* emultempl/elf32.em (gld${EMULATION_NAME}_layout_sections_again):
[deliverable/binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4
5 @include config.texi
6
7 @ifinfo
8 @format
9 START-INFO-DIR-ENTRY
10 * Binutils: (binutils). The GNU binary utilities.
11 * ar: (binutils)ar. Create, modify, and extract from archives
12 * nm: (binutils)nm. List symbols from object files
13 * objcopy: (binutils)objcopy. Copy and translate object files
14 * objdump: (binutils)objdump. Display information from object files
15 * ranlib: (binutils)ranlib. Generate index to archive contents
16 * readelf: (binutils)readelf. Display the contents of ELF format files.
17 * size: (binutils)size. List section sizes and total size
18 * strings: (binutils)strings. List printable strings from files
19 * strip: (binutils)strip. Discard symbols
20 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
21 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
22 * addr2line: (binutils)addr2line. Convert addresses to file and line
23 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
24 * windres: (binutils)windres. Manipulate Windows resources
25 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
26 END-INFO-DIR-ENTRY
27 @end format
28 @end ifinfo
29
30 @ifinfo
31 @c man begin COPYRIGHT
32 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
33 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
34
35 Permission is granted to copy, distribute and/or modify this document
36 under the terms of the GNU Free Documentation License, Version 1.1
37 or any later version published by the Free Software Foundation;
38 with no Invariant Sections, with no Front-Cover Texts, and with no
39 Back-Cover Texts. A copy of the license is included in the
40 section entitled ``GNU Free Documentation License''.
41
42 @c man end
43 @ignore
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries a copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
48
49 @end ignore
50 @end ifinfo
51
52 @synindex ky cp
53 @c
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
56 @c
57 @c Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
58 @c 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
59 @c
60 @c This text may be freely distributed under the terms of the GNU
61 @c Free Documentation License.
62 @c
63
64 @setchapternewpage odd
65 @settitle @sc{gnu} Binary Utilities
66 @titlepage
67 @finalout
68 @title The @sc{gnu} Binary Utilities
69 @subtitle Version @value{VERSION}
70 @sp 1
71 @subtitle @value{UPDATED}
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
75 @page
76
77 @tex
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
80 @end tex
81
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
84 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
85
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
92
93 @end titlepage
94
95 @node Top
96 @top Introduction
97
98 @cindex version
99 This brief manual contains documentation for the @sc{gnu} binary
100 utilities (collectively version @value{VERSION}):
101
102 @iftex
103 @table @code
104 @item ar
105 Create, modify, and extract from archives
106
107 @item nm
108 List symbols from object files
109
110 @item objcopy
111 Copy and translate object files
112
113 @item objdump
114 Display information from object files
115
116 @item ranlib
117 Generate index to archive contents
118
119 @item readelf
120 Display the contents of ELF format files.
121
122 @item size
123 List file section sizes and total size
124
125 @item strings
126 List printable strings from files
127
128 @item strip
129 Discard symbols
130
131 @item c++filt
132 Demangle encoded C++ symbols (on MS-DOS, this program is named
133 @code{cxxfilt})
134
135 @item addr2line
136 Convert addresses into file names and line numbers
137
138 @item nlmconv
139 Convert object code into a Netware Loadable Module
140
141 @item windres
142 Manipulate Windows resources
143
144 @item dlltool
145 Create the files needed to build and use Dynamic Link Libraries
146 @end table
147 @end iftex
148
149 This document is distributed under the terms of the GNU Free
150 Documentation License. A copy of the license is included in the
151 section entitled "GNU Free Documentation License".
152
153 @menu
154 * ar:: Create, modify, and extract from archives
155 * nm:: List symbols from object files
156 * objcopy:: Copy and translate object files
157 * objdump:: Display information from object files
158 * ranlib:: Generate index to archive contents
159 * readelf:: Display the contents of ELF format files.
160 * size:: List section sizes and total size
161 * strings:: List printable strings from files
162 * strip:: Discard symbols
163 * c++filt:: Filter to demangle encoded C++ symbols
164 * cxxfilt: c++filt. MS-DOS name for c++filt
165 * addr2line:: Convert addresses to file and line
166 * nlmconv:: Converts object code into an NLM
167 * windres:: Manipulate Windows resources
168 * dlltool:: Create files needed to build and use DLLs
169 * Selecting The Target System:: How these utilities determine the target.
