Remove sentance in binutils documentation saying that thin archives cannot contain...
[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{--help}] [@option{--version}] @var{file}@dots{}
2794 @c man end
2795 @end smallexample
2796
2797 @c man begin DESCRIPTION strings
2798
2799 For each @var{file} given, @sc{gnu} @command{strings} prints the
2800 printable character sequences that are at least 4 characters long (or
2801 the number given with the options below) and are followed by an
2802 unprintable character.
2803
2804 Depending upon how the strings program was configured it will default
2805 to either displaying all the printable sequences that it can find in
2806 each file, or only those sequences that are in loadable, initialized
2807 data sections. If the file type in unrecognizable, or if strings is
2808 reading from stdin then it will always display all of the printable
2809 sequences that it can find.
2810
2811 For backwards compatibility any file that occurs after a command line
2812 option of just @option{-} will also be scanned in full, regardless of
2813 the presence of any @option{-d} option.
2814
2815 @command{strings} is mainly useful for determining the contents of
2816 non-text files.
2817
2818 @c man end
2819
2820 @c man begin OPTIONS strings
2821
2822 @table @env
2823 @item -a
2824 @itemx --all
2825 @itemx -
2826 Scan the whole file, regardless of what sections it contains or
2827 whether those sections are loaded or initialized. Normally this is
2828 the default behaviour, but strings can be configured so that the
2829 @option{-d} is the default instead.
2830
2831 The @option{-} option is position dependent and forces strings to
2832 perform full scans of any file that is mentioned after the @option{-}
2833 on the command line, even if the @option{-d} option has been
2834 specified.
2835
2836 @item -d
2837 @itemx --data
2838 Only print strings from initialized, loaded data sections in the
2839 file. This may reduce the amount of garbage in the output, but it
2840 also exposes the strings program to any security flaws that may be
2841 present in the BFD library used to scan and load sections. Strings
2842 can be configured so that this option is the default behaviour. In
2843 such cases the @option{-a} option can be used to avoid using the BFD
2844 library and instead just print all of the strings found in the file.
2845
2846 @item -f
2847 @itemx --print-file-name
2848 Print the name of the file before each string.
2849
2850 @item --help
2851 Print a summary of the program usage on the standard output and exit.
2852
2853 @item -@var{min-len}
2854 @itemx -n @var{min-len}
2855 @itemx --bytes=@var{min-len}
2856 Print sequences of characters that are at least @var{min-len} characters
2857 long, instead of the default 4.
2858
2859 @item -o
2860 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2861 act like @samp{-t d} instead. Since we can not be compatible with both
2862 ways, we simply chose one.
2863
2864 @item -t @var{radix}
2865 @itemx --radix=@var{radix}
2866 Print the offset within the file before each string. The single
2867 character argument specifies the radix of the offset---@samp{o} for
2868 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2869
2870 @item -e @var{encoding}
2871 @itemx --encoding=@var{encoding}
2872 Select the character encoding of the strings that are to be found.
2873 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2874 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2875 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2876 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2877 littleendian. Useful for finding wide character strings. (@samp{l}
2878 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
2879
2880 @item -T @var{bfdname}
2881 @itemx --target=@var{bfdname}
2882 @cindex object code format
2883 Specify an object code format other than your system's default format.
2884 @xref{Target Selection}, for more information.
2885
2886 @item -v
2887 @itemx -V
2888 @itemx --version
2889 Print the program version number on the standard output and exit.
2890
2891 @item -w
2892 @itemx --include-all-whitespace
2893 By default tab and space characters are included in the strings that
2894 are displayed, but other whitespace characters, such a newlines and
2895 carriage returns, are not. The @option{-w} option changes this so
2896 that all whitespace characters are considered to be part of a string.
2897 @end table
2898
2899 @c man end
2900
2901 @ignore
2902 @c man begin SEEALSO strings
2903 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2904 and the Info entries for @file{binutils}.
2905 @c man end
2906 @end ignore
2907
2908 @node strip
2909 @chapter strip
2910
2911 @kindex strip
2912 @cindex removing symbols
2913 @cindex discarding symbols
2914 @cindex symbols, discarding
2915
2916 @c man title strip Discard symbols from object files.
2917
2918 @smallexample
2919 @c man begin SYNOPSIS strip
2920 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2921 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2922 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2923 [@option{-s}|@option{--strip-all}]
2924 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2925 [@option{--strip-dwo}]
2926 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2927 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2928 [@option{-w}|@option{--wildcard}]
2929 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2930 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2931 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2932 [@option{-D}|@option{--enable-deterministic-archives}]
2933 [@option{-U}|@option{--disable-deterministic-archives}]
2934 [@option{--keep-file-symbols}]
2935 [@option{--only-keep-debug}]
2936 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2937 [@option{--help}] [@option{--info}]
2938 @var{objfile}@dots{}
2939 @c man end
2940 @end smallexample
2941
2942 @c man begin DESCRIPTION strip
2943
2944 @sc{gnu} @command{strip} discards all symbols from object files
2945 @var{objfile}. The list of object files may include archives.
2946 At least one object file must be given.
2947
2948 @command{strip} modifies the files named in its argument,
2949 rather than writing modified copies under different names.
2950
2951 @c man end
2952
2953 @c man begin OPTIONS strip
2954
2955 @table @env
2956 @item -F @var{bfdname}
2957 @itemx --target=@var{bfdname}
2958 Treat the original @var{objfile} as a file with the object
2959 code format @var{bfdname}, and rewrite it in the same format.
2960 @xref{Target Selection}, for more information.
2961
2962 @item --help
2963 Show a summary of the options to @command{strip} and exit.
2964
2965 @item --info
2966 Display a list showing all architectures and object formats available.
2967
2968 @item -I @var{bfdname}
2969 @itemx --input-target=@var{bfdname}
2970 Treat the original @var{objfile} as a file with the object
2971 code format @var{bfdname}.
2972 @xref{Target Selection}, for more information.
2973
2974 @item -O @var{bfdname}
2975 @itemx --output-target=@var{bfdname}
2976 Replace @var{objfile} with a file in the output format @var{bfdname}.
2977 @xref{Target Selection}, for more information.
2978
2979 @item -R @var{sectionname}
2980 @itemx --remove-section=@var{sectionname}
2981 Remove any section named @var{sectionname} from the output file, in
2982 addition to whatever sections would otherwise be removed. This
2983 option may be given more than once. Note that using this option
2984 inappropriately may make the output file unusable. The wildcard
2985 character @samp{*} may be given at the end of @var{sectionname}. If
2986 so, then any section starting with @var{sectionname} will be removed.
2987
2988 @item -s
2989 @itemx --strip-all
2990 Remove all symbols.
2991
2992 @item -g
2993 @itemx -S
2994 @itemx -d
2995 @itemx --strip-debug
2996 Remove debugging symbols only.
2997
2998 @item --strip-dwo
2999 Remove the contents of all DWARF .dwo sections, leaving the
3000 remaining debugging sections and all symbols intact.
3001 See the description of this option in the @command{objcopy} section
3002 for more information.
3003
3004 @item --strip-unneeded
3005 Remove all symbols that are not needed for relocation processing.
3006
3007 @item -K @var{symbolname}
3008 @itemx --keep-symbol=@var{symbolname}
3009 When stripping symbols, keep symbol @var{symbolname} even if it would
3010 normally be stripped. This option may be given more than once.
3011
3012 @item -N @var{symbolname}
3013 @itemx --strip-symbol=@var{symbolname}
3014 Remove symbol @var{symbolname} from the source file. This option may be
3015 given more than once, and may be combined with strip options other than
3016 @option{-K}.
3017
3018 @item -o @var{file}
3019 Put the stripped output in @var{file}, rather than replacing the
3020 existing file. When this argument is used, only one @var{objfile}
3021 argument may be specified.
3022
3023 @item -p
3024 @itemx --preserve-dates
3025 Preserve the access and modification dates of the file.
3026
3027 @item -D
3028 @itemx --enable-deterministic-archives
3029 @cindex deterministic archives
3030 @kindex --enable-deterministic-archives
3031 Operate in @emph{deterministic} mode. When copying archive members
3032 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3033 and use consistent file modes for all files.
3034
3035 If @file{binutils} was configured with
3036 @option{--enable-deterministic-archives}, then this mode is on by default.
3037 It can be disabled with the @samp{-U} option, below.
3038
3039 @item -U
3040 @itemx --disable-deterministic-archives
3041 @cindex deterministic archives
3042 @kindex --enable-deterministic-archives
3043 Do @emph{not} operate in @emph{deterministic} mode. This is the
3044 inverse of the @option{-D} option, above: when copying archive members
3045 and writing the archive index, use their actual UID, GID, timestamp,
3046 and file mode values.
3047
3048 This is the default unless @file{binutils} was configured with
3049 @option{--enable-deterministic-archives}.
3050
3051 @item -w
3052 @itemx --wildcard
3053 Permit regular expressions in @var{symbolname}s used in other command
3054 line options. The question mark (?), asterisk (*), backslash (\) and
3055 square brackets ([]) operators can be used anywhere in the symbol
3056 name. If the first character of the symbol name is the exclamation
3057 point (!) then the sense of the switch is reversed for that symbol.
3058 For example:
3059
3060 @smallexample
3061 -w -K !foo -K fo*
3062 @end smallexample
3063
3064 would cause strip to only keep symbols that start with the letters
3065 ``fo'', but to discard the symbol ``foo''.
3066
3067 @item -x
3068 @itemx --discard-all
3069 Remove non-global symbols.
3070
3071 @item -X
3072 @itemx --discard-locals
3073 Remove compiler-generated local symbols.
3074 (These usually start with @samp{L} or @samp{.}.)
