default is ocdepage 1252.
3665
3666 @item -d
3667 @itemx --decimal_values
3668 Outputs the constants in the header file in decimal. Default is using
3669 hexadecimal output.
3670
3671 @item -e @var{ext}
3672 @itemx --extension @var{ext}
3673 The extension for the header file. The default is .h extension.
3674
3675 @item -F @var{target}
3676 @itemx --target @var{target}
3677 Specify the BFD format to use for a bin file as output. This
3678 is a BFD target name; you can use the @option{--help} option to see a list
3679 of supported targets. Normally @command{windmc} will use the default
3680 format, which is the first one listed by the @option{--help} option.
3681 @ifclear man
3682 @ref{Target Selection}.
3683 @end ifclear
3684
3685 @item -h @var{path}
3686 @itemx --headerdir @var{path}
3687 The target directory of the generated header file. The default is the
3688 current directory.
3689
3690 @item -H
3691 @itemx --help
3692 Displays a list of command line options and then exits.
3693
3694 @item -m @var{characters}
3695 @itemx --maxlength @var{characters}
3696 Instructs @command{windmc} to generate a warning if the length
3697 of any message exceeds the number specified.
3698
3699 @item -n
3700 @itemx --nullterminate
3701 Terminate message text in @code{bin} files by zero. By default they are
3702 terminated by CR/LF.
3703
3704 @item -o
3705 @itemx --hresult_use
3706 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3707 file, using HRESULT definitions. Status codes are used if the flag is not
3708 specified.
3709
3710 @item -O @var{codepage}
3711 @itemx --codepage_out @var{codepage}
3712 Sets the default codepage to be used to output text files. The default
3713 is ocdepage 1252.
3714
3715 @item -r @var{path}
3716 @itemx --rcdir @var{path}
3717 The target directory for the generated @code{rc} script and the generated
3718 @code{bin} files that the resource compiler script includes. The default
3719 is the current directory.
3720
3721 @item -u
3722 @itemx --unicode_in
3723 Specifies that the input file is UTF16.
3724
3725 @item -U
3726 @itemx --unicode_out
3727 Specifies that messages in the output @code{bin} file should be in UTF16
3728 format. This is the default behaviour.
3729
3730 @item -v
3731 @item --verbose
3732 Enable verbose mode.
3733
3734 @item -V
3735 @item --version
3736 Prints the version number for @command{windmc}.
3737
3738 @item -x @var{path}
3739 @itemx --xdgb @var{path}
3740 The path of the @code{dbg} C include file that maps message id's to the
3741 symbolic name. No such file is generated without specifying the switch.
3742 @end table
3743
3744 @c man end
3745
3746 @ignore
3747 @c man begin SEEALSO windmc
3748 the Info entries for @file{binutils}.
3749 @c man end
3750 @end ignore
3751
3752 @node windres
3753 @chapter windres
3754
3755 @command{windres} may be used to manipulate Windows resources.
3756
3757 @quotation
3758 @emph{Warning:} @command{windres} is not always built as part of the binary
3759 utilities, since it is only useful for Windows targets.
3760 @end quotation
3761
3762 @c man title windres manipulate Windows resources.
3763
3764 @smallexample
3765 @c man begin SYNOPSIS windres
3766 windres [options] [input-file] [output-file]
3767 @c man end
3768 @end smallexample
3769
3770 @c man begin DESCRIPTION windres
3771
3772 @command{windres} reads resources from an input file and copies them into
3773 an output file. Either file may be in one of three formats:
3774
3775 @table @code
3776 @item rc
3777 A text format read by the Resource Compiler.
3778
3779 @item res
3780 A binary format generated by the Resource Compiler.
3781
3782 @item coff
3783 A COFF object or executable.
3784 @end table
3785
3786 The exact description of these different formats is available in
3787 documentation from Microsoft.
3788
3789 When @command{windres} converts from the @code{rc} format to the @code{res}
3790 format, it is acting like the Windows Resource Compiler. When
3791 @command{windres} converts from the @code{res} format to the @code{coff}
3792 format, it is acting like the Windows @code{CVTRES} program.
3793
3794 When @command{windres} generates an @code{rc} file, the output is similar
3795 but not identical to the format expected for the input. When an input
3796 @code{rc} file refers to an external filename, an output @code{rc} file
3797 will instead include the file contents.
3798
3799 If the input or output format is not specified, @command{windres} will
3800 guess based on the file name, or, for the input file, the file contents.
3801 A file with an extension of @file{.rc} will be treated as an @code{rc}
3802 file, a file with an extension of @file{.res} will be treated as a
3803 @code{res} file, and a file with an extension of @file{.o} or
3804 @file{.exe} will be treated as a @code{coff} file.
3805
3806 If no output file is specified, @command{windres} will print the resources
3807 in @code{rc} format to standard output.
3808
3809 The normal use is for you to write an @code{rc} file, use @command{windres}
3810 to convert it to a COFF object file, and then link the COFF file into
3811 your application. This will make the resources described in the
3812 @code{rc} file available to Windows.
3813
3814 @c man end
3815
3816 @c man begin OPTIONS windres
3817
3818 @table @env
3819 @item -i @var{filename}
3820 @itemx --input @var{filename}
3821 The name of the input file. If this option is not used, then
3822 @command{windres} will use the first non-option argument as the input file
3823 name. If there are no non-option arguments, then @command{windres} will
3824 read from standard input. @command{windres} can not read a COFF file from
3825 standard input.
3826
3827 @item -o @var{filename}
3828 @itemx --output @var{filename}
3829 The name of the output file. If this option is not used, then
3830 @command{windres} will use the first non-option argument, after any used
3831 for the input file name, as the output file name. If there is no
3832 non-option argument, then @command{windres} will write to standard output.
3833 @command{windres} can not write a COFF file to standard output. Note,
3834 for compatibility with @command{rc} the option @option{-fo} is also
3835 accepted, but its use is not recommended.
3836
3837 @item -J @var{format}
3838 @itemx --input-format @var{format}
3839 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3840 @samp{coff}. If no input format is specified, @command{windres} will
3841 guess, as described above.