170 * Reporting Bugs:: Reporting Bugs
171 * GNU Free Documentation License:: GNU Free Documentation License
172 * Index:: Index
173 @end menu
174
175 @node ar
176 @chapter ar
177
178 @kindex ar
179 @cindex archives
180 @cindex collections of files
181
182 @c man title ar create, modify, and extract from archives
183
184 @smallexample
185 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
186 ar -M [ <mri-script ]
187 @end smallexample
188
189 @c man begin DESCRIPTION ar
190
191 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
192 archives. An @dfn{archive} is a single file holding a collection of
193 other files in a structure that makes it possible to retrieve
194 the original individual files (called @dfn{members} of the archive).
195
196 The original files' contents, mode (permissions), timestamp, owner, and
197 group are preserved in the archive, and can be restored on
198 extraction.
199
200 @cindex name length
201 @sc{gnu} @command{ar} can maintain archives whose members have names of any
202 length; however, depending on how @command{ar} is configured on your
203 system, a limit on member-name length may be imposed for compatibility
204 with archive formats maintained with other tools. If it exists, the
205 limit is often 15 characters (typical of formats related to a.out) or 16
206 characters (typical of formats related to coff).
207
208 @cindex libraries
209 @command{ar} is considered a binary utility because archives of this sort
210 are most often used as @dfn{libraries} holding commonly needed
211 subroutines.
212
213 @cindex symbol index
214 @command{ar} creates an index to the symbols defined in relocatable
215 object modules in the archive when you specify the modifier @samp{s}.
216 Once created, this index is updated in the archive whenever @command{ar}
217 makes a change to its contents (save for the @samp{q} update operation).
218 An archive with such an index speeds up linking to the library, and
219 allows routines in the library to call each other without regard to
220 their placement in the archive.
221
222 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
223 table. If an archive lacks the table, another form of @command{ar} called
224 @command{ranlib} can be used to add just the table.
225
226 @cindex compatibility, @command{ar}
227 @cindex @command{ar} compatibility
228 @sc{gnu} @command{ar} is designed to be compatible with two different
229 facilities. You can control its activity using command-line options,
230 like the different varieties of @command{ar} on Unix systems; or, if you
231 specify the single command-line option @option{-M}, you can control it
232 with a script supplied via standard input, like the MRI ``librarian''
233 program.
234
235 @c man end
236
237 @menu
238 * ar cmdline:: Controlling @command{ar} on the command line
239 * ar scripts:: Controlling @command{ar} with a script
240 @end menu
241
242 @page
243 @node ar cmdline
244 @section Controlling @command{ar} on the Command Line
245
246 @smallexample
247 @c man begin SYNOPSIS ar
248 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
249 @c man end
250 @end smallexample
251
252 @cindex Unix compatibility, @command{ar}
253 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
254 arguments to execute: one keyletter specifying the @emph{operation}
255 (optionally accompanied by other keyletters specifying
256 @emph{modifiers}), and the archive name to act on.
257
258 Most operations can also accept further @var{member} arguments,
259 specifying particular files to operate on.
260
261 @c man begin OPTIONS ar
262
263 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
264 flags @var{mod} in any order, within the first command-line argument.
265
266 If you wish, you may begin the first command-line argument with a
267 dash.
268
269 @cindex operations on archive
270 The @var{p} keyletter specifies what operation to execute; it may be
271 any of the following, but you must specify only one of them:
272
273 @table @samp
274 @item d
275 @cindex deleting from archive
276 @emph{Delete} modules from the archive. Specify the names of modules to
277 be deleted as @var{member}@dots{}; the archive is untouched if you
278 specify no files to delete.
279
280 If you specify the @samp{v} modifier, @command{ar} lists each module
281 as it is deleted.
282
283 @item m
284 @cindex moving in archive
285 Use this operation to @emph{move} members in an archive.
286
287 The ordering of members in an archive can make a difference in how
288 programs are linked using the library, if a symbol is defined in more
289 than one member.
290
291 If no modifiers are used with @code{m}, any members you name in the
292 @var{member} arguments are moved to the @emph{end} of the archive;
293 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
294 specified place instead.
295
296 @item p
297 @cindex printing from archive
298 @emph{Print} the specified members of the archive, to the standard
299 output file. If the @samp{v} modifier is specified, show the member
300 name before copying its contents to standard output.
301
302 If you specify no @var{member} arguments, all the files in the archive are
303 printed.
304
305 @item q
306 @cindex quick append to archive
307 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
308 @var{archive}, without checking for replacement.
309
310 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
311 operation; new members are always placed at the end of the archive.
312
313 The modifier @samp{v} makes @command{ar} list each file as it is appended.
314
315 Since the point of this operation is speed, the archive's symbol table
316 index is not updated, even if it already existed; you can use @samp{ar s} or
317 @command{ranlib} explicitly to update the symbol table index.