3075
3076 @item --keep-file-symbols
3077 When stripping a file, perhaps with @option{--strip-debug} or
3078 @option{--strip-unneeded}, retain any symbols specifying source file names,
3079 which would otherwise get stripped.
3080
3081 @item --only-keep-debug
3082 Strip a file, emptying the contents of any sections that would not be
3083 stripped by @option{--strip-debug} and leaving the debugging sections
3084 intact. In ELF files, this preserves all the note sections in the
3085 output as well.
3086
3087 Note - the section headers of the stripped sections are preserved,
3088 including their sizes, but the contents of the section are discarded.
3089 The section headers are preserved so that other tools can match up the
3090 debuginfo file with the real executable, even if that executable has
3091 been relocated to a different address space.
3092
3093 The intention is that this option will be used in conjunction with
3094 @option{--add-gnu-debuglink} to create a two part executable. One a
3095 stripped binary which will occupy less space in RAM and in a
3096 distribution and the second a debugging information file which is only
3097 needed if debugging abilities are required. The suggested procedure
3098 to create these files is as follows:
3099
3100 @enumerate
3101 @item Link the executable as normal. Assuming that is is called
3102 @code{foo} then...
3103 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3104 create a file containing the debugging info.
3105 @item Run @code{objcopy --strip-debug foo} to create a
3106 stripped executable.
3107 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3108 to add a link to the debugging info into the stripped executable.
3109 @end enumerate
3110
3111 Note---the choice of @code{.dbg} as an extension for the debug info
3112 file is arbitrary. Also the @code{--only-keep-debug} step is
3113 optional. You could instead do this:
3114
3115 @enumerate
3116 @item Link the executable as normal.
3117 @item Copy @code{foo} to @code{foo.full}
3118 @item Run @code{strip --strip-debug foo}
3119 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3120 @end enumerate
3121
3122 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3123 full executable. It does not have to be a file created by the
3124 @option{--only-keep-debug} switch.
3125
3126 Note---this switch is only intended for use on fully linked files. It
3127 does not make sense to use it on object files where the debugging
3128 information may be incomplete. Besides the gnu_debuglink feature
3129 currently only supports the presence of one filename containing
3130 debugging information, not multiple filenames on a one-per-object-file
3131 basis.
3132
3133 @item -V
3134 @itemx --version
3135 Show the version number for @command{strip}.
3136
3137 @item -v
3138 @itemx --verbose
3139 Verbose output: list all object files modified. In the case of
3140 archives, @samp{strip -v} lists all members of the archive.
3141 @end table
3142
3143 @c man end
3144
3145 @ignore
3146 @c man begin SEEALSO strip
3147 the Info entries for @file{binutils}.
3148 @c man end
3149 @end ignore
3150
3151 @node c++filt, addr2line, strip, Top
3152 @chapter c++filt
3153
3154 @kindex c++filt
3155 @cindex demangling C++ symbols
3156
3157 @c man title cxxfilt Demangle C++ and Java symbols.
3158
3159 @smallexample
3160 @c man begin SYNOPSIS cxxfilt
3161 c++filt [@option{-_}|@option{--strip-underscore}]
3162 [@option{-n}|@option{--no-strip-underscore}]
3163 [@option{-p}|@option{--no-params}]
3164 [@option{-t}|@option{--types}]
3165 [@option{-i}|@option{--no-verbose}]
3166 [@option{-s} @var{format}|@option{--format=}@var{format}]
3167 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3168 @c man end
3169 @end smallexample
3170
3171 @c man begin DESCRIPTION cxxfilt
3172
3173 @kindex cxxfilt
3174 The C++ and Java languages provide function overloading, which means
3175 that you can write many functions with the same name, providing that
3176 each function takes parameters of different types. In order to be
3177 able to distinguish these similarly named functions C++ and Java
3178 encode them into a low-level assembler name which uniquely identifies
3179 each different version. This process is known as @dfn{mangling}. The
3180 @command{c++filt}
3181 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3182 MS-DOS this program is named @command{CXXFILT}.}
3183 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3184 names into user-level names so that they can be read.
3185
3186 Every alphanumeric word (consisting of letters, digits, underscores,
3187 dollars, or periods) seen in the input is a potential mangled name.
3188 If the name decodes into a C++ name, the C++ name replaces the
3189 low-level name in the output, otherwise the original word is output.
3190 In this way you can pass an entire assembler source file, containing
3191 mangled names, through @command{c++filt} and see the same source file
3192 containing demangled names.
3193
3194 You can also use @command{c++filt} to decipher individual symbols by
3195 passing them on the command line:
3196
3197 @example
3198 c++filt @var{symbol}
3199 @end example
3200
3201 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3202 names from the standard input instead. All the results are printed on
3203 the standard output. The difference between reading names from the
3204 command line versus reading names from the standard input is that
3205 command line arguments are expected to be just mangled names and no
3206 checking is performed to separate them from surrounding text. Thus
3207 for example:
3208
3209 @smallexample
3210 c++filt -n _Z1fv
3211 @end smallexample
3212
3213 will work and demangle the name to ``f()'' whereas:
3214
3215 @smallexample
3216 c++filt -n _Z1fv,
3217 @end smallexample
3218
3219 will not work. (Note the extra comma at the end of the mangled
3220 name which makes it invalid). This command however will work:
3221
3222 @smallexample
3223 echo _Z1fv, | c++filt -n
3224 @end smallexample
3225
3226 and will display ``f(),'', i.e., the demangled name followed by a
3227 trailing comma. This behaviour is because when the names are read
3228 from the standard input it is expected that they might be part of an
3229 assembler source file where there might be extra, extraneous
3230 characters trailing after a mangled name. For example:
3231
3232 @smallexample
3233 .type _Z1fv, @@function
3234 @end smallexample
3235
3236 @c man end
3237
3238 @c man begin OPTIONS cxxfilt
3239
3240 @table @env
3241 @item -_
3242 @itemx --strip-underscore
3243 On some systems, both the C and C++ compilers put an underscore in front
3244 of every name. For example, the C name @code{foo} gets the low-level
3245 name @code{_foo}. This option removes the initial underscore. Whether
3246 @command{c++filt} removes the underscore by default is target dependent.
3247
3248 @item -n
3249 @itemx --no-strip-underscore
3250 Do not remove the initial underscore.
3251
3252 @item -p
3253 @itemx --no-params
3254 When demangling the name of a function, do not display the types of
3255 the function's parameters.
3256
3257 @item -t
3258 @itemx --types
3259 Attempt to demangle types as well as function names. This is disabled
3260 by default since mangled types are normally only used internally in
3261 the compiler, and they can be confused with non-mangled names. For example,
3262 a function called ``a'' treated as a mangled type name would be
3263 demangled to ``signed char''.
3264
3265 @item -i
3266 @itemx --no-verbose
3267 Do not include implementation details (if any) in the demangled
3268 output.
3269
3270 @item -s @var{format}
3271 @itemx --format=@var{format}
3272 @command{c++filt} can decode various methods of mangling, used by
3273 different compilers. The argument to this option selects which
3274 method it uses:
3275
3276 @table @code
3277 @item auto
3278 Automatic selection based on executable (the default method)
3279 @item gnu
3280 the one used by the @sc{gnu} C++ compiler (g++)
3281 @item lucid
3282 the one used by the Lucid compiler (lcc)
3283 @item arm
3284 the one specified by the C++ Annotated Reference Manual
3285 @item hp
3286 the one used by the HP compiler (aCC)
3287 @item edg
3288 the one used by the EDG compiler
3289 @item gnu-v3
3290 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3291 @item java
3292 the one used by the @sc{gnu} Java compiler (gcj)
3293 @item gnat
3294 the one used by the @sc{gnu} Ada compiler (GNAT).
3295 @end table
3296
3297 @item --help
3298 Print a summary of the options to @command{c++filt} and exit.
3299
3300 @item --version
3301 Print the version number of @command{c++filt} and exit.
3302 @end table
3303
3304 @c man end
3305
3306 @ignore
3307 @c man begin SEEALSO cxxfilt
3308 the Info entries for @file{binutils}.
3309 @c man end
3310 @end ignore
3311
3312 @quotation
3313 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3314 user interface are subject to change in future releases. In particular,
3315 a command-line option may be required in the future to decode a name
3316 passed as an argument on the command line; in other words,
3317
3318 @example
3319 c++filt @var{symbol}
3320 @end example
3321
3322 @noindent
3323 may in a future release become
3324
3325 @example
3326 c++filt @var{option} @var{symbol}
3327 @end example
3328 @end quotation
3329
3330 @node addr2line
3331 @chapter addr2line
3332
3333 @kindex addr2line
3334 @cindex address to file name and line number
3335
3336 @c man title addr2line convert addresses into file names and line numbers.
3337
3338 @smallexample
3339 @c man begin SYNOPSIS addr2line
3340 addr2line [@option{-a}|@option{--addresses}]
3341 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3342 [@option{-C}|@option{--demangle}[=@var{style}]]
3343 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3344 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3345 [@option{-i}|@option{--inlines}]
3346 [@option{-p}|@option{--pretty-print}]
3347 [@option{-j}|@option{--section=}@var{name}]
3348 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3349 [addr addr @dots{}]
3350 @c man end
3351 @end smallexample
3352
3353 @c man begin DESCRIPTION addr2line
3354
3355 @command{addr2line} translates addresses into file names and line numbers.
3356 Given an address in an executable or an offset in a section of a relocatable
3357 object, it uses the debugging information to figure out which file name and
3358 line number are associated with it.
3359
3360 The executable or relocatable object to use is specified with the @option{-e}
3361 option. The default is the file @file{a.out}. The section in the relocatable
3362 object to use is specified with the @option{-j} option.