3842
3843 @item -O @var{format}
3844 @itemx --output-format @var{format}
3845 The output format to generate. @var{format} may be @samp{res},
3846 @samp{rc}, or @samp{coff}. If no output format is specified,
3847 @command{windres} will guess, as described above.
3848
3849 @item -F @var{target}
3850 @itemx --target @var{target}
3851 Specify the BFD format to use for a COFF file as input or output. This
3852 is a BFD target name; you can use the @option{--help} option to see a list
3853 of supported targets. Normally @command{windres} will use the default
3854 format, which is the first one listed by the @option{--help} option.
3855 @ifclear man
3856 @ref{Target Selection}.
3857 @end ifclear
3858
3859 @item --preprocessor @var{program}
3860 When @command{windres} reads an @code{rc} file, it runs it through the C
3861 preprocessor first. This option may be used to specify the preprocessor
3862 to use, including any leading arguments. The default preprocessor
3863 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3864
3865 @item --preprocessor-arg @var{option}
3866 When @command{windres} reads an @code{rc} file, it runs it through
3867 the C preprocessor first. This option may be used to specify additional
3868 text to be passed to preprocessor on its command line.
3869 This option can be used multiple times to add multiple options to the
3870 preprocessor command line.
3871
3872 @item -I @var{directory}
3873 @itemx --include-dir @var{directory}
3874 Specify an include directory to use when reading an @code{rc} file.
3875 @command{windres} will pass this to the preprocessor as an @option{-I}
3876 option. @command{windres} will also search this directory when looking for
3877 files named in the @code{rc} file. If the argument passed to this command
3878 matches any of the supported @var{formats} (as described in the @option{-J}
3879 option), it will issue a deprecation warning, and behave just like the
3880 @option{-J} option. New programs should not use this behaviour. If a
3881 directory happens to match a @var{format}, simple prefix it with @samp{./}
3882 to disable the backward compatibility.
3883
3884 @item -D @var{target}
3885 @itemx --define @var{sym}[=@var{val}]
3886 Specify a @option{-D} option to pass to the preprocessor when reading an
3887 @code{rc} file.
3888
3889 @item -U @var{target}
3890 @itemx --undefine @var{sym}
3891 Specify a @option{-U} option to pass to the preprocessor when reading an
3892 @code{rc} file.
3893
3894 @item -r
3895 Ignored for compatibility with rc.
3896
3897 @item -v
3898 Enable verbose mode. This tells you what the preprocessor is if you
3899 didn't specify one.
3900
3901 @item -c @var{val}
3902 @item --codepage @var{val}
3903 Specify the default codepage to use when reading an @code{rc} file.
3904 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3905 codepage code. The valid range is from zero up to 0xffff, but the
3906 validity of the codepage is host and configuration dependent.
3907
3908 @item -l @var{val}
3909 @item --language @var{val}
3910 Specify the default language to use when reading an @code{rc} file.
3911 @var{val} should be a hexadecimal language code. The low eight bits are
3912 the language, and the high eight bits are the sublanguage.
3913
3914 @item --use-temp-file
3915 Use a temporary file to instead of using popen to read the output of
3916 the preprocessor. Use this option if the popen implementation is buggy
3917 on the host (eg., certain non-English language versions of Windows 95 and
3918 Windows 98 are known to have buggy popen where the output will instead
3919 go the console).
3920
3921 @item --no-use-temp-file
3922 Use popen, not a temporary file, to read the output of the preprocessor.
3923 This is the default behaviour.
3924
3925 @item -h
3926 @item --help
3927 Prints a usage summary.
3928
3929 @item -V
3930 @item --version
3931 Prints the version number for @command{windres}.
3932
3933 @item --yydebug
3934 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3935 this will turn on parser debugging.
3936 @end table
3937
3938 @c man end
3939
3940 @ignore
3941 @c man begin SEEALSO windres
3942 the Info entries for @file{binutils}.
3943 @c man end
3944 @end ignore
3945
3946 @node dlltool
3947 @chapter dlltool
3948 @cindex DLL
3949 @kindex dlltool
3950
3951 @command{dlltool} is used to create the files needed to create dynamic
3952 link libraries (DLLs) on systems which understand PE format image
3953 files such as Windows. A DLL contains an export table which contains
3954 information that the runtime loader needs to resolve references from a
3955 referencing program.
3956
3957 The export table is generated by this program by reading in a
3958 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3959 will be in the DLL. A @file{.o} file can contain information in
3960 special @samp{.drectve} sections with export information.
3961
3962 @quotation
3963 @emph{Note:} @command{dlltool} is not always built as part of the
3964 binary utilities, since it is only useful for those targets which
3965 support DLLs.
3966 @end quotation
3967
3968 @c man title dlltool Create files needed to build and use DLLs.
3969
3970 @smallexample
3971 @c man begin SYNOPSIS dlltool
3972 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3973 [@option{-b}|@option{--base-file} @var{base-file-name}]
3974 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3975 [@option{-z}|@option{--output-def} @var{def-file-name}]
3976 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3977 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
3978 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3979 [@option{--exclude-symbols} @var{list}]
3980 [@option{--no-default-excludes}]
3981 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3982 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3983 [@option{-a}|@option{--add-indirect}]
3984 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3985 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3986 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3987 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
3988 [@option{--use-nul-prefixed-import-tables}]
3989 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
3990 [@option{-i}|@option{--interwork}]
3991 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3992 [@option{-v}|@option{--verbose}]
3993 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3994 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
3995 [object-file @dots{}]
3996 @c man end
3997 @end smallexample
3998
3999 @c man begin DESCRIPTION dlltool
4000
4001 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4002 @option{-b} options as well as object files specified on the command
4003 line. It then processes these inputs and if the @option{-e} option has
4004 been specified it creates a exports file. If the @option{-l} option
4005 has been specified it creates a library file and if the @option{-z} option
4006 has been specified it creates a def file. Any or all of the @option{-e},
4007 @option{-l} and @option{-z} options can be present in one invocation of
4008 dlltool.
4009
4010 When creating a DLL, along with the source for the DLL, it is necessary
4011 to have three other files. @command{dlltool} can help with the creation of
4012 these files.