318
319 However, too many different systems assume quick append rebuilds the
320 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
321
322 @item r
323 @cindex replacement in archive
324 Insert the files @var{member}@dots{} into @var{archive} (with
325 @emph{replacement}). This operation differs from @samp{q} in that any
326 previously existing members are deleted if their names match those being
327 added.
328
329 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
330 displays an error message, and leaves undisturbed any existing members
331 of the archive matching that name.
332
333 By default, new members are added at the end of the file; but you may
334 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
335 placement relative to some existing member.
336
337 The modifier @samp{v} used with this operation elicits a line of
338 output for each file inserted, along with one of the letters @samp{a} or
339 @samp{r} to indicate whether the file was appended (no old member
340 deleted) or replaced.
341
342 @item t
343 @cindex contents of archive
344 Display a @emph{table} listing the contents of @var{archive}, or those
345 of the files listed in @var{member}@dots{} that are present in the
346 archive. Normally only the member name is shown; if you also want to
347 see the modes (permissions), timestamp, owner, group, and size, you can
348 request that by also specifying the @samp{v} modifier.
349
350 If you do not specify a @var{member}, all files in the archive
351 are listed.
352
353 @cindex repeated names in archive
354 @cindex name duplication in archive
355 If there is more than one file with the same name (say, @samp{fie}) in
356 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
357 first instance; to see them all, you must ask for a complete
358 listing---in our example, @samp{ar t b.a}.
359 @c WRS only; per Gumby, this is implementation-dependent, and in a more
360 @c recent case in fact works the other way.
361
362 @item x
363 @cindex extract from archive
364 @emph{Extract} members (named @var{member}) from the archive. You can
365 use the @samp{v} modifier with this operation, to request that
366 @command{ar} list each name as it extracts it.
367
368 If you do not specify a @var{member}, all files in the archive
369 are extracted.
370
371 @end table
372
373 A number of modifiers (@var{mod}) may immediately follow the @var{p}
374 keyletter, to specify variations on an operation's behavior:
375
376 @table @samp
377 @item a
378 @cindex relative placement in archive
379 Add new files @emph{after} an existing member of the
380 archive. If you use the modifier @samp{a}, the name of an existing archive
381 member must be present as the @var{relpos} argument, before the
382 @var{archive} specification.
383
384 @item b
385 Add new files @emph{before} an existing member of the
386 archive. If you use the modifier @samp{b}, the name of an existing archive
387 member must be present as the @var{relpos} argument, before the
388 @var{archive} specification. (same as @samp{i}).
389
390 @item c
391 @cindex creating archives
392 @emph{Create} the archive. The specified @var{archive} is always
393 created if it did not exist, when you request an update. But a warning is
394 issued unless you specify in advance that you expect to create it, by
395 using this modifier.
396
397 @item f
398 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
399 names of any length. This will cause it to create archives which are
400 not compatible with the native @command{ar} program on some systems. If
401 this is a concern, the @samp{f} modifier may be used to truncate file
402 names when putting them in the archive.
403
404 @item i
405 Insert new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{i}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{b}).
409
410 @item l
411 This modifier is accepted but not used.
412 @c whaffor ar l modifier??? presumably compat; with
413 @c what???---doc@@cygnus.com, 25jan91
414
415 @item N
416 Uses the @var{count} parameter. This is used if there are multiple
417 entries in the archive with the same name. Extract or delete instance
418 @var{count} of the given name from the archive.
419
420 @item o
421 @cindex dates in archive
422 Preserve the @emph{original} dates of members when extracting them. If
423 you do not specify this modifier, files extracted from the archive
424 are stamped with the time of extraction.
425
426 @item P
427 Use the full path name when matching names in the archive. @sc{gnu}
428 @command{ar} can not create an archive with a full path name (such archives
429 are not POSIX complaint), but other archive creators can. This option
430 will cause @sc{gnu} @command{ar} to match file names using a complete path
431 name, which can be convenient when extracting a single file from an
432 archive created by another tool.
433
434 @item s
435 @cindex writing archive index
436 Write an object-file index into the archive, or update an existing one,
437 even if no other change is made to the archive. You may use this modifier
438 flag either with any operation, or alone. Running @samp{ar s} on an
439 archive is equivalent to running @samp{ranlib} on it.
440
441 @item S
442 @cindex not writing archive index
443 Do not generate an archive symbol table. This can speed up building a
444 large library in several steps. The resulting archive can not be used
445 with the linker. In order to build a symbol table, you must omit the
446 @samp{S} modifier on the last execution of @samp{ar}, or you must run
447 @samp{ranlib} on the archive.