3363
3364 @command{addr2line} has two modes of operation.
3365
3366 In the first, hexadecimal addresses are specified on the command line,
3367 and @command{addr2line} displays the file name and line number for each
3368 address.
3369
3370 In the second, @command{addr2line} reads hexadecimal addresses from
3371 standard input, and prints the file name and line number for each
3372 address on standard output. In this mode, @command{addr2line} may be used
3373 in a pipe to convert dynamically chosen addresses.
3374
3375 The format of the output is @samp{FILENAME:LINENO}. By default
3376 each input address generates one line of output.
3377
3378 Two options can generate additional lines before each
3379 @samp{FILENAME:LINENO} line (in that order).
3380
3381 If the @option{-a} option is used then a line with the input address
3382 is displayed.
3383
3384 If the @option{-f} option is used, then a line with the
3385 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3386 containing the address.
3387
3388 One option can generate additional lines after the
3389 @samp{FILENAME:LINENO} line.
3390
3391 If the @option{-i} option is used and the code at the given address is
3392 present there because of inlining by the compiler then additional
3393 lines are displayed afterwards. One or two extra lines (if the
3394 @option{-f} option is used) are displayed for each inlined function.
3395
3396 Alternatively if the @option{-p} option is used then each input
3397 address generates a single, long, output line containing the address,
3398 the function name, the file name and the line number. If the
3399 @option{-i} option has also been used then any inlined functions will
3400 be displayed in the same manner, but on separate lines, and prefixed
3401 by the text @samp{(inlined by)}.
3402
3403 If the file name or function name can not be determined,
3404 @command{addr2line} will print two question marks in their place. If the
3405 line number can not be determined, @command{addr2line} will print 0.
3406
3407 @c man end
3408
3409 @c man begin OPTIONS addr2line
3410
3411 The long and short forms of options, shown here as alternatives, are
3412 equivalent.
3413
3414 @table @env
3415 @item -a
3416 @itemx --addresses
3417 Display the address before the function name, file and line number
3418 information. The address is printed with a @samp{0x} prefix to easily
3419 identify it.
3420
3421 @item -b @var{bfdname}
3422 @itemx --target=@var{bfdname}
3423 @cindex object code format
3424 Specify that the object-code format for the object files is
3425 @var{bfdname}.
3426
3427 @item -C
3428 @itemx --demangle[=@var{style}]
3429 @cindex demangling in objdump
3430 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3431 Besides removing any initial underscore prepended by the system, this
3432 makes C++ function names readable. Different compilers have different
3433 mangling styles. The optional demangling style argument can be used to
3434 choose an appropriate demangling style for your compiler. @xref{c++filt},
3435 for more information on demangling.
3436
3437 @item -e @var{filename}
3438 @itemx --exe=@var{filename}
3439 Specify the name of the executable for which addresses should be
3440 translated. The default file is @file{a.out}.
3441
3442 @item -f
3443 @itemx --functions
3444 Display function names as well as file and line number information.
3445
3446 @item -s
3447 @itemx --basenames
3448 Display only the base of each file name.
3449
3450 @item -i
3451 @itemx --inlines
3452 If the address belongs to a function that was inlined, the source
3453 information for all enclosing scopes back to the first non-inlined
3454 function will also be printed. For example, if @code{main} inlines
3455 @code{callee1} which inlines @code{callee2}, and address is from
3456 @code{callee2}, the source information for @code{callee1} and @code{main}
3457 will also be printed.
3458
3459 @item -j
3460 @itemx --section
3461 Read offsets relative to the specified section instead of absolute addresses.
3462
3463 @item -p
3464 @itemx --pretty-print
3465 Make the output more human friendly: each location are printed on one line.
3466 If option @option{-i} is specified, lines for all enclosing scopes are
3467 prefixed with @samp{(inlined by)}.
3468 @end table
3469
3470 @c man end
3471
3472 @ignore
3473 @c man begin SEEALSO addr2line
3474 Info entries for @file{binutils}.
3475 @c man end
3476 @end ignore
3477
3478 @node nlmconv
3479 @chapter nlmconv
3480
3481 @command{nlmconv} converts a relocatable object file into a NetWare
3482 Loadable Module.
3483
3484 @ignore
3485 @command{nlmconv} currently works with @samp{i386} object
3486 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3487 object files in @sc{elf}, or @code{a.out} format@footnote{
3488 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3489 format in the Binary File Descriptor library. It has only been tested
3490 with the above formats.}.
3491 @end ignore
3492
3493 @quotation
3494 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3495 utilities, since it is only useful for NLM targets.
3496 @end quotation
3497
3498 @c man title nlmconv converts object code into an NLM.
3499
3500 @smallexample
3501 @c man begin SYNOPSIS nlmconv
3502 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3503 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3504 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3505 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3506 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3507 @var{infile} @var{outfile}
3508 @c man end
3509 @end smallexample
3510
3511 @c man begin DESCRIPTION nlmconv
3512
3513 @command{nlmconv} converts the relocatable @samp{i386} object file
3514 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3515 reading @var{headerfile} for NLM header information. For instructions
3516 on writing the NLM command file language used in header files, see the
3517 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3518 Development and Tools Overview}, which is part of the NLM Software
3519 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3520 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3521 @var{infile};
3522 @ifclear man
3523 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3524 @end ifclear
3525
3526 @command{nlmconv} can perform a link step. In other words, you can list
3527 more than one object file for input if you list them in the definitions
3528 file (rather than simply specifying one input file on the command line).
3529 In this case, @command{nlmconv} calls the linker for you.
3530
3531 @c man end
3532
3533 @c man begin OPTIONS nlmconv
3534
3535 @table @env
3536 @item -I @var{bfdname}
3537 @itemx --input-target=@var{bfdname}
3538 Object format of the input file. @command{nlmconv} can usually determine
3539 the format of a given file (so no default is necessary).
3540 @xref{Target Selection}, for more information.
3541
3542 @item -O @var{bfdname}
3543 @itemx --output-target=@var{bfdname}
3544 Object format of the output file. @command{nlmconv} infers the output
3545 format based on the input format, e.g. for a @samp{i386} input file the
3546 output format is @samp{nlm32-i386}.
3547 @xref{Target Selection}, for more information.
3548
3549 @item -T @var{headerfile}
3550 @itemx --header-file=@var{headerfile}
3551 Reads @var{headerfile} for NLM header information. For instructions on
3552 writing the NLM command file language used in header files, see@ see the
3553 @samp{linkers} section, of the @cite{NLM Development and Tools
3554 Overview}, which is part of the NLM Software Developer's Kit, available
3555 from Novell, Inc.
3556
3557 @item -d
3558 @itemx --debug
3559 Displays (on standard error) the linker command line used by @command{nlmconv}.
3560
3561 @item -l @var{linker}
3562 @itemx --linker=@var{linker}
3563 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3564 relative pathname.
3565
3566 @item -h
3567 @itemx --help
3568 Prints a usage summary.
3569
3570 @item -V
3571 @itemx --version
3572 Prints the version number for @command{nlmconv}.
3573 @end table
3574
3575 @c man end
3576
3577 @ignore
3578 @c man begin SEEALSO nlmconv
3579 the Info entries for @file{binutils}.
3580 @c man end
3581 @end ignore
3582
3583 @node windmc
3584 @chapter windmc
3585
3586 @command{windmc} may be used to generator Windows message resources.
3587
3588 @quotation
3589 @emph{Warning:} @command{windmc} is not always built as part of the binary
3590 utilities, since it is only useful for Windows targets.
3591 @end quotation
3592
3593 @c man title windmc generates Windows message resources.
3594
3595 @smallexample
3596 @c man begin SYNOPSIS windmc
3597 windmc [options] input-file
3598 @c man end
3599 @end smallexample
3600
3601 @c man begin DESCRIPTION windmc
3602
3603 @command{windmc} reads message definitions from an input file (.mc) and
3604 translate them into a set of output files. The output files may be of
3605 four kinds:
3606
3607 @table @code
3608 @item h
3609 A C header file containing the message definitions.
3610
3611 @item rc
3612 A resource file compilable by the @command{windres} tool.
3613
3614 @item bin
3615 One or more binary files containing the resource data for a specific
3616 message language.
3617
3618 @item dbg
3619 A C include file that maps message id's to their symbolic name.
3620 @end table
3621
3622 The exact description of these different formats is available in
3623 documentation from Microsoft.
3624
3625 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3626 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3627 Windows Message Compiler.
3628
3629 @c man end
3630
3631 @c man begin OPTIONS windmc
3632
3633 @table @env
3634 @item -a
3635 @itemx --ascii_in
3636 Specifies that the input file specified is ASCII. This is the default
3637 behaviour.
3638
3639 @item -A
3640 @itemx --ascii_out
3641 Specifies that messages in the output @code{bin} files should be in ASCII
3642 format.
3643
3644 @item -b
3645 @itemx --binprefix
3646 Specifies that @code{bin} filenames should have to be prefixed by the
3647 basename of the source file.
3648
3649 @item -c
3650 @itemx --customflag
3651 Sets the customer bit in all message id's.
3652
3653 @item -C @var{codepage}
3654 @itemx --codepage_in @var{codepage}
3655 Sets the default codepage to be used to convert input file to UTF16. The
3656 default is ocdepage 1252.
3657
3658 @item -d
3659 @itemx --decimal_values
3660 Outputs the constants in the header file in decimal. Default is using
3661 hexadecimal output.