4013
4014 The first file is a @file{.def} file which specifies which functions are
4015 exported from the DLL, which functions the DLL imports, and so on. This
4016 is a text file and can be created by hand, or @command{dlltool} can be used
4017 to create it using the @option{-z} option. In this case @command{dlltool}
4018 will scan the object files specified on its command line looking for
4019 those functions which have been specially marked as being exported and
4020 put entries for them in the @file{.def} file it creates.
4021
4022 In order to mark a function as being exported from a DLL, it needs to
4023 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4024 section of the object file. This can be done in C by using the
4025 asm() operator:
4026
4027 @smallexample
4028 asm (".section .drectve");
4029 asm (".ascii \"-export:my_func\"");
4030
4031 int my_func (void) @{ @dots{} @}
4032 @end smallexample
4033
4034 The second file needed for DLL creation is an exports file. This file
4035 is linked with the object files that make up the body of the DLL and it
4036 handles the interface between the DLL and the outside world. This is a
4037 binary file and it can be created by giving the @option{-e} option to
4038 @command{dlltool} when it is creating or reading in a @file{.def} file.
4039
4040 The third file needed for DLL creation is the library file that programs
4041 will link with in order to access the functions in the DLL (an `import
4042 library'). This file can be created by giving the @option{-l} option to
4043 dlltool when it is creating or reading in a @file{.def} file.
4044
4045 If the @option{-y} option is specified, dlltool generates a delay-import
4046 library that can be used instead of the normal import library to allow
4047 a program to link to the dll only as soon as an imported function is
4048 called for the first time. The resulting executable will need to be
4049 linked to the static delayimp library containing __delayLoadHelper2(),
4050 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4051
4052 @command{dlltool} builds the library file by hand, but it builds the
4053 exports file by creating temporary files containing assembler statements
4054 and then assembling these. The @option{-S} command line option can be
4055 used to specify the path to the assembler that dlltool will use,
4056 and the @option{-f} option can be used to pass specific flags to that
4057 assembler. The @option{-n} can be used to prevent dlltool from deleting
4058 these temporary assembler files when it is done, and if @option{-n} is
4059 specified twice then this will prevent dlltool from deleting the
4060 temporary object files it used to build the library.
4061
4062 Here is an example of creating a DLL from a source file @samp{dll.c} and
4063 also creating a program (from an object file called @samp{program.o})
4064 that uses that DLL:
4065
4066 @smallexample
4067 gcc -c dll.c
4068 dlltool -e exports.o -l dll.lib dll.o
4069 gcc dll.o exports.o -o dll.dll
4070 gcc program.o dll.lib -o program
4071 @end smallexample
4072
4073
4074 @command{dlltool} may also be used to query an existing import library
4075 to determine the name of the DLL to which it is associated. See the
4076 description of the @option{-I} or @option{--identify} option.
4077
4078 @c man end
4079
4080 @c man begin OPTIONS dlltool
4081
4082 The command line options have the following meanings:
4083
4084 @table @env
4085
4086 @item -d @var{filename}
4087 @itemx --input-def @var{filename}
4088 @cindex input .def file
4089 Specifies the name of a @file{.def} file to be read in and processed.
4090
4091 @item -b @var{filename}
4092 @itemx --base-file @var{filename}
4093 @cindex base files
4094 Specifies the name of a base file to be read in and processed. The
4095 contents of this file will be added to the relocation section in the
4096 exports file generated by dlltool.
4097
4098 @item -e @var{filename}
4099 @itemx --output-exp @var{filename}
4100 Specifies the name of the export file to be created by dlltool.
4101
4102 @item -z @var{filename}
4103 @itemx --output-def @var{filename}
4104 Specifies the name of the @file{.def} file to be created by dlltool.
4105
4106 @item -l @var{filename}
4107 @itemx --output-lib @var{filename}
4108 Specifies the name of the library file to be created by dlltool.
4109
4110 @item -y @var{filename}
4111 @itemx --output-delaylib @var{filename}
4112 Specifies the name of the delay-import library file to be created by dlltool.
4113
4114 @item --export-all-symbols
4115 Treat all global and weak defined symbols found in the input object
4116 files as symbols to be exported. There is a small list of symbols which
4117 are not exported by default; see the @option{--no-default-excludes}
4118 option. You may add to the list of symbols to not export by using the
4119 @option{--exclude-symbols} option.
4120
4121 @item --no-export-all-symbols
4122 Only export symbols explicitly listed in an input @file{.def} file or in
4123 @samp{.drectve} sections in the input object files. This is the default
4124 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4125 attributes in the source code.
4126
4127 @item --exclude-symbols @var{list}
4128 Do not export the symbols in @var{list}. This is a list of symbol names
4129 separated by comma or colon characters. The symbol names should not
4130 contain a leading underscore. This is only meaningful when
4131 @option{--export-all-symbols} is used.
4132
4133 @item --no-default-excludes
4134 When @option{--export-all-symbols} is used, it will by default avoid
4135 exporting certain special symbols. The current list of symbols to avoid
4136 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4137 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4138 to go ahead and export these special symbols. This is only meaningful
4139 when @option{--export-all-symbols} is used.
4140
4141 @item -S @var{path}
4142 @itemx --as @var{path}
4143 Specifies the path, including the filename, of the assembler to be used
4144 to create the exports file.
4145
4146 @item -f @var{options}
4147 @itemx --as-flags @var{options}
4148 Specifies any specific command line options to be passed to the
4149 assembler when building the exports file. This option will work even if
4150 the @option{-S} option is not used. This option only takes one argument,
4151 and if it occurs more than once on the command line, then later
4152 occurrences will override earlier occurrences. So if it is necessary to
4153 pass multiple options to the assembler they should be enclosed in
4154 double quotes.
4155
4156 @item -D @var{name}
4157 @itemx --dll-name @var{name}
4158 Specifies the name to be stored in the @file{.def} file as the name of
4159 the DLL when the @option{-e} option is used. If this option is not
4160 present, then the filename given to the @option{-e} option will be
4161 used as the name of the DLL.