448
449 @item u
450 @cindex updating an archive
451 Normally, @samp{ar r}@dots{} inserts all files
452 listed into the archive. If you would like to insert @emph{only} those
453 of the files you list that are newer than existing members of the same
454 names, use this modifier. The @samp{u} modifier is allowed only for the
455 operation @samp{r} (replace). In particular, the combination @samp{qu} is
456 not allowed, since checking the timestamps would lose any speed
457 advantage from the operation @samp{q}.
458
459 @item v
460 This modifier requests the @emph{verbose} version of an operation. Many
461 operations display additional information, such as filenames processed,
462 when the modifier @samp{v} is appended.
463
464 @item V
465 This modifier shows the version number of @command{ar}.
466 @end table
467
468 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
469 compatibility with AIX. The behaviour produced by this option is the
470 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
471 @samp{-X} options; in particular, it does not support @option{-X32}
472 which is the default for AIX @command{ar}.
473
474 @c man end
475
476 @ignore
477 @c man begin SEEALSO ar
478 nm(1), ranlib(1), and the Info entries for @file{binutils}.
479 @c man end
480 @end ignore
481
482 @node ar scripts
483 @section Controlling @command{ar} with a Script
484
485 @smallexample
486 ar -M [ <@var{script} ]
487 @end smallexample
488
489 @cindex MRI compatibility, @command{ar}
490 @cindex scripts, @command{ar}
491 If you use the single command-line option @samp{-M} with @command{ar}, you
492 can control its operation with a rudimentary command language. This
493 form of @command{ar} operates interactively if standard input is coming
494 directly from a terminal. During interactive use, @command{ar} prompts for
495 input (the prompt is @samp{AR >}), and continues executing even after
496 errors. If you redirect standard input to a script file, no prompts are
497 issued, and @command{ar} abandons execution (with a nonzero exit code)
498 on any error.
499
500 The @command{ar} command language is @emph{not} designed to be equivalent
501 to the command-line options; in fact, it provides somewhat less control
502 over archives. The only purpose of the command language is to ease the
503 transition to @sc{gnu} @command{ar} for developers who already have scripts
504 written for the MRI ``librarian'' program.
505
506 The syntax for the @command{ar} command language is straightforward:
507 @itemize @bullet
508 @item
509 commands are recognized in upper or lower case; for example, @code{LIST}
510 is the same as @code{list}. In the following descriptions, commands are
511 shown in upper case for clarity.
512
513 @item
514 a single command may appear on each line; it is the first word on the
515 line.
516
517 @item
518 empty lines are allowed, and have no effect.
519
520 @item
521 comments are allowed; text after either of the characters @samp{*}
522 or @samp{;} is ignored.
523
524 @item
525 Whenever you use a list of names as part of the argument to an @command{ar}
526 command, you can separate the individual names with either commas or
527 blanks. Commas are shown in the explanations below, for clarity.
528
529 @item
530 @samp{+} is used as a line continuation character; if @samp{+} appears
531 at the end of a line, the text on the following line is considered part
532 of the current command.
533 @end itemize
534
535 Here are the commands you can use in @command{ar} scripts, or when using
536 @command{ar} interactively. Three of them have special significance:
537
538 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
539 a temporary file required for most of the other commands.
540
541 @code{SAVE} commits the changes so far specified by the script. Prior
542 to @code{SAVE}, commands affect only the temporary copy of the current
543 archive.
544
545 @table @code
546 @item ADDLIB @var{archive}
547 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
548 Add all the contents of @var{archive} (or, if specified, each named
549 @var{module} from @var{archive}) to the current archive.
550
551 Requires prior use of @code{OPEN} or @code{CREATE}.
552
553 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
554 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
555 @c else like "ar q..."
556 Add each named @var{member} as a module in the current archive.
557
558 Requires prior use of @code{OPEN} or @code{CREATE}.
559
560 @item CLEAR
561 Discard the contents of the current archive, canceling the effect of
562 any operations since the last @code{SAVE}. May be executed (with no
563 effect) even if no current archive is specified.
564
565 @item CREATE @var{archive}
566 Creates an archive, and makes it the current archive (required for many
567 other commands). The new archive is created with a temporary name; it
568 is not actually saved as @var{archive} until you use @code{SAVE}.
569 You can overwrite existing archives; similarly, the contents of any
570 existing file named @var{archive} will not be destroyed until @code{SAVE}.