3662
3663 @item -e @var{ext}
3664 @itemx --extension @var{ext}
3665 The extension for the header file. The default is .h extension.
3666
3667 @item -F @var{target}
3668 @itemx --target @var{target}
3669 Specify the BFD format to use for a bin file as output. This
3670 is a BFD target name; you can use the @option{--help} option to see a list
3671 of supported targets. Normally @command{windmc} will use the default
3672 format, which is the first one listed by the @option{--help} option.
3673 @ifclear man
3674 @ref{Target Selection}.
3675 @end ifclear
3676
3677 @item -h @var{path}
3678 @itemx --headerdir @var{path}
3679 The target directory of the generated header file. The default is the
3680 current directory.
3681
3682 @item -H
3683 @itemx --help
3684 Displays a list of command line options and then exits.
3685
3686 @item -m @var{characters}
3687 @itemx --maxlength @var{characters}
3688 Instructs @command{windmc} to generate a warning if the length
3689 of any message exceeds the number specified.
3690
3691 @item -n
3692 @itemx --nullterminate
3693 Terminate message text in @code{bin} files by zero. By default they are
3694 terminated by CR/LF.
3695
3696 @item -o
3697 @itemx --hresult_use
3698 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3699 file, using HRESULT definitions. Status codes are used if the flag is not
3700 specified.
3701
3702 @item -O @var{codepage}
3703 @itemx --codepage_out @var{codepage}
3704 Sets the default codepage to be used to output text files. The default
3705 is ocdepage 1252.
3706
3707 @item -r @var{path}
3708 @itemx --rcdir @var{path}
3709 The target directory for the generated @code{rc} script and the generated
3710 @code{bin} files that the resource compiler script includes. The default
3711 is the current directory.
3712
3713 @item -u
3714 @itemx --unicode_in
3715 Specifies that the input file is UTF16.
3716
3717 @item -U
3718 @itemx --unicode_out
3719 Specifies that messages in the output @code{bin} file should be in UTF16
3720 format. This is the default behaviour.
3721
3722 @item -v
3723 @item --verbose
3724 Enable verbose mode.
3725
3726 @item -V
3727 @item --version
3728 Prints the version number for @command{windmc}.
3729
3730 @item -x @var{path}
3731 @itemx --xdgb @var{path}
3732 The path of the @code{dbg} C include file that maps message id's to the
3733 symbolic name. No such file is generated without specifying the switch.
3734 @end table
3735
3736 @c man end
3737
3738 @ignore
3739 @c man begin SEEALSO windmc
3740 the Info entries for @file{binutils}.
3741 @c man end
3742 @end ignore
3743
3744 @node windres
3745 @chapter windres
3746
3747 @command{windres} may be used to manipulate Windows resources.
3748
3749 @quotation
3750 @emph{Warning:} @command{windres} is not always built as part of the binary
3751 utilities, since it is only useful for Windows targets.
3752 @end quotation
3753
3754 @c man title windres manipulate Windows resources.
3755
3756 @smallexample
3757 @c man begin SYNOPSIS windres
3758 windres [options] [input-file] [output-file]
3759 @c man end
3760 @end smallexample
3761
3762 @c man begin DESCRIPTION windres
3763
3764 @command{windres} reads resources from an input file and copies them into
3765 an output file. Either file may be in one of three formats:
3766
3767 @table @code
3768 @item rc
3769 A text format read by the Resource Compiler.
3770
3771 @item res
3772 A binary format generated by the Resource Compiler.
3773
3774 @item coff
3775 A COFF object or executable.
3776 @end table
3777
3778 The exact description of these different formats is available in
3779 documentation from Microsoft.
3780
3781 When @command{windres} converts from the @code{rc} format to the @code{res}
3782 format, it is acting like the Windows Resource Compiler. When
3783 @command{windres} converts from the @code{res} format to the @code{coff}
3784 format, it is acting like the Windows @code{CVTRES} program.
3785
3786 When @command{windres} generates an @code{rc} file, the output is similar
3787 but not identical to the format expected for the input. When an input
3788 @code{rc} file refers to an external filename, an output @code{rc} file
3789 will instead include the file contents.
3790
3791 If the input or output format is not specified, @command{windres} will
3792 guess based on the file name, or, for the input file, the file contents.
3793 A file with an extension of @file{.rc} will be treated as an @code{rc}
3794 file, a file with an extension of @file{.res} will be treated as a
3795 @code{res} file, and a file with an extension of @file{.o} or
3796 @file{.exe} will be treated as a @code{coff} file.
3797
3798 If no output file is specified, @command{windres} will print the resources
3799 in @code{rc} format to standard output.
3800
3801 The normal use is for you to write an @code{rc} file, use @command{windres}
3802 to convert it to a COFF object file, and then link the COFF file into
3803 your application. This will make the resources described in the
3804 @code{rc} file available to Windows.
3805
3806 @c man end
3807
3808 @c man begin OPTIONS windres
3809
3810 @table @env
3811 @item -i @var{filename}
3812 @itemx --input @var{filename}
3813 The name of the input file. If this option is not used, then
3814 @command{windres} will use the first non-option argument as the input file
3815 name. If there are no non-option arguments, then @command{windres} will
3816 read from standard input. @command{windres} can not read a COFF file from
3817 standard input.
3818
3819 @item -o @var{filename}
3820 @itemx --output @var{filename}
3821 The name of the output file. If this option is not used, then
3822 @command{windres} will use the first non-option argument, after any used
3823 for the input file name, as the output file name. If there is no
3824 non-option argument, then @command{windres} will write to standard output.
3825 @command{windres} can not write a COFF file to standard output. Note,
3826 for compatibility with @command{rc} the option @option{-fo} is also
3827 accepted, but its use is not recommended.
3828
3829 @item -J @var{format}
3830 @itemx --input-format @var{format}
3831 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3832 @samp{coff}. If no input format is specified, @command{windres} will
3833 guess, as described above.
3834
3835 @item -O @var{format}
3836 @itemx --output-format @var{format}
3837 The output format to generate. @var{format} may be @samp{res},
3838 @samp{rc}, or @samp{coff}. If no output format is specified,
3839 @command{windres} will guess, as described above.
3840
3841 @item -F @var{target}
3842 @itemx --target @var{target}
3843 Specify the BFD format to use for a COFF file as input or output. This
3844 is a BFD target name; you can use the @option{--help} option to see a list
3845 of supported targets. Normally @command{windres} will use the default
3846 format, which is the first one listed by the @option{--help} option.
3847 @ifclear man
3848 @ref{Target Selection}.
3849 @end ifclear
3850
3851 @item --preprocessor @var{program}
3852 When @command{windres} reads an @code{rc} file, it runs it through the C
3853 preprocessor first. This option may be used to specify the preprocessor
3854 to use, including any leading arguments. The default preprocessor
3855 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3856
3857 @item --preprocessor-arg @var{option}
3858 When @command{windres} reads an @code{rc} file, it runs it through
3859 the C preprocessor first. This option may be used to specify additional
3860 text to be passed to preprocessor on its command line.
3861 This option can be used multiple times to add multiple options to the
3862 preprocessor command line.
3863
3864 @item -I @var{directory}
3865 @itemx --include-dir @var{directory}
3866 Specify an include directory to use when reading an @code{rc} file.
3867 @command{windres} will pass this to the preprocessor as an @option{-I}
3868 option. @command{windres} will also search this directory when looking for
3869 files named in the @code{rc} file. If the argument passed to this command
3870 matches any of the supported @var{formats} (as described in the @option{-J}
3871 option), it will issue a deprecation warning, and behave just like the
3872 @option{-J} option. New programs should not use this behaviour. If a
3873 directory happens to match a @var{format}, simple prefix it with @samp{./}
3874 to disable the backward compatibility.
3875
3876 @item -D @var{target}
3877 @itemx --define @var{sym}[=@var{val}]
3878 Specify a @option{-D} option to pass to the preprocessor when reading an
3879 @code{rc} file.
3880
3881 @item -U @var{target}
3882 @itemx --undefine @var{sym}
3883 Specify a @option{-U} option to pass to the preprocessor when reading an
3884 @code{rc} file.
3885
3886 @item -r
3887 Ignored for compatibility with rc.
3888
3889 @item -v
3890 Enable verbose mode. This tells you what the preprocessor is if you
3891 didn't specify one.
3892
3893 @item -c @var{val}
3894 @item --codepage @var{val}
3895 Specify the default codepage to use when reading an @code{rc} file.
3896 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3897 codepage code. The valid range is from zero up to 0xffff, but the
3898 validity of the codepage is host and configuration dependent.
3899
3900 @item -l @var{val}
3901 @item --language @var{val}
3902 Specify the default language to use when reading an @code{rc} file.
3903 @var{val} should be a hexadecimal language code. The low eight bits are
3904 the language, and the high eight bits are the sublanguage.
3905
3906 @item --use-temp-file
3907 Use a temporary file to instead of using popen to read the output of
3908 the preprocessor. Use this option if the popen implementation is buggy
3909 on the host (eg., certain non-English language versions of Windows 95 and
3910 Windows 98 are known to have buggy popen where the output will instead
3911 go the console).
3912
3913 @item --no-use-temp-file
3914 Use popen, not a temporary file, to read the output of the preprocessor.
3915 This is the default behaviour.
3916
3917 @item -h
3918 @item --help
3919 Prints a usage summary.
3920
3921 @item -V
3922 @item --version
3923 Prints the version number for @command{windres}.
3924
3925 @item --yydebug
3926 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3927 this will turn on parser debugging.
3928 @end table
3929
3930 @c man end
3931
3932 @ignore
3933 @c man begin SEEALSO windres
3934 the Info entries for @file{binutils}.