4162
4163 @item -m @var{machine}
4164 @itemx -machine @var{machine}
4165 Specifies the type of machine for which the library file should be
4166 built. @command{dlltool} has a built in default type, depending upon how
4167 it was created, but this option can be used to override that. This is
4168 normally only useful when creating DLLs for an ARM processor, when the
4169 contents of the DLL are actually encode using Thumb instructions.
4170
4171 @item -a
4172 @itemx --add-indirect
4173 Specifies that when @command{dlltool} is creating the exports file it
4174 should add a section which allows the exported functions to be
4175 referenced without using the import library. Whatever the hell that
4176 means!
4177
4178 @item -U
4179 @itemx --add-underscore
4180 Specifies that when @command{dlltool} is creating the exports file it
4181 should prepend an underscore to the names of @emph{all} exported symbols.
4182
4183 @item --no-leading-underscore
4184 @item --leading-underscore
4185 Specifies whether standard symbol should be forced to be prefixed, or
4186 not.
4187
4188 @item --add-stdcall-underscore
4189 Specifies that when @command{dlltool} is creating the exports file it
4190 should prepend an underscore to the names of exported @emph{stdcall}
4191 functions. Variable names and non-stdcall function names are not modified.
4192 This option is useful when creating GNU-compatible import libs for third
4193 party DLLs that were built with MS-Windows tools.
4194
4195 @item -k
4196 @itemx --kill-at
4197 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4198 of stdcall functions that will be imported from the DLL. This is
4199 useful when creating an import library for a DLL which exports stdcall
4200 functions but without the usual @samp{@@<number>} symbol name suffix.
4201
4202 This does not change the naming of symbols provided by the import library
4203 to programs linked against it, but only the entries in the import table
4204 (ie the .idata section).
4205
4206 @item -A
4207 @itemx --add-stdcall-alias
4208 Specifies that when @command{dlltool} is creating the exports file it
4209 should add aliases for stdcall symbols without @samp{@@ <number>}
4210 in addition to the symbols with @samp{@@ <number>}.
4211
4212 @item -p
4213 @itemx --ext-prefix-alias @var{prefix}
4214 Causes @command{dlltool} to create external aliases for all DLL
4215 imports with the specified prefix. The aliases are created for both
4216 external and import symbols with no leading underscore.
4217
4218 @item -x
4219 @itemx --no-idata4
4220 Specifies that when @command{dlltool} is creating the exports and library
4221 files it should omit the @code{.idata4} section. This is for compatibility
4222 with certain operating systems.
4223
4224 @item --use-nul-prefixed-import-tables
4225 Specifies that when @command{dlltool} is creating the exports and library
4226 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4227 element. This emulates old gnu import library generation of
4228 @code{dlltool}. By default this option is turned off.
4229
4230 @item -c
4231 @itemx --no-idata5
4232 Specifies that when @command{dlltool} is creating the exports and library
4233 files it should omit the @code{.idata5} section. This is for compatibility
4234 with certain operating systems.
4235
4236 @item -I @var{filename}
4237 @itemx --identify @var{filename}
4238 Specifies that @command{dlltool} should inspect the import library
4239 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4240 of the associated DLL(s). This can be performed in addition to any
4241 other operations indicated by the other options and arguments.
4242 @command{dlltool} fails if the import library does not exist or is not
4243 actually an import library. See also @option{--identify-strict}.
4244
4245 @item --identify-strict
4246 Modifies the behavior of the @option{--identify} option, such
4247 that an error is reported if @var{filename} is associated with
4248 more than one DLL.
4249
4250 @item -i
4251 @itemx --interwork
4252 Specifies that @command{dlltool} should mark the objects in the library
4253 file and exports file that it produces as supporting interworking
4254 between ARM and Thumb code.
4255
4256 @item -n
4257 @itemx --nodelete
4258 Makes @command{dlltool} preserve the temporary assembler files it used to
4259 create the exports file. If this option is repeated then dlltool will
4260 also preserve the temporary object files it uses to create the library
4261 file.
4262
4263 @item -t @var{prefix}
4264 @itemx --temp-prefix @var{prefix}
4265 Makes @command{dlltool} use @var{prefix} when constructing the names of
4266 temporary assembler and object files. By default, the temp file prefix
4267 is generated from the pid.
4268
4269 @item -v
4270 @itemx --verbose
4271 Make dlltool describe what it is doing.
4272
4273 @item -h
4274 @itemx --help
4275 Displays a list of command line options and then exits.
4276
4277 @item -V
4278 @itemx --version
4279 Displays dlltool's version number and then exits.
4280
4281 @end table
4282
4283 @c man end
4284
4285 @menu
4286 * def file format:: The format of the dlltool @file{.def} file
4287 @end menu
4288
4289 @node def file format
4290 @section The format of the @command{dlltool} @file{.def} file
4291
4292 A @file{.def} file contains any number of the following commands:
4293
4294 @table @asis
4295
4296 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4297 The result is going to be named @var{name}@code{.exe}.
4298
4299 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4300 The result is going to be named @var{name}@code{.dll}.
4301 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4302 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4303 details).
4304
4305 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4306 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4307 Declares @var{name1} as an exported symbol from the DLL, with optional
4308 ordinal number @var{integer}, or declares @var{name1} as an alias
4309 (forward) of the function @var{external-name} in the DLL.
4310 If @var{its_name} is specified, this name is used as string in export table.
4311 @var{module-name}.
4312 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4313 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4314 If you want to use LIBRARY as name then you need to quote it.
4315
4316 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) [ == ) @var{its_name} @code{]} *}
4317 Declares that @var{external-name} or the exported function whose
4318 ordinal number is @var{integer} is to be imported from the file
4319 @var{module-name}. If @var{internal-name} is specified then this is
4320 the name that the imported function will be referred to in the body of
4321 the DLL.
4322 If @var{its_name} is specified, this name is used as string in import table.
4323 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4324 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4325 If you want to use LIBRARY as name then you need to quote it.
4326
4327 @item @code{DESCRIPTION} @var{string}
4328 Puts @var{string} into the output @file{.exp} file in the
4329 @code{.rdata} section.
4330
4331 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4332 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4333 Generates @code{--stack} or @code{--heap}
4334 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4335 section. The linker will see this and act upon it.