571
572 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
573 Delete each listed @var{module} from the current archive; equivalent to
574 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
575
576 Requires prior use of @code{OPEN} or @code{CREATE}.
577
578 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
579 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
580 List each named @var{module} present in @var{archive}. The separate
581 command @code{VERBOSE} specifies the form of the output: when verbose
582 output is off, output is like that of @samp{ar -t @var{archive}
583 @var{module}@dots{}}. When verbose output is on, the listing is like
584 @samp{ar -tv @var{archive} @var{module}@dots{}}.
585
586 Output normally goes to the standard output stream; however, if you
587 specify @var{outputfile} as a final argument, @command{ar} directs the
588 output to that file.
589
590 @item END
591 Exit from @command{ar}, with a @code{0} exit code to indicate successful
592 completion. This command does not save the output file; if you have
593 changed the current archive since the last @code{SAVE} command, those
594 changes are lost.
595
596 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
597 Extract each named @var{module} from the current archive, writing them
598 into the current directory as separate files. Equivalent to @samp{ar -x
599 @var{archive} @var{module}@dots{}}.
600
601 Requires prior use of @code{OPEN} or @code{CREATE}.
602
603 @ignore
604 @c FIXME Tokens but no commands???
605 @item FULLDIR
606
607 @item HELP
608 @end ignore
609
610 @item LIST
611 Display full contents of the current archive, in ``verbose'' style
612 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
613 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
614 enhancement, rather than present for MRI compatibility.)
615
616 Requires prior use of @code{OPEN} or @code{CREATE}.
617
618 @item OPEN @var{archive}
619 Opens an existing archive for use as the current archive (required for
620 many other commands). Any changes as the result of subsequent commands
621 will not actually affect @var{archive} until you next use @code{SAVE}.
622
623 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
624 In the current archive, replace each existing @var{module} (named in
625 the @code{REPLACE} arguments) from files in the current working directory.
626 To execute this command without errors, both the file, and the module in
627 the current archive, must exist.
628
629 Requires prior use of @code{OPEN} or @code{CREATE}.
630
631 @item VERBOSE
632 Toggle an internal flag governing the output from @code{DIRECTORY}.
633 When the flag is on, @code{DIRECTORY} output matches output from
634 @samp{ar -tv }@dots{}.
635
636 @item SAVE
637 Commit your changes to the current archive, and actually save it as a
638 file with the name specified in the last @code{CREATE} or @code{OPEN}
639 command.
640
641 Requires prior use of @code{OPEN} or @code{CREATE}.
642
643 @end table
644
645 @iftex
646 @node ld
647 @chapter ld
648 @cindex linker
649 @kindex ld
650 The @sc{gnu} linker @command{ld} is now described in a separate manual.
651 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
652 @end iftex
653
654 @node nm
655 @chapter nm
656 @cindex symbols
657 @kindex nm
658
659 @c man title nm list symbols from object files
660
661 @smallexample
662 @c man begin SYNOPSIS nm
663 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
664 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
665 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
666 [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}]
667 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
668 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
669 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
670 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
671 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
672 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
673 @c man end
674 @end smallexample
675
676 @c man begin DESCRIPTION nm
677 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
678 If no object files are listed as arguments, @command{nm} assumes the file
679 @file{a.out}.
680
681 For each symbol, @command{nm} shows:
682
683 @itemize @bullet
684 @item
685 The symbol value, in the radix selected by options (see below), or
686 hexadecimal by default.
687
688 @item
689 The symbol type. At least the following types are used; others are, as
690 well, depending on the object file format. If lowercase, the symbol is
691 local; if uppercase, the symbol is global (external).
692
693 @c Some more detail on exactly what these symbol types are used for
694 @c would be nice.
695 @table @code
696 @item A
697 The symbol's value is absolute, and will not be changed by further
698 linking.
699
700 @item B
701 The symbol is in the uninitialized data section (known as BSS).
702
703 @item C
704 The symbol is common. Common symbols are uninitialized data. When
705 linking, multiple common symbols may appear with the same name. If the
706 symbol is defined anywhere, the common symbols are treated as undefined
707 references.
708 @ifclear man
709 For more details on common symbols, see the discussion of
710 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
711 @end ifclear
712
713 @item D
714 The symbol is in the initialized data section.
715
716 @item G
717 The symbol is in an initialized data section for small objects. Some
718 object file formats permit more efficient access to small data objects,
719 such as a global int variable as opposed to a large global array.
720
721 @item I
722 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
723 extension to the a.out object file format which is rarely used.