3935 @c man end
3936 @end ignore
3937
3938 @node dlltool
3939 @chapter dlltool
3940 @cindex DLL
3941 @kindex dlltool
3942
3943 @command{dlltool} is used to create the files needed to create dynamic
3944 link libraries (DLLs) on systems which understand PE format image
3945 files such as Windows. A DLL contains an export table which contains
3946 information that the runtime loader needs to resolve references from a
3947 referencing program.
3948
3949 The export table is generated by this program by reading in a
3950 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3951 will be in the DLL. A @file{.o} file can contain information in
3952 special @samp{.drectve} sections with export information.
3953
3954 @quotation
3955 @emph{Note:} @command{dlltool} is not always built as part of the
3956 binary utilities, since it is only useful for those targets which
3957 support DLLs.
3958 @end quotation
3959
3960 @c man title dlltool Create files needed to build and use DLLs.
3961
3962 @smallexample
3963 @c man begin SYNOPSIS dlltool
3964 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3965 [@option{-b}|@option{--base-file} @var{base-file-name}]
3966 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3967 [@option{-z}|@option{--output-def} @var{def-file-name}]
3968 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3969 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
3970 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3971 [@option{--exclude-symbols} @var{list}]
3972 [@option{--no-default-excludes}]
3973 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3974 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3975 [@option{-a}|@option{--add-indirect}]
3976 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3977 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3978 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3979 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
3980 [@option{--use-nul-prefixed-import-tables}]
3981 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
3982 [@option{-i}|@option{--interwork}]
3983 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3984 [@option{-v}|@option{--verbose}]
3985 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3986 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
3987 [object-file @dots{}]
3988 @c man end
3989 @end smallexample
3990
3991 @c man begin DESCRIPTION dlltool
3992
3993 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3994 @option{-b} options as well as object files specified on the command
3995 line. It then processes these inputs and if the @option{-e} option has
3996 been specified it creates a exports file. If the @option{-l} option
3997 has been specified it creates a library file and if the @option{-z} option
3998 has been specified it creates a def file. Any or all of the @option{-e},
3999 @option{-l} and @option{-z} options can be present in one invocation of
4000 dlltool.
4001
4002 When creating a DLL, along with the source for the DLL, it is necessary
4003 to have three other files. @command{dlltool} can help with the creation of
4004 these files.
4005
4006 The first file is a @file{.def} file which specifies which functions are
4007 exported from the DLL, which functions the DLL imports, and so on. This
4008 is a text file and can be created by hand, or @command{dlltool} can be used
4009 to create it using the @option{-z} option. In this case @command{dlltool}
4010 will scan the object files specified on its command line looking for
4011 those functions which have been specially marked as being exported and
4012 put entries for them in the @file{.def} file it creates.
4013
4014 In order to mark a function as being exported from a DLL, it needs to
4015 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4016 section of the object file. This can be done in C by using the
4017 asm() operator:
4018
4019 @smallexample
4020 asm (".section .drectve");
4021 asm (".ascii \"-export:my_func\"");
4022
4023 int my_func (void) @{ @dots{} @}
4024 @end smallexample
4025
4026 The second file needed for DLL creation is an exports file. This file
4027 is linked with the object files that make up the body of the DLL and it
4028 handles the interface between the DLL and the outside world. This is a
4029 binary file and it can be created by giving the @option{-e} option to
4030 @command{dlltool} when it is creating or reading in a @file{.def} file.
4031
4032 The third file needed for DLL creation is the library file that programs
4033 will link with in order to access the functions in the DLL (an `import
4034 library'). This file can be created by giving the @option{-l} option to
4035 dlltool when it is creating or reading in a @file{.def} file.
4036
4037 If the @option{-y} option is specified, dlltool generates a delay-import
4038 library that can be used instead of the normal import library to allow
4039 a program to link to the dll only as soon as an imported function is
4040 called for the first time. The resulting executable will need to be
4041 linked to the static delayimp library containing __delayLoadHelper2(),
4042 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4043
4044 @command{dlltool} builds the library file by hand, but it builds the
4045 exports file by creating temporary files containing assembler statements
4046 and then assembling these. The @option{-S} command line option can be
4047 used to specify the path to the assembler that dlltool will use,
4048 and the @option{-f} option can be used to pass specific flags to that
4049 assembler. The @option{-n} can be used to prevent dlltool from deleting
4050 these temporary assembler files when it is done, and if @option{-n} is
4051 specified twice then this will prevent dlltool from deleting the
4052 temporary object files it used to build the library.
4053
4054 Here is an example of creating a DLL from a source file @samp{dll.c} and
4055 also creating a program (from an object file called @samp{program.o})
4056 that uses that DLL:
4057
4058 @smallexample
4059 gcc -c dll.c
4060 dlltool -e exports.o -l dll.lib dll.o
4061 gcc dll.o exports.o -o dll.dll
4062 gcc program.o dll.lib -o program
4063 @end smallexample
4064
4065
4066 @command{dlltool} may also be used to query an existing import library
4067 to determine the name of the DLL to which it is associated. See the
4068 description of the @option{-I} or @option{--identify} option.
4069
4070 @c man end
4071
4072 @c man begin OPTIONS dlltool
4073
4074 The command line options have the following meanings:
4075
4076 @table @env
4077
4078 @item -d @var{filename}
4079 @itemx --input-def @var{filename}
4080 @cindex input .def file
4081 Specifies the name of a @file{.def} file to be read in and processed.
4082
4083 @item -b @var{filename}
4084 @itemx --base-file @var{filename}
4085 @cindex base files
4086 Specifies the name of a base file to be read in and processed. The
4087 contents of this file will be added to the relocation section in the
4088 exports file generated by dlltool.
4089
4090 @item -e @var{filename}
4091 @itemx --output-exp @var{filename}
4092 Specifies the name of the export file to be created by dlltool.
4093
4094 @item -z @var{filename}
4095 @itemx --output-def @var{filename}
4096 Specifies the name of the @file{.def} file to be created by dlltool.
4097
4098 @item -l @var{filename}
4099 @itemx --output-lib @var{filename}
4100 Specifies the name of the library file to be created by dlltool.
4101
4102 @item -y @var{filename}
4103 @itemx --output-delaylib @var{filename}
4104 Specifies the name of the delay-import library file to be created by dlltool.
4105
4106 @item --export-all-symbols
4107 Treat all global and weak defined symbols found in the input object
4108 files as symbols to be exported. There is a small list of symbols which
4109 are not exported by default; see the @option{--no-default-excludes}
4110 option. You may add to the list of symbols to not export by using the
4111 @option{--exclude-symbols} option.
4112
4113 @item --no-export-all-symbols
4114 Only export symbols explicitly listed in an input @file{.def} file or in
4115 @samp{.drectve} sections in the input object files. This is the default
4116 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4117 attributes in the source code.
4118
4119 @item --exclude-symbols @var{list}
4120 Do not export the symbols in @var{list}. This is a list of symbol names
4121 separated by comma or colon characters. The symbol names should not
4122 contain a leading underscore. This is only meaningful when
4123 @option{--export-all-symbols} is used.
4124
4125 @item --no-default-excludes
4126 When @option{--export-all-symbols} is used, it will by default avoid
4127 exporting certain special symbols. The current list of symbols to avoid
4128 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4129 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4130 to go ahead and export these special symbols. This is only meaningful
4131 when @option{--export-all-symbols} is used.
4132
4133 @item -S @var{path}
4134 @itemx --as @var{path}
4135 Specifies the path, including the filename, of the assembler to be used
4136 to create the exports file.
4137
4138 @item -f @var{options}
4139 @itemx --as-flags @var{options}
4140 Specifies any specific command line options to be passed to the
4141 assembler when building the exports file. This option will work even if
4142 the @option{-S} option is not used. This option only takes one argument,
4143 and if it occurs more than once on the command line, then later
4144 occurrences will override earlier occurrences. So if it is necessary to
4145 pass multiple options to the assembler they should be enclosed in
4146 double quotes.
4147
4148 @item -D @var{name}
4149 @itemx --dll-name @var{name}
4150 Specifies the name to be stored in the @file{.def} file as the name of
4151 the DLL when the @option{-e} option is used. If this option is not
4152 present, then the filename given to the @option{-e} option will be
4153 used as the name of the DLL.
4154
4155 @item -m @var{machine}
4156 @itemx -machine @var{machine}
4157 Specifies the type of machine for which the library file should be
4158 built. @command{dlltool} has a built in default type, depending upon how
4159 it was created, but this option can be used to override that. This is
4160 normally only useful when creating DLLs for an ARM processor, when the
4161 contents of the DLL are actually encode using Thumb instructions.
4162
4163 @item -a
4164 @itemx --add-indirect
4165 Specifies that when @command{dlltool} is creating the exports file it
4166 should add a section which allows the exported functions to be
4167 referenced without using the import library. Whatever the hell that
4168 means!
4169
4170 @item -U
4171 @itemx --add-underscore
4172 Specifies that when @command{dlltool} is creating the exports file it
4173 should prepend an underscore to the names of @emph{all} exported symbols.
4174
4175 @item --no-leading-underscore
4176 @item --leading-underscore
4177 Specifies whether standard symbol should be forced to be prefixed, or
4178 not.
4179
4180 @item --add-stdcall-underscore
4181 Specifies that when @command{dlltool} is creating the exports file it
4182 should prepend an underscore to the names of exported @emph{stdcall}
4183 functions. Variable names and non-stdcall function names are not modified.
4184 This option is useful when creating GNU-compatible import libs for third
4185 party DLLs that were built with MS-Windows tools.
4186
4187 @item -k
4188 @itemx --kill-at
4189 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4190 of stdcall functions that will be imported from the DLL. This is
4191 useful when creating an import library for a DLL which exports stdcall
4192 functions but without the usual @samp{@@<number>} symbol name suffix.