4336
4337 @item @code{CODE} @var{attr} @code{+}
4338 @item @code{DATA} @var{attr} @code{+}
4339 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4340 Generates @code{--attr} @var{section-name} @var{attr} in the output
4341 @code{.drectve} section, where @var{attr} is one of @code{READ},
4342 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4343 this and act upon it.
4344
4345 @end table
4346
4347 @ignore
4348 @c man begin SEEALSO dlltool
4349 The Info pages for @file{binutils}.
4350 @c man end
4351 @end ignore
4352
4353 @node readelf
4354 @chapter readelf
4355
4356 @cindex ELF file information
4357 @kindex readelf
4358
4359 @c man title readelf Displays information about ELF files.
4360
4361 @smallexample
4362 @c man begin SYNOPSIS readelf
4363 readelf [@option{-a}|@option{--all}]
4364 [@option{-h}|@option{--file-header}]
4365 [@option{-l}|@option{--program-headers}|@option{--segments}]
4366 [@option{-S}|@option{--section-headers}|@option{--sections}]
4367 [@option{-g}|@option{--section-groups}]
4368 [@option{-t}|@option{--section-details}]
4369 [@option{-e}|@option{--headers}]
4370 [@option{-s}|@option{--syms}|@option{--symbols}]
4371 [@option{--dyn-syms}]
4372 [@option{-n}|@option{--notes}]
4373 [@option{-r}|@option{--relocs}]
4374 [@option{-u}|@option{--unwind}]
4375 [@option{-d}|@option{--dynamic}]
4376 [@option{-V}|@option{--version-info}]
4377 [@option{-A}|@option{--arch-specific}]
4378 [@option{-D}|@option{--use-dynamic}]
4379 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4380 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4381 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4382 [@option{-z}|@option{--decompress}]
4383 [@option{-c}|@option{--archive-index}]
4384 [@option{-w[lLiaprmfFsoRt]}|
4385 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
4386 [@option{--dwarf-depth=@var{n}}]
4387 [@option{--dwarf-start=@var{n}}]
4388 [@option{-I}|@option{--histogram}]
4389 [@option{-v}|@option{--version}]
4390 [@option{-W}|@option{--wide}]
4391 [@option{-H}|@option{--help}]
4392 @var{elffile}@dots{}
4393 @c man end
4394 @end smallexample
4395
4396 @c man begin DESCRIPTION readelf
4397
4398 @command{readelf} displays information about one or more ELF format object
4399 files. The options control what particular information to display.
4400
4401 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4402 64-bit ELF files are supported, as are archives containing ELF files.
4403
4404 This program performs a similar function to @command{objdump} but it
4405 goes into more detail and it exists independently of the @sc{bfd}
4406 library, so if there is a bug in @sc{bfd} then readelf will not be
4407 affected.
4408
4409 @c man end
4410
4411 @c man begin OPTIONS readelf
4412
4413 The long and short forms of options, shown here as alternatives, are
4414 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4415 given.
4416
4417 @table @env
4418 @item -a
4419 @itemx --all
4420 Equivalent to specifying @option{--file-header},
4421 @option{--program-headers}, @option{--sections}, @option{--symbols},
4422 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4423 @option{--version-info}.
4424
4425 @item -h
4426 @itemx --file-header
4427 @cindex ELF file header information
4428 Displays the information contained in the ELF header at the start of the
4429 file.
4430
4431 @item -l
4432 @itemx --program-headers
4433 @itemx --segments
4434 @cindex ELF program header information
4435 @cindex ELF segment information
4436 Displays the information contained in the file's segment headers, if it
4437 has any.
4438
4439 @item -S
4440 @itemx --sections
4441 @itemx --section-headers
4442 @cindex ELF section information
4443 Displays the information contained in the file's section headers, if it
4444 has any.
4445
4446 @item -g
4447 @itemx --section-groups
4448 @cindex ELF section group information
4449 Displays the information contained in the file's section groups, if it
4450 has any.
4451
4452 @item -t
4453 @itemx --section-details
4454 @cindex ELF section information
4455 Displays the detailed section information. Implies @option{-S}.
4456
4457 @item -s
4458 @itemx --symbols
4459 @itemx --syms
4460 @cindex ELF symbol table information
4461 Displays the entries in symbol table section of the file, if it has one.
4462
4463 @item --dyn-syms
4464 @cindex ELF dynamic symbol table information
4465 Displays the entries in dynamic symbol table section of the file, if it
4466 has one.
4467
4468 @item -e
4469 @itemx --headers
4470 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4471
4472 @item -n
4473 @itemx --notes
4474 @cindex ELF notes
4475 Displays the contents of the NOTE segments and/or sections, if any.
4476
4477 @item -r
4478 @itemx --relocs
4479 @cindex ELF reloc information
4480 Displays the contents of the file's relocation section, if it has one.
4481
4482 @item -u
4483 @itemx --unwind
4484 @cindex unwind information
4485 Displays the contents of the file's unwind section, if it has one. Only
4486 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4487 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4488
4489 @item -d
4490 @itemx --dynamic
4491 @cindex ELF dynamic section information
4492 Displays the contents of the file's dynamic section, if it has one.
4493
4494 @item -V
4495 @itemx --version-info
4496 @cindex ELF version sections information
4497 Displays the contents of the version sections in the file, it they
4498 exist.
4499
4500 @item -A
4501 @itemx --arch-specific
4502 Displays architecture-specific information in the file, if there
4503 is any.
4504
4505 @item -D
4506 @itemx --use-dynamic
4507 When displaying symbols, this option makes @command{readelf} use the
4508 symbol hash tables in the file's dynamic section, rather than the
4509 symbol table sections.
4510
4511 @item -x <number or name>
4512 @itemx --hex-dump=<number or name>
4513 Displays the contents of the indicated section as a hexadecimal bytes.
4514 A number identifies a particular section by index in the section table;
4515 any other string identifies all sections with that name in the object file.
4516
4517 @item -R <number or name>
4518 @itemx --relocated-dump=<number or name>
4519 Displays the contents of the indicated section as a hexadecimal
4520 bytes. A number identifies a particular section by index in the
4521 section table; any other string identifies all sections with that name
4522 in the object file. The contents of the section will be relocated
4523 before they are displayed.