724
725 @item N
726 The symbol is a debugging symbol.
727
728 @item R
729 The symbol is in a read only data section.
730
731 @item S
732 The symbol is in an uninitialized data section for small objects.
733
734 @item T
735 The symbol is in the text (code) section.
736
737 @item U
738 The symbol is undefined.
739
740 @item V
741 The symbol is a weak object. When a weak defined symbol is linked with
742 a normal defined symbol, the normal defined symbol is used with no error.
743 When a weak undefined symbol is linked and the symbol is not defined,
744 the value of the weak symbol becomes zero with no error.
745
746 @item W
747 The symbol is a weak symbol that has not been specifically tagged as a
748 weak object symbol. When a weak defined symbol is linked with a normal
749 defined symbol, the normal defined symbol is used with no error.
750 When a weak undefined symbol is linked and the symbol is not defined,
751 the value of the symbol is determined in a system-specific manner without
752 error. On some systems, uppercase indicates that a default value has been
753 specified.
754
755
756 @item -
757 The symbol is a stabs symbol in an a.out object file. In this case, the
758 next values printed are the stabs other field, the stabs desc field, and
759 the stab type. Stabs symbols are used to hold debugging information.
760 @ifclear man
761 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
762 ``stabs'' debug format}.
763 @end ifclear
764
765 @item ?
766 The symbol type is unknown, or object file format specific.
767 @end table
768
769 @item
770 The symbol name.
771 @end itemize
772
773 @c man end
774
775 @c man begin OPTIONS nm
776 The long and short forms of options, shown here as alternatives, are
777 equivalent.
778
779 @table @env
780 @item -A
781 @itemx -o
782 @itemx --print-file-name
783 @cindex input file name
784 @cindex file name
785 @cindex source file name
786 Precede each symbol by the name of the input file (or archive member)
787 in which it was found, rather than identifying the input file once only,
788 before all of its symbols.
789
790 @item -a
791 @itemx --debug-syms
792 @cindex debugging symbols
793 Display all symbols, even debugger-only symbols; normally these are not
794 listed.
795
796 @item -B
797 @cindex @command{nm} format
798 @cindex @command{nm} compatibility
799 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
800
801 @item -C
802 @itemx --demangle[=@var{style}]
803 @cindex demangling in nm
804 Decode (@dfn{demangle}) low-level symbol names into user-level names.
805 Besides removing any initial underscore prepended by the system, this
806 makes C++ function names readable. Different compilers have different
807 mangling styles. The optional demangling style argument can be used to
808 choose an appropriate demangling style for your compiler. @xref{c++filt},
809 for more information on demangling.
810
811 @item --no-demangle
812 Do not demangle low-level symbol names. This is the default.
813
814 @item -D
815 @itemx --dynamic
816 @cindex dynamic symbols
817 Display the dynamic symbols rather than the normal symbols. This is
818 only meaningful for dynamic objects, such as certain types of shared
819 libraries.
820
821 @item -f @var{format}
822 @itemx --format=@var{format}
823 @cindex @command{nm} format
824 @cindex @command{nm} compatibility
825 Use the output format @var{format}, which can be @code{bsd},
826 @code{sysv}, or @code{posix}. The default is @code{bsd}.
827 Only the first character of @var{format} is significant; it can be
828 either upper or lower case.
829
830 @item -g
831 @itemx --extern-only
832 @cindex external symbols
833 Display only external symbols.
834
835 @item -l
836 @itemx --line-numbers
837 @cindex symbol line numbers
838 For each symbol, use debugging information to try to find a filename and
839 line number. For a defined symbol, look for the line number of the
840 address of the symbol. For an undefined symbol, look for the line
841 number of a relocation entry which refers to the symbol. If line number
842 information can be found, print it after the other symbol information.
843
844 @item -n
845 @itemx -v
846 @itemx --numeric-sort
847 Sort symbols numerically by their addresses, rather than alphabetically
848 by their names.
849
850 @item -p
851 @itemx --no-sort
852 @cindex sorting symbols
853 Do not bother to sort the symbols in any order; print them in the order
854 encountered.
855
856 @item -P
857 @itemx --portability
858 Use the POSIX.2 standard output format instead of the default format.
859 Equivalent to @samp{-f posix}.
860
861 @item -S
862 @itemx --print-size
863 Print size, not the value, of defined symbols for the @code{bsd} output format.
864
865 @item -s
866 @itemx --print-armap
867 @cindex symbol index, listing
868 When listing symbols from archive members, include the index: a mapping
869 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
870 contain definitions for which names.
871
872 @item -r
873 @itemx --reverse-sort
874 Reverse the order of the sort (whether numeric or alphabetic); let the
875 last come first.