4193
4194 This does not change the naming of symbols provided by the import library
4195 to programs linked against it, but only the entries in the import table
4196 (ie the .idata section).
4197
4198 @item -A
4199 @itemx --add-stdcall-alias
4200 Specifies that when @command{dlltool} is creating the exports file it
4201 should add aliases for stdcall symbols without @samp{@@ <number>}
4202 in addition to the symbols with @samp{@@ <number>}.
4203
4204 @item -p
4205 @itemx --ext-prefix-alias @var{prefix}
4206 Causes @command{dlltool} to create external aliases for all DLL
4207 imports with the specified prefix. The aliases are created for both
4208 external and import symbols with no leading underscore.
4209
4210 @item -x
4211 @itemx --no-idata4
4212 Specifies that when @command{dlltool} is creating the exports and library
4213 files it should omit the @code{.idata4} section. This is for compatibility
4214 with certain operating systems.
4215
4216 @item --use-nul-prefixed-import-tables
4217 Specifies that when @command{dlltool} is creating the exports and library
4218 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4219 element. This emulates old gnu import library generation of
4220 @code{dlltool}. By default this option is turned off.
4221
4222 @item -c
4223 @itemx --no-idata5
4224 Specifies that when @command{dlltool} is creating the exports and library
4225 files it should omit the @code{.idata5} section. This is for compatibility
4226 with certain operating systems.
4227
4228 @item -I @var{filename}
4229 @itemx --identify @var{filename}
4230 Specifies that @command{dlltool} should inspect the import library
4231 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4232 of the associated DLL(s). This can be performed in addition to any
4233 other operations indicated by the other options and arguments.
4234 @command{dlltool} fails if the import library does not exist or is not
4235 actually an import library. See also @option{--identify-strict}.
4236
4237 @item --identify-strict
4238 Modifies the behavior of the @option{--identify} option, such
4239 that an error is reported if @var{filename} is associated with
4240 more than one DLL.
4241
4242 @item -i
4243 @itemx --interwork
4244 Specifies that @command{dlltool} should mark the objects in the library
4245 file and exports file that it produces as supporting interworking
4246 between ARM and Thumb code.
4247
4248 @item -n
4249 @itemx --nodelete
4250 Makes @command{dlltool} preserve the temporary assembler files it used to
4251 create the exports file. If this option is repeated then dlltool will
4252 also preserve the temporary object files it uses to create the library
4253 file.
4254
4255 @item -t @var{prefix}
4256 @itemx --temp-prefix @var{prefix}
4257 Makes @command{dlltool} use @var{prefix} when constructing the names of
4258 temporary assembler and object files. By default, the temp file prefix
4259 is generated from the pid.
4260
4261 @item -v
4262 @itemx --verbose
4263 Make dlltool describe what it is doing.
4264
4265 @item -h
4266 @itemx --help
4267 Displays a list of command line options and then exits.
4268
4269 @item -V
4270 @itemx --version
4271 Displays dlltool's version number and then exits.
4272
4273 @end table
4274
4275 @c man end
4276
4277 @menu
4278 * def file format:: The format of the dlltool @file{.def} file
4279 @end menu
4280
4281 @node def file format
4282 @section The format of the @command{dlltool} @file{.def} file
4283
4284 A @file{.def} file contains any number of the following commands:
4285
4286 @table @asis
4287
4288 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4289 The result is going to be named @var{name}@code{.exe}.
4290
4291 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4292 The result is going to be named @var{name}@code{.dll}.
4293 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4294 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4295 details).
4296
4297 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4298 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4299 Declares @var{name1} as an exported symbol from the DLL, with optional
4300 ordinal number @var{integer}, or declares @var{name1} as an alias
4301 (forward) of the function @var{external-name} in the DLL.
4302 If @var{its_name} is specified, this name is used as string in export table.
4303 @var{module-name}.
4304 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4305 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4306 If you want to use LIBRARY as name then you need to quote it.
4307
4308 @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{]} *}
4309 Declares that @var{external-name} or the exported function whose
4310 ordinal number is @var{integer} is to be imported from the file
4311 @var{module-name}. If @var{internal-name} is specified then this is
4312 the name that the imported function will be referred to in the body of
4313 the DLL.
4314 If @var{its_name} is specified, this name is used as string in import table.
4315 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4316 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4317 If you want to use LIBRARY as name then you need to quote it.
4318
4319 @item @code{DESCRIPTION} @var{string}
4320 Puts @var{string} into the output @file{.exp} file in the
4321 @code{.rdata} section.
4322
4323 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4324 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4325 Generates @code{--stack} or @code{--heap}
4326 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4327 section. The linker will see this and act upon it.
4328
4329 @item @code{CODE} @var{attr} @code{+}
4330 @item @code{DATA} @var{attr} @code{+}
4331 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4332 Generates @code{--attr} @var{section-name} @var{attr} in the output
4333 @code{.drectve} section, where @var{attr} is one of @code{READ},
4334 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4335 this and act upon it.
4336
4337 @end table
4338
4339 @ignore
4340 @c man begin SEEALSO dlltool
4341 The Info pages for @file{binutils}.
4342 @c man end
4343 @end ignore
4344
4345 @node readelf
4346 @chapter readelf
4347
4348 @cindex ELF file information
4349 @kindex readelf
4350
4351 @c man title readelf Displays information about ELF files.
4352
4353 @smallexample
4354 @c man begin SYNOPSIS readelf
4355 readelf [@option{-a}|@option{--all}]
4356 [@option{-h}|@option{--file-header}]
4357 [@option{-l}|@option{--program-headers}|@option{--segments}]
4358 [@option{-S}|@option{--section-headers}|@option{--sections}]
4359 [@option{-g}|@option{--section-groups}]
4360 [@option{-t}|@option{--section-details}]
4361 [@option{-e}|@option{--headers}]
4362 [@option{-s}|@option{--syms}|@option{--symbols}]
4363 [@option{--dyn-syms}]
4364 [@option{-n}|@option{--notes}]
4365 [@option{-r}|@option{--relocs}]
4366 [@option{-u}|@option{--unwind}]
4367 [@option{-d}|@option{--dynamic}]
4368 [@option{-V}|@option{--version-info}]
4369 [@option{-A}|@option{--arch-specific}]
4370 [@option{-D}|@option{--use-dynamic}]
4371 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4372 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4373 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4374 [@option{-z}|@option{--decompress}]
4375 [@option{-c}|@option{--archive-index}]
4376 [@option{-w[lLiaprmfFsoRt]}|
4377 @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]]
4378 [@option{--dwarf-depth=@var{n}}]
4379 [@option{--dwarf-start=@var{n}}]
4380 [@option{-I}|@option{--histogram}]
4381 [@option{-v}|@option{--version}]
4382 [@option{-W}|@option{--wide}]
4383 [@option{-H}|@option{--help}]
4384 @var{elffile}@dots{}
4385 @c man end
4386 @end smallexample
4387
4388 @c man begin DESCRIPTION readelf
4389
4390 @command{readelf} displays information about one or more ELF format object
4391 files. The options control what particular information to display.
4392
4393 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4394 64-bit ELF files are supported, as are archives containing ELF files.
4395
4396 This program performs a similar function to @command{objdump} but it
4397 goes into more detail and it exists independently of the @sc{bfd}
4398 library, so if there is a bug in @sc{bfd} then readelf will not be
4399 affected.
4400
4401 @c man end
4402
4403 @c man begin OPTIONS readelf
4404
4405 The long and short forms of options, shown here as alternatives, are
4406 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4407 given.
4408
4409 @table @env
4410 @item -a
4411 @itemx --all
4412 Equivalent to specifying @option{--file-header},
4413 @option{--program-headers}, @option{--sections}, @option{--symbols},
4414 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4415 @option{--version-info}.
4416
4417 @item -h
4418 @itemx --file-header
4419 @cindex ELF file header information
4420 Displays the information contained in the ELF header at the start of the
4421 file.
4422
4423 @item -l
4424 @itemx --program-headers
4425 @itemx --segments
4426 @cindex ELF program header information
4427 @cindex ELF segment information
4428 Displays the information contained in the file's segment headers, if it
4429 has any.
4430
4431 @item -S
4432 @itemx --sections
4433 @itemx --section-headers
4434 @cindex ELF section information
4435 Displays the information contained in the file's section headers, if it
4436 has any.
4437
4438 @item -g
4439 @itemx --section-groups
4440 @cindex ELF section group information
4441 Displays the information contained in the file's section groups, if it
4442 has any.
4443
4444 @item -t
4445 @itemx --section-details
4446 @cindex ELF section information
4447 Displays the detailed section information. Implies @option{-S}.
4448
4449 @item -s
4450 @itemx --symbols
4451 @itemx --syms
4452 @cindex ELF symbol table information
4453 Displays the entries in symbol table section of the file, if it has one.
4454
4455 @item --dyn-syms
4456 @cindex ELF dynamic symbol table information
4457 Displays the entries in dynamic symbol table section of the file, if it
4458 has one.
4459
4460 @item -e
4461 @itemx --headers
4462 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4463
4464 @item -n
4465 @itemx --notes
4466 @cindex ELF notes
4467 Displays the contents of the NOTE segments and/or sections, if any.
4468
4469 @item -r
4470 @itemx --relocs
4471 @cindex ELF reloc information
4472 Displays the contents of the file's relocation section, if it has one.
4473
4474 @item -u
4475 @itemx --unwind
4476 @cindex unwind information
4477 Displays the contents of the file's unwind section, if it has one. Only
4478 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4479 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4480
4481 @item -d
4482 @itemx --dynamic
4483 @cindex ELF dynamic section information
4484 Displays the contents of the file's dynamic section, if it has one.
4485
4486 @item -V
4487 @itemx --version-info
4488 @cindex ELF version sections information
4489 Displays the contents of the version sections in the file, it they
4490 exist.