4524
4525 @item -p <number or name>
4526 @itemx --string-dump=<number or name>
4527 Displays the contents of the indicated section as printable strings.
4528 A number identifies a particular section by index in the section table;
4529 any other string identifies all sections with that name in the object file.
4530
4531 @item -z
4532 @itemx --decompress
4533 Requests that the section(s) being dumped by @option{x}, @option{R} or
4534 @option{p} options are decompressed before being displayed. If the
4535 section(s) are not compressed then they are displayed as is.
4536
4537 @item -c
4538 @itemx --archive-index
4539 @cindex Archive file symbol index information
4540 Displays the file symbol index information contained in the header part
4541 of binary archives. Performs the same function as the @option{t}
4542 command to @command{ar}, but without using the BFD library. @xref{ar}.
4543
4544 @item -w[lLiaprmfFsoRt]
4545 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
4546 Displays the contents of the debug sections in the file, if any are
4547 present. If one of the optional letters or words follows the switch
4548 then only data found in those specific sections will be dumped.
4549
4550 Note that there is no single letter option to display the content of
4551 trace sections or .gdb_index.
4552
4553 Note: the @option{=decodedline} option will display the interpreted
4554 contents of a .debug_line section whereas the @option{=rawline} option
4555 dumps the contents in a raw format.
4556
4557 Note: the @option{=frames-interp} option will display the interpreted
4558 contents of a .debug_frame section whereas the @option{=frames} option
4559 dumps the contents in a raw format.
4560
4561 Note: the output from the @option{=info} option can also be affected
4562 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4563
4564 @item --dwarf-depth=@var{n}
4565 Limit the dump of the @code{.debug_info} section to @var{n} children.
4566 This is only useful with @option{--debug-dump=info}. The default is
4567 to print all DIEs; the special value 0 for @var{n} will also have this
4568 effect.
4569
4570 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4571 levels will not be printed. The range for @var{n} is zero-based.
4572
4573 @item --dwarf-start=@var{n}
4574 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4575 useful with @option{--debug-dump=info}.
4576
4577 If specified, this option will suppress printing of any header
4578 information and all DIEs before the DIE numbered @var{n}. Only
4579 siblings and children of the specified DIE will be printed.
4580
4581 This can be used in conjunction with @option{--dwarf-depth}.
4582
4583 @item -I
4584 @itemx --histogram
4585 Display a histogram of bucket list lengths when displaying the contents
4586 of the symbol tables.
4587
4588 @item -v
4589 @itemx --version
4590 Display the version number of readelf.
4591
4592 @item -W
4593 @itemx --wide
4594 Don't break output lines to fit into 80 columns. By default
4595 @command{readelf} breaks section header and segment listing lines for
4596 64-bit ELF files, so that they fit into 80 columns. This option causes
4597 @command{readelf} to print each section header resp. each segment one a
4598 single line, which is far more readable on terminals wider than 80 columns.
4599
4600 @item -H
4601 @itemx --help
4602 Display the command line options understood by @command{readelf}.
4603
4604 @end table
4605
4606 @c man end
4607
4608 @ignore
4609 @c man begin SEEALSO readelf
4610 objdump(1), and the Info entries for @file{binutils}.
4611 @c man end
4612 @end ignore
4613
4614 @node elfedit
4615 @chapter elfedit
4616
4617 @cindex Update ELF header
4618 @kindex elfedit
4619
4620 @c man title elfedit Update the ELF header of ELF files.
4621
4622 @smallexample
4623 @c man begin SYNOPSIS elfedit
4624 elfedit [@option{--input-mach=}@var{machine}]
4625 [@option{--input-type=}@var{type}]
4626 [@option{--input-osabi=}@var{osabi}]
4627 @option{--output-mach=}@var{machine}
4628 @option{--output-type=}@var{type}
4629 @option{--output-osabi=}@var{osabi}
4630 [@option{-v}|@option{--version}]
4631 [@option{-h}|@option{--help}]
4632 @var{elffile}@dots{}
4633 @c man end
4634 @end smallexample
4635
4636 @c man begin DESCRIPTION elfedit
4637
4638 @command{elfedit} updates the ELF header of ELF files which have
4639 the matching ELF machine and file types. The options control how and
4640 which fields in the ELF header should be updated.
4641
4642 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4643 64-bit ELF files are supported, as are archives containing ELF files.
4644 @c man end
4645
4646 @c man begin OPTIONS elfedit
4647
4648 The long and short forms of options, shown here as alternatives, are
4649 equivalent. At least one of the @option{--output-mach},
4650 @option{--output-type} and @option{--output-osabi} options must be given.
4651
4652 @table @env
4653
4654 @item --input-mach=@var{machine}
4655 Set the matching input ELF machine type to @var{machine}. If
4656 @option{--input-mach} isn't specified, it will match any ELF
4657 machine types.
4658
4659 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4660 @var{K1OM} and @var{x86-64}.
4661
4662 @item --output-mach=@var{machine}
4663 Change the ELF machine type in the ELF header to @var{machine}. The
4664 supported ELF machine types are the same as @option{--input-mach}.
4665
4666 @item --input-type=@var{type}
4667 Set the matching input ELF file type to @var{type}. If
4668 @option{--input-type} isn't specified, it will match any ELF file types.
4669
4670 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4671
4672 @item --output-type=@var{type}
4673 Change the ELF file type in the ELF header to @var{type}. The
4674 supported ELF types are the same as @option{--input-type}.
4675
4676 @item --input-osabi=@var{osabi}
4677 Set the matching input ELF file OSABI to @var{osabi}. If
4678 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4679
4680 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4681 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4682 @var{Solaris}, @var{AIX}, @var{Irix},
4683 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4684 @var{NSK}, @var{AROS} and @var{FenixOS}.
4685
4686 @item --output-osabi=@var{osabi}
4687 Change the ELF OSABI in the ELF header to @var{osabi}. The
4688 supported ELF OSABI are the same as @option{--input-osabi}.