876
877 @item --size-sort
878 Sort symbols by size. The size is computed as the difference between
879 the value of the symbol and the value of the symbol with the next higher
880 value. If the @code{bsd} output format is used the size of the symbol
881 is printed, rather than the value, and @samp{-S} must be used in order
882 both size and value to be printed.
883
884 @item --special-syms
885 Display symbols which have a target-specific special meaning. These
886 symbols are usually used by the target for some special processing and
887 are not normally helpful when included included in the normal symbol
888 lists. For example for ARM targets this option would skip the mapping
889 symbols used to mark transistions between ARM code, THUMB code and
890 data.
891
892 @item -t @var{radix}
893 @itemx --radix=@var{radix}
894 Use @var{radix} as the radix for printing the symbol values. It must be
895 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
896
897 @item --target=@var{bfdname}
898 @cindex object code format
899 Specify an object code format other than your system's default format.
900 @xref{Target Selection}, for more information.
901
902 @item -u
903 @itemx --undefined-only
904 @cindex external symbols
905 @cindex undefined symbols
906 Display only undefined symbols (those external to each object file).
907
908 @item --defined-only
909 @cindex external symbols
910 @cindex undefined symbols
911 Display only defined symbols for each object file.
912
913 @item -V
914 @itemx --version
915 Show the version number of @command{nm} and exit.
916
917 @item -X
918 This option is ignored for compatibility with the AIX version of
919 @command{nm}. It takes one parameter which must be the string
920 @option{32_64}. The default mode of AIX @command{nm} corresponds
921 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
922
923 @item --help
924 Show a summary of the options to @command{nm} and exit.
925 @end table
926
927 @c man end
928
929 @ignore
930 @c man begin SEEALSO nm
931 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
932 @c man end
933 @end ignore
934
935 @node objcopy
936 @chapter objcopy
937
938 @c man title objcopy copy and translate object files
939
940 @smallexample
941 @c man begin SYNOPSIS objcopy
942 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
943 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
944 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
945 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
946 [@option{-S}|@option{--strip-all}]
947 [@option{-g}|@option{--strip-debug}]
948 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
949 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
950 [@option{--strip-unneeded-symbol=}@var{symbolname}]
951 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
952 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
953 [@option{--globalize-symbol=}@var{symbolname}]
954 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
955 [@option{-w}|@option{--wildcard}]
956 [@option{-x}|@option{--discard-all}]
957 [@option{-X}|@option{--discard-locals}]
958 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
959 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
960 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
961 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
962 [@option{-p}|@option{--preserve-dates}]
963 [@option{--debugging}]
964 [@option{--gap-fill=}@var{val}]
965 [@option{--pad-to=}@var{address}]
966 [@option{--set-start=}@var{val}]
967 [@option{--adjust-start=}@var{incr}]
968 [@option{--change-addresses=}@var{incr}]
969 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
970 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
971 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
972 [@option{--change-warnings}] [@option{--no-change-warnings}]
973 [@option{--set-section-flags} @var{section}=@var{flags}]
974 [@option{--add-section} @var{sectionname}=@var{filename}]
975 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
976 [@option{--change-leading-char}] [@option{--remove-leading-char}]
977 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
978 [@option{--redefine-sym} @var{old}=@var{new}]
979 [@option{--redefine-syms=}@var{filename}]
980 [@option{--weaken}]
981 [@option{--keep-symbols=}@var{filename}]
982 [@option{--strip-symbols=}@var{filename}]
983 [@option{--strip-unneeded-symbols=}@var{filename}]
984 [@option{--keep-global-symbols=}@var{filename}]
985 [@option{--localize-symbols=}@var{filename}]
986 [@option{--globalize-symbols=}@var{filename}]
987 [@option{--weaken-symbols=}@var{filename}]
988 [@option{--alt-machine-code=}@var{index}]
989 [@option{--prefix-symbols=}@var{string}]
990 [@option{--prefix-sections=}@var{string}]
991 [@option{--prefix-alloc-sections=}@var{string}]
992 [@option{--add-gnu-debuglink=}@var{path-to-file}]
993 [@option{--only-keep-debug}]
994 [@option{--writable-text}]
995 [@option{--readonly-text}]
996 [@option{--pure}]
997 [@option{--impure}]
998 [@option{-v}|@option{--verbose}]
999 [@option{-V}|@option{--version}]
1000 [@option{--help}] [@option{--info}]
1001 @var{infile} [@var{outfile}]
1002 @c man end
1003 @end smallexample
1004
1005 @c man begin DESCRIPTION objcopy
1006 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1007 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1008 read and write the object files. It can write the destination object
1009 file in a format different from that of the source object file. The
1010 exact behavior of @command{objcopy} is controlled by command-line options.