4491
4492 @item -A
4493 @itemx --arch-specific
4494 Displays architecture-specific information in the file, if there
4495 is any.
4496
4497 @item -D
4498 @itemx --use-dynamic
4499 When displaying symbols, this option makes @command{readelf} use the
4500 symbol hash tables in the file's dynamic section, rather than the
4501 symbol table sections.
4502
4503 @item -x <number or name>
4504 @itemx --hex-dump=<number or name>
4505 Displays the contents of the indicated section as a hexadecimal bytes.
4506 A number identifies a particular section by index in the section table;
4507 any other string identifies all sections with that name in the object file.
4508
4509 @item -R <number or name>
4510 @itemx --relocated-dump=<number or name>
4511 Displays the contents of the indicated section as a hexadecimal
4512 bytes. A number identifies a particular section by index in the
4513 section table; any other string identifies all sections with that name
4514 in the object file. The contents of the section will be relocated
4515 before they are displayed.
4516
4517 @item -p <number or name>
4518 @itemx --string-dump=<number or name>
4519 Displays the contents of the indicated section as printable strings.
4520 A number identifies a particular section by index in the section table;
4521 any other string identifies all sections with that name in the object file.
4522
4523 @item -z
4524 @itemx --decompress
4525 Requests that the section(s) being dumped by @option{x}, @option{R} or
4526 @option{p} options are decompressed before being displayed. If the
4527 section(s) are not compressed then they are displayed as is.
4528
4529 @item -c
4530 @itemx --archive-index
4531 @cindex Archive file symbol index information
4532 Displays the file symbol index information contained in the header part
4533 of binary archives. Performs the same function as the @option{t}
4534 command to @command{ar}, but without using the BFD library. @xref{ar}.
4535
4536 @item -w[lLiaprmfFsoRt]
4537 @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]
4538 Displays the contents of the debug sections in the file, if any are
4539 present. If one of the optional letters or words follows the switch
4540 then only data found in those specific sections will be dumped.
4541
4542 Note that there is no single letter option to display the content of
4543 trace sections or .gdb_index.
4544
4545 Note: the @option{=decodedline} option will display the interpreted
4546 contents of a .debug_line section whereas the @option{=rawline} option
4547 dumps the contents in a raw format.
4548
4549 Note: the @option{=frames-interp} option will display the interpreted
4550 contents of a .debug_frame section whereas the @option{=frames} option
4551 dumps the contents in a raw format.
4552
4553 Note: the output from the @option{=info} option can also be affected
4554 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4555
4556 @item --dwarf-depth=@var{n}
4557 Limit the dump of the @code{.debug_info} section to @var{n} children.
4558 This is only useful with @option{--debug-dump=info}. The default is
4559 to print all DIEs; the special value 0 for @var{n} will also have this
4560 effect.
4561
4562 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4563 levels will not be printed. The range for @var{n} is zero-based.
4564
4565 @item --dwarf-start=@var{n}
4566 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4567 useful with @option{--debug-dump=info}.
4568
4569 If specified, this option will suppress printing of any header
4570 information and all DIEs before the DIE numbered @var{n}. Only
4571 siblings and children of the specified DIE will be printed.
4572
4573 This can be used in conjunction with @option{--dwarf-depth}.
4574
4575 @item -I
4576 @itemx --histogram
4577 Display a histogram of bucket list lengths when displaying the contents
4578 of the symbol tables.
4579
4580 @item -v
4581 @itemx --version
4582 Display the version number of readelf.
4583
4584 @item -W
4585 @itemx --wide
4586 Don't break output lines to fit into 80 columns. By default
4587 @command{readelf} breaks section header and segment listing lines for
4588 64-bit ELF files, so that they fit into 80 columns. This option causes
4589 @command{readelf} to print each section header resp. each segment one a
4590 single line, which is far more readable on terminals wider than 80 columns.
4591
4592 @item -H
4593 @itemx --help
4594 Display the command line options understood by @command{readelf}.
4595
4596 @end table
4597
4598 @c man end
4599
4600 @ignore
4601 @c man begin SEEALSO readelf
4602 objdump(1), and the Info entries for @file{binutils}.
4603 @c man end
4604 @end ignore
4605
4606 @node elfedit
4607 @chapter elfedit
4608
4609 @cindex Update ELF header
4610 @kindex elfedit
4611
4612 @c man title elfedit Update the ELF header of ELF files.
4613
4614 @smallexample
4615 @c man begin SYNOPSIS elfedit
4616 elfedit [@option{--input-mach=}@var{machine}]
4617 [@option{--input-type=}@var{type}]
4618 [@option{--input-osabi=}@var{osabi}]
4619 @option{--output-mach=}@var{machine}
4620 @option{--output-type=}@var{type}
4621 @option{--output-osabi=}@var{osabi}
4622 [@option{-v}|@option{--version}]
4623 [@option{-h}|@option{--help}]
4624 @var{elffile}@dots{}
4625 @c man end
4626 @end smallexample
4627
4628 @c man begin DESCRIPTION elfedit
4629
4630 @command{elfedit} updates the ELF header of ELF files which have
4631 the matching ELF machine and file types. The options control how and
4632 which fields in the ELF header should be updated.
4633
4634 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4635 64-bit ELF files are supported, as are archives containing ELF files.
4636 @c man end
4637
4638 @c man begin OPTIONS elfedit
4639
4640 The long and short forms of options, shown here as alternatives, are
4641 equivalent. At least one of the @option{--output-mach},
4642 @option{--output-type} and @option{--output-osabi} options must be given.
4643
4644 @table @env
4645
4646 @item --input-mach=@var{machine}
4647 Set the matching input ELF machine type to @var{machine}. If
4648 @option{--input-mach} isn't specified, it will match any ELF
4649 machine types.
4650
4651 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4652 @var{K1OM} and @var{x86-64}.
4653
4654 @item --output-mach=@var{machine}
4655 Change the ELF machine type in the ELF header to @var{machine}. The
4656 supported ELF machine types are the same as @option{--input-mach}.
4657
4658 @item --input-type=@var{type}
4659 Set the matching input ELF file type to @var{type}. If
4660 @option{--input-type} isn't specified, it will match any ELF file types.
4661
4662 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4663
4664 @item --output-type=@var{type}
4665 Change the ELF file type in the ELF header to @var{type}. The
4666 supported ELF types are the same as @option{--input-type}.
4667
4668 @item --input-osabi=@var{osabi}
4669 Set the matching input ELF file OSABI to @var{osabi}. If
4670 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4671
4672 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4673 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4674 @var{Solaris}, @var{AIX}, @var{Irix},
4675 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4676 @var{NSK}, @var{AROS} and @var{FenixOS}.
4677
4678 @item --output-osabi=@var{osabi}
4679 Change the ELF OSABI in the ELF header to @var{osabi}. The
4680 supported ELF OSABI are the same as @option{--input-osabi}.
4681
4682 @item -v
4683 @itemx --version
4684 Display the version number of @command{elfedit}.
4685
4686 @item -h
4687 @itemx --help
4688 Display the command line options understood by @command{elfedit}.
4689
4690 @end table
4691
4692 @c man end
4693
4694 @ignore
4695 @c man begin SEEALSO elfedit
4696 readelf(1), and the Info entries for @file{binutils}.
4697 @c man end
4698 @end ignore
4699
4700 @node Common Options
4701 @chapter Common Options
4702
4703 The following command-line options are supported by all of the
4704 programs described in this manual.
4705
4706 @c man begin OPTIONS
4707 @table @env
4708 @include at-file.texi
4709 @c man end
4710
4711 @item --help
4712 Display the command-line options supported by the program.
4713
4714 @item --version
4715 Display the version number of the program.
4716
4717 @c man begin OPTIONS
4718 @end table
4719 @c man end
4720
4721 @node Selecting the Target System
4722 @chapter Selecting the Target System
4723
4724 You can specify two aspects of the target system to the @sc{gnu}
4725 binary file utilities, each in several ways:
4726
4727 @itemize @bullet
4728 @item
4729 the target
4730
4731 @item
4732 the architecture
4733 @end itemize
4734
4735 In the following summaries, the lists of ways to specify values are in
4736 order of decreasing precedence. The ways listed first override those
4737 listed later.
4738
4739 The commands to list valid values only list the values for which the
4740 programs you are running were configured. If they were configured with
4741 @option{--enable-targets=all}, the commands list most of the available
4742 values, but a few are left out; not all targets can be configured in at
4743 once because some of them can only be configured @dfn{native} (on hosts
4744 with the same type as the target system).
4745
4746 @menu
4747 * Target Selection::
4748 * Architecture Selection::
4749 @end menu
4750
4751 @node Target Selection
4752 @section Target Selection
4753
4754 A @dfn{target} is an object file format. A given target may be
4755 supported for multiple architectures (@pxref{Architecture Selection}).
4756 A target selection may also have variations for different operating
4757 systems or architectures.
4758
4759 The command to list valid target values is @samp{objdump -i}
4760 (the first column of output contains the relevant information).
4761
4762 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4763 @samp{a.out-sunos-big}.
4764
4765 You can also specify a target using a configuration triplet. This is
4766 the same sort of name that is passed to @file{configure} to specify a
4767 target. When you use a configuration triplet as an argument, it must be
4768 fully canonicalized. You can see the canonical version of a triplet by
4769 running the shell script @file{config.sub} which is included with the
4770 sources.