4689
4690 @item -v
4691 @itemx --version
4692 Display the version number of @command{elfedit}.
4693
4694 @item -h
4695 @itemx --help
4696 Display the command line options understood by @command{elfedit}.
4697
4698 @end table
4699
4700 @c man end
4701
4702 @ignore
4703 @c man begin SEEALSO elfedit
4704 readelf(1), and the Info entries for @file{binutils}.
4705 @c man end
4706 @end ignore
4707
4708 @node Common Options
4709 @chapter Common Options
4710
4711 The following command-line options are supported by all of the
4712 programs described in this manual.
4713
4714 @c man begin OPTIONS
4715 @table @env
4716 @include at-file.texi
4717 @c man end
4718
4719 @item --help
4720 Display the command-line options supported by the program.
4721
4722 @item --version
4723 Display the version number of the program.
4724
4725 @c man begin OPTIONS
4726 @end table
4727 @c man end
4728
4729 @node Selecting the Target System
4730 @chapter Selecting the Target System
4731
4732 You can specify two aspects of the target system to the @sc{gnu}
4733 binary file utilities, each in several ways:
4734
4735 @itemize @bullet
4736 @item
4737 the target
4738
4739 @item
4740 the architecture
4741 @end itemize
4742
4743 In the following summaries, the lists of ways to specify values are in
4744 order of decreasing precedence. The ways listed first override those
4745 listed later.
4746
4747 The commands to list valid values only list the values for which the
4748 programs you are running were configured. If they were configured with
4749 @option{--enable-targets=all}, the commands list most of the available
4750 values, but a few are left out; not all targets can be configured in at
4751 once because some of them can only be configured @dfn{native} (on hosts
4752 with the same type as the target system).
4753
4754 @menu
4755 * Target Selection::
4756 * Architecture Selection::
4757 @end menu
4758
4759 @node Target Selection
4760 @section Target Selection
4761
4762 A @dfn{target} is an object file format. A given target may be
4763 supported for multiple architectures (@pxref{Architecture Selection}).
4764 A target selection may also have variations for different operating
4765 systems or architectures.
4766
4767 The command to list valid target values is @samp{objdump -i}
4768 (the first column of output contains the relevant information).
4769
4770 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4771 @samp{a.out-sunos-big}.
4772
4773 You can also specify a target using a configuration triplet. This is
4774 the same sort of name that is passed to @file{configure} to specify a
4775 target. When you use a configuration triplet as an argument, it must be
4776 fully canonicalized. You can see the canonical version of a triplet by
4777 running the shell script @file{config.sub} which is included with the
4778 sources.
4779
4780 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4781 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4782
4783 @subheading @command{objdump} Target
4784
4785 Ways to specify:
4786
4787 @enumerate
4788 @item
4789 command line option: @option{-b} or @option{--target}
4790
4791 @item
4792 environment variable @code{GNUTARGET}
4793
4794 @item
4795 deduced from the input file
4796 @end enumerate
4797
4798 @subheading @command{objcopy} and @command{strip} Input Target
4799
4800 Ways to specify:
4801
4802 @enumerate
4803 @item
4804 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4805
4806 @item
4807 environment variable @code{GNUTARGET}
4808
4809 @item
4810 deduced from the input file
4811 @end enumerate
4812
4813 @subheading @command{objcopy} and @command{strip} Output Target
4814
4815 Ways to specify:
4816
4817 @enumerate
4818 @item
4819 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4820
4821 @item
4822 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4823
4824 @item
4825 environment variable @code{GNUTARGET}
4826
4827 @item
4828 deduced from the input file
4829 @end enumerate
4830
4831 @subheading @command{nm}, @command{size}, and @command{strings} Target
4832
4833 Ways to specify:
4834
4835 @enumerate
4836 @item
4837 command line option: @option{--target}
4838
4839 @item
4840 environment variable @code{GNUTARGET}
4841
4842 @item
4843 deduced from the input file
4844 @end enumerate
4845
4846 @node Architecture Selection
4847 @section Architecture Selection
4848
4849 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4850 to run. Its name may contain a colon, separating the name of the
4851 processor family from the name of the particular @sc{cpu}.
4852
4853 The command to list valid architecture values is @samp{objdump -i} (the
4854 second column contains the relevant information).
4855
4856 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4857
4858 @subheading @command{objdump} Architecture
4859
4860 Ways to specify:
4861
4862 @enumerate
4863 @item
4864 command line option: @option{-m} or @option{--architecture}
4865
4866 @item
4867 deduced from the input file
4868 @end enumerate
4869
4870 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4871
4872 Ways to specify:
4873
4874 @enumerate
4875 @item
4876 deduced from the input file
4877 @end enumerate
4878
4879 @node Reporting Bugs
4880 @chapter Reporting Bugs
4881 @cindex bugs
4882 @cindex reporting bugs
4883
4884 Your bug reports play an essential role in making the binary utilities
4885 reliable.
4886
4887 Reporting a bug may help you by bringing a solution to your problem, or
4888 it may not. But in any case the principal function of a bug report is
4889 to help the entire community by making the next version of the binary
4890 utilities work better. Bug reports are your contribution to their
4891 maintenance.
4892
4893 In order for a bug report to serve its purpose, you must include the
4894 information that enables us to fix the bug.
4895
4896 @menu
4897 * Bug Criteria:: Have you found a bug?
4898 * Bug Reporting:: How to report bugs
4899 @end menu
4900
4901 @node Bug Criteria
4902 @section Have You Found a Bug?
4903 @cindex bug criteria
4904
4905 If you are not sure whether you have found a bug, here are some guidelines:
4906
4907 @itemize @bullet
4908 @cindex fatal signal
4909 @cindex crash
4910 @item
4911 If a binary utility gets a fatal signal, for any input whatever, that is
4912 a bug. Reliable utilities never crash.
4913
4914 @cindex error on valid input
4915 @item
4916 If a binary utility produces an error message for valid input, that is a
4917 bug.
4918
4919 @item
4920 If you are an experienced user of binary utilities, your suggestions for
4921 improvement are welcome in any case.
4922 @end itemize
4923
4924 @node Bug Reporting
4925 @section How to Report Bugs
4926 @cindex bug reports
4927 @cindex bugs, reporting
4928
4929 A number of companies and individuals offer support for @sc{gnu}
4930 products. If you obtained the binary utilities from a support
4931 organization, we recommend you contact that organization first.
4932
4933 You can find contact information for many support companies and
4934 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4935 distribution.
4936
4937 @ifset BUGURL
4938 In any event, we also recommend that you send bug reports for the binary
4939 utilities to @value{BUGURL}.
4940 @end ifset
4941
4942 The fundamental principle of reporting bugs usefully is this:
4943 @strong{report all the facts}. If you are not sure whether to state a
4944 fact or leave it out, state it!
4945
4946 Often people omit facts because they think they know what causes the
4947 problem and assume that some details do not matter. Thus, you might
4948 assume that the name of a file you use in an example does not matter.
4949 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4950 a stray memory reference which happens to fetch from the location where
4951 that pathname is stored in memory; perhaps, if the pathname were
4952 different, the contents of that location would fool the utility into
4953 doing the right thing despite the bug. Play it safe and give a
4954 specific, complete example. That is the easiest thing for you to do,
4955 and the most helpful.
4956
4957 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4958 it is new to us. Therefore, always write your bug reports on the assumption
4959 that the bug has not been reported previously.
4960
4961 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4962 bell?'' This cannot help us fix a bug, so it is basically useless. We
4963 respond by asking for enough details to enable us to investigate.
4964 You might as well expedite matters by sending them to begin with.
4965
4966 To enable us to fix the bug, you should include all these things:
4967
4968 @itemize @bullet
4969 @item
4970 The version of the utility. Each utility announces it if you start it
4971 with the @option{--version} argument.
4972
4973 Without this, we will not know whether there is any point in looking for
4974 the bug in the current version of the binary utilities.
4975
4976 @item
4977 Any patches you may have applied to the source, including any patches
4978 made to the @code{BFD} library.
4979
4980 @item
4981 The type of machine you are using, and the operating system name and
4982 version number.
4983
4984 @item
4985 What compiler (and its version) was used to compile the utilities---e.g.
4986 ``@code{gcc-2.7}''.
4987
4988 @item
4989 The command arguments you gave the utility to observe the bug. To
4990 guarantee you will not omit something important, list them all. A copy
4991 of the Makefile (or the output from make) is sufficient.
4992
4993 If we were to try to guess the arguments, we would probably guess wrong
4994 and then we might not encounter the bug.
4995
4996 @item
4997 A complete input file, or set of input files, that will reproduce the
4998 bug. If the utility is reading an object file or files, then it is
4999 generally most helpful to send the actual object files.
5000
5001 If the source files were produced exclusively using @sc{gnu} programs
5002 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5003 may be OK to send the source files rather than the object files. In
5004 this case, be sure to say exactly what version of @command{gcc}, or
5005 whatever, was used to produce the object files. Also say how
5006 @command{gcc}, or whatever, was configured.
5007
5008 @item
5009 A description of what behavior you observe that you believe is
5010 incorrect. For example, ``It gets a fatal signal.''
5011
5012 Of course, if the bug is that the utility gets a fatal signal, then we
5013 will certainly notice it. But if the bug is incorrect output, we might
5014 not notice unless it is glaringly wrong. You might as well not give us
5015 a chance to make a mistake.
5016
5017 Even if the problem you experience is a fatal signal, you should still
5018 say so explicitly. Suppose something strange is going on, such as your
5019 copy of the utility is out of sync, or you have encountered a bug in
5020 the C library on your system. (This has happened!) Your copy might
5021 crash and ours would not. If you told us to expect a crash, then when
5022 ours fails to crash, we would know that the bug was not happening for
5023 us. If you had not told us to expect a crash, then we would not be able
5024 to draw any conclusion from our observations.
5025
5026 @item
5027 If you wish to suggest changes to the source, send us context diffs, as
5028 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5029 option. Always send diffs from the old file to the new file. If you
5030 wish to discuss something in the @command{ld} source, refer to it by
5031 context, not by line number.
5032
5033 The line numbers in our development sources will not match those in your
5034 sources. Your line numbers would convey no useful information to us.
5035 @end itemize
5036
5037 Here are some things that are not necessary:
5038
5039 @itemize @bullet
5040 @item
5041 A description of the envelope of the bug.
5042
5043 Often people who encounter a bug spend a lot of time investigating
5044 which changes to the input file will make the bug go away and which
5045 changes will not affect it.
5046
5047 This is often time consuming and not very useful, because the way we
5048 will find the bug is by running a single example under the debugger
5049 with breakpoints, not by pure deduction from a series of examples.
5050 We recommend that you save your time for something else.
5051
5052 Of course, if you can find a simpler example to report @emph{instead}
5053 of the original one, that is a convenience for us. Errors in the
5054 output will be easier to spot, running under the debugger will take
5055 less time, and so on.
5056
5057 However, simplification is not vital; if you do not want to do this,
5058 report the bug anyway and send us the entire test case you used.
5059
5060 @item
5061 A patch for the bug.
5062
5063 A patch for the bug does help us if it is a good one. But do not omit
5064 the necessary information, such as the test case, on the assumption that
5065 a patch is all we need. We might see problems with your patch and decide
5066 to fix the problem another way, or we might not understand it at all.
5067
5068 Sometimes with programs as complicated as the binary utilities it is
5069 very hard to construct an example that will make the program follow a
5070 certain path through the code. If you do not send us the example, we
5071 will not be able to construct one, so we will not be able to verify that
5072 the bug is fixed.
5073
5074 And if we cannot understand what bug you are trying to fix, or why your
5075 patch should be an improvement, we will not install it. A test case will
5076 help us to understand.
5077
5078 @item
5079 A guess about what the bug is or what it depends on.
5080
5081 Such guesses are usually wrong. Even we cannot guess right about such
5082 things without first using the debugger to find the facts.
5083 @end itemize
5084
5085 @node GNU Free Documentation License
5086 @appendix GNU Free Documentation License
5087
5088 @include fdl.texi
5089
5090 @node Binutils Index
5091 @unnumbered Binutils Index
5092
5093 @printindex cp
5094
5095 @bye
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