4771
4772 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4773 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4774
4775 @subheading @command{objdump} Target
4776
4777 Ways to specify:
4778
4779 @enumerate
4780 @item
4781 command line option: @option{-b} or @option{--target}
4782
4783 @item
4784 environment variable @code{GNUTARGET}
4785
4786 @item
4787 deduced from the input file
4788 @end enumerate
4789
4790 @subheading @command{objcopy} and @command{strip} Input Target
4791
4792 Ways to specify:
4793
4794 @enumerate
4795 @item
4796 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4797
4798 @item
4799 environment variable @code{GNUTARGET}
4800
4801 @item
4802 deduced from the input file
4803 @end enumerate
4804
4805 @subheading @command{objcopy} and @command{strip} Output Target
4806
4807 Ways to specify:
4808
4809 @enumerate
4810 @item
4811 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4812
4813 @item
4814 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4815
4816 @item
4817 environment variable @code{GNUTARGET}
4818
4819 @item
4820 deduced from the input file
4821 @end enumerate
4822
4823 @subheading @command{nm}, @command{size}, and @command{strings} Target
4824
4825 Ways to specify:
4826
4827 @enumerate
4828 @item
4829 command line option: @option{--target}
4830
4831 @item
4832 environment variable @code{GNUTARGET}
4833
4834 @item
4835 deduced from the input file
4836 @end enumerate
4837
4838 @node Architecture Selection
4839 @section Architecture Selection
4840
4841 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4842 to run. Its name may contain a colon, separating the name of the
4843 processor family from the name of the particular @sc{cpu}.
4844
4845 The command to list valid architecture values is @samp{objdump -i} (the
4846 second column contains the relevant information).
4847
4848 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4849
4850 @subheading @command{objdump} Architecture
4851
4852 Ways to specify:
4853
4854 @enumerate
4855 @item
4856 command line option: @option{-m} or @option{--architecture}
4857
4858 @item
4859 deduced from the input file
4860 @end enumerate
4861
4862 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4863
4864 Ways to specify:
4865
4866 @enumerate
4867 @item
4868 deduced from the input file
4869 @end enumerate
4870
4871 @node Reporting Bugs
4872 @chapter Reporting Bugs
4873 @cindex bugs
4874 @cindex reporting bugs
4875
4876 Your bug reports play an essential role in making the binary utilities
4877 reliable.
4878
4879 Reporting a bug may help you by bringing a solution to your problem, or
4880 it may not. But in any case the principal function of a bug report is
4881 to help the entire community by making the next version of the binary
4882 utilities work better. Bug reports are your contribution to their
4883 maintenance.
4884
4885 In order for a bug report to serve its purpose, you must include the
4886 information that enables us to fix the bug.
4887
4888 @menu
4889 * Bug Criteria:: Have you found a bug?
4890 * Bug Reporting:: How to report bugs
4891 @end menu
4892
4893 @node Bug Criteria
4894 @section Have You Found a Bug?
4895 @cindex bug criteria
4896
4897 If you are not sure whether you have found a bug, here are some guidelines:
4898
4899 @itemize @bullet
4900 @cindex fatal signal
4901 @cindex crash
4902 @item
4903 If a binary utility gets a fatal signal, for any input whatever, that is
4904 a bug. Reliable utilities never crash.
4905
4906 @cindex error on valid input
4907 @item
4908 If a binary utility produces an error message for valid input, that is a
4909 bug.
4910
4911 @item
4912 If you are an experienced user of binary utilities, your suggestions for
4913 improvement are welcome in any case.
4914 @end itemize
4915
4916 @node Bug Reporting
4917 @section How to Report Bugs
4918 @cindex bug reports
4919 @cindex bugs, reporting
4920
4921 A number of companies and individuals offer support for @sc{gnu}
4922 products. If you obtained the binary utilities from a support
4923 organization, we recommend you contact that organization first.
4924
4925 You can find contact information for many support companies and
4926 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4927 distribution.
4928
4929 @ifset BUGURL
4930 In any event, we also recommend that you send bug reports for the binary
4931 utilities to @value{BUGURL}.
4932 @end ifset
4933
4934 The fundamental principle of reporting bugs usefully is this:
4935 @strong{report all the facts}. If you are not sure whether to state a
4936 fact or leave it out, state it!
4937
4938 Often people omit facts because they think they know what causes the
4939 problem and assume that some details do not matter. Thus, you might
4940 assume that the name of a file you use in an example does not matter.
4941 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4942 a stray memory reference which happens to fetch from the location where
4943 that pathname is stored in memory; perhaps, if the pathname were
4944 different, the contents of that location would fool the utility into
4945 doing the right thing despite the bug. Play it safe and give a
4946 specific, complete example. That is the easiest thing for you to do,
4947 and the most helpful.
4948
4949 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4950 it is new to us. Therefore, always write your bug reports on the assumption
4951 that the bug has not been reported previously.
4952
4953 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4954 bell?'' This cannot help us fix a bug, so it is basically useless. We
4955 respond by asking for enough details to enable us to investigate.
4956 You might as well expedite matters by sending them to begin with.
4957
4958 To enable us to fix the bug, you should include all these things:
4959
4960 @itemize @bullet
4961 @item
4962 The version of the utility. Each utility announces it if you start it
4963 with the @option{--version} argument.
4964
4965 Without this, we will not know whether there is any point in looking for
4966 the bug in the current version of the binary utilities.
4967
4968 @item
4969 Any patches you may have applied to the source, including any patches
4970 made to the @code{BFD} library.
4971
4972 @item
4973 The type of machine you are using, and the operating system name and
4974 version number.
4975
4976 @item
4977 What compiler (and its version) was used to compile the utilities---e.g.
4978 ``@code{gcc-2.7}''.
4979
4980 @item
4981 The command arguments you gave the utility to observe the bug. To
4982 guarantee you will not omit something important, list them all. A copy
4983 of the Makefile (or the output from make) is sufficient.
4984
4985 If we were to try to guess the arguments, we would probably guess wrong
4986 and then we might not encounter the bug.
4987
4988 @item
4989 A complete input file, or set of input files, that will reproduce the
4990 bug. If the utility is reading an object file or files, then it is
4991 generally most helpful to send the actual object files.
4992
4993 If the source files were produced exclusively using @sc{gnu} programs
4994 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4995 may be OK to send the source files rather than the object files. In
4996 this case, be sure to say exactly what version of @command{gcc}, or
4997 whatever, was used to produce the object files. Also say how
4998 @command{gcc}, or whatever, was configured.
4999
5000 @item
5001 A description of what behavior you observe that you believe is
5002 incorrect. For example, ``It gets a fatal signal.''
5003
5004 Of course, if the bug is that the utility gets a fatal signal, then we
5005 will certainly notice it. But if the bug is incorrect output, we might
5006 not notice unless it is glaringly wrong. You might as well not give us
5007 a chance to make a mistake.
5008
5009 Even if the problem you experience is a fatal signal, you should still
5010 say so explicitly. Suppose something strange is going on, such as your
5011 copy of the utility is out of sync, or you have encountered a bug in
5012 the C library on your system. (This has happened!) Your copy might
5013 crash and ours would not. If you told us to expect a crash, then when
5014 ours fails to crash, we would know that the bug was not happening for
5015 us. If you had not told us to expect a crash, then we would not be able
5016 to draw any conclusion from our observations.
5017
5018 @item
5019 If you wish to suggest changes to the source, send us context diffs, as
5020 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5021 option. Always send diffs from the old file to the new file. If you
5022 wish to discuss something in the @command{ld} source, refer to it by
5023 context, not by line number.
5024
5025 The line numbers in our development sources will not match those in your
5026 sources. Your line numbers would convey no useful information to us.
5027 @end itemize
5028
5029 Here are some things that are not necessary:
5030
5031 @itemize @bullet
5032 @item
5033 A description of the envelope of the bug.
5034
5035 Often people who encounter a bug spend a lot of time investigating
5036 which changes to the input file will make the bug go away and which
5037 changes will not affect it.
5038
5039 This is often time consuming and not very useful, because the way we
5040 will find the bug is by running a single example under the debugger
5041 with breakpoints, not by pure deduction from a series of examples.
5042 We recommend that you save your time for something else.
5043
5044 Of course, if you can find a simpler example to report @emph{instead}
5045 of the original one, that is a convenience for us. Errors in the
5046 output will be easier to spot, running under the debugger will take
5047 less time, and so on.
5048
5049 However, simplification is not vital; if you do not want to do this,
5050 report the bug anyway and send us the entire test case you used.
5051
5052 @item
5053 A patch for the bug.
5054
5055 A patch for the bug does help us if it is a good one. But do not omit
5056 the necessary information, such as the test case, on the assumption that
5057 a patch is all we need. We might see problems with your patch and decide
5058 to fix the problem another way, or we might not understand it at all.
5059
5060 Sometimes with programs as complicated as the binary utilities it is
5061 very hard to construct an example that will make the program follow a
5062 certain path through the code. If you do not send us the example, we
5063 will not be able to construct one, so we will not be able to verify that
5064 the bug is fixed.
5065
5066 And if we cannot understand what bug you are trying to fix, or why your
5067 patch should be an improvement, we will not install it. A test case will
5068 help us to understand.
5069
5070 @item
5071 A guess about what the bug is or what it depends on.
5072
5073 Such guesses are usually wrong. Even we cannot guess right about such
5074 things without first using the debugger to find the facts.
5075 @end itemize
5076
5077 @node GNU Free Documentation License
5078 @appendix GNU Free Documentation License
5079
5080 @include fdl.texi
5081
5082 @node Binutils Index
5083 @unnumbered Binutils Index
5084
5085 @printindex cp
5086
5087 @bye
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