1011 Note that @command{objcopy} should be able to copy a fully linked file
1012 between any two formats. However, copying a relocatable object file
1013 between any two formats may not work as expected.
1014
1015 @command{objcopy} creates temporary files to do its translations and
1016 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1017 translation work; it has access to all the formats described in @sc{bfd}
1018 and thus is able to recognize most formats without being told
1019 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1020
1021 @command{objcopy} can be used to generate S-records by using an output
1022 target of @samp{srec} (e.g., use @samp{-O srec}).
1023
1024 @command{objcopy} can be used to generate a raw binary file by using an
1025 output target of @samp{binary} (e.g., use @option{-O binary}). When
1026 @command{objcopy} generates a raw binary file, it will essentially produce
1027 a memory dump of the contents of the input object file. All symbols and
1028 relocation information will be discarded. The memory dump will start at
1029 the load address of the lowest section copied into the output file.
1030
1031 When generating an S-record or a raw binary file, it may be helpful to
1032 use @option{-S} to remove sections containing debugging information. In
1033 some cases @option{-R} will be useful to remove sections which contain
1034 information that is not needed by the binary file.
1035
1036 Note---@command{objcopy} is not able to change the endianness of its input
1037 files. If the input format has an endianness (some formats do not),
1038 @command{objcopy} can only copy the inputs into file formats that have the
1039 same endianness or which have no endianness (e.g., @samp{srec}).
1040
1041 @c man end
1042
1043 @c man begin OPTIONS objcopy
1044
1045 @table @env
1046 @item @var{infile}
1047 @itemx @var{outfile}
1048 The input and output files, respectively.
1049 If you do not specify @var{outfile}, @command{objcopy} creates a
1050 temporary file and destructively renames the result with
1051 the name of @var{infile}.
1052
1053 @item -I @var{bfdname}
1054 @itemx --input-target=@var{bfdname}
1055 Consider the source file's object format to be @var{bfdname}, rather than
1056 attempting to deduce it. @xref{Target Selection}, for more information.
1057
1058 @item -O @var{bfdname}
1059 @itemx --output-target=@var{bfdname}
1060 Write the output file using the object format @var{bfdname}.
1061 @xref{Target Selection}, for more information.
1062
1063 @item -F @var{bfdname}
1064 @itemx --target=@var{bfdname}
1065 Use @var{bfdname} as the object format for both the input and the output
1066 file; i.e., simply transfer data from source to destination with no
1067 translation. @xref{Target Selection}, for more information.
1068
1069 @item -B @var{bfdarch}
1070 @itemx --binary-architecture=@var{bfdarch}
1071 Useful when transforming a raw binary input file into an object file.
1072 In this case the output architecture can be set to @var{bfdarch}. This
1073 option will be ignored if the input file has a known @var{bfdarch}. You
1074 can access this binary data inside a program by referencing the special
1075 symbols that are created by the conversion process. These symbols are
1076 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1077 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1078 an object file and then access it in your code using these symbols.
1079
1080 @item -j @var{sectionname}
1081 @itemx --only-section=@var{sectionname}
1082 Copy only the named section from the input file to the output file.
1083 This option may be given more than once. Note that using this option
1084 inappropriately may make the output file unusable.
1085
1086 @item -R @var{sectionname}
1087 @itemx --remove-section=@var{sectionname}
1088 Remove any section named @var{sectionname} from the output file. This
1089 option may be given more than once. Note that using this option
1090 inappropriately may make the output file unusable.
1091
1092 @item -S
1093 @itemx --strip-all
1094 Do not copy relocation and symbol information from the source file.
1095
1096 @item -g
1097 @itemx --strip-debug
1098 Do not copy debugging symbols or sections from the source file.
1099
1100 @item --strip-unneeded
1101 Strip all symbols that are not needed for relocation processing.
1102
1103 @item -K @var{symbolname}
1104 @itemx --keep-symbol=@var{symbolname}
1105 Copy only symbol @var{symbolname} from the source file. This option may
1106 be given more than once.
1107
1108 @item -N @var{symbolname}
1109 @itemx --strip-symbol=@var{symbolname}
1110 Do not copy symbol @var{symbolname} from the source file. This option
1111 may be given more than once.
1112
1113 @item --strip-unneeded-symbol=@var{symbolname}
1114 Do not copy symbol @var{symbolname} from the source file unless it is needed
1115 by a relocation. This option may be given more than once.
1116
1117 @item -G @var{symbolname}
1118 @itemx --keep-global-symbol=@var{symbolname}
1119 Keep only symbol @var{symbolname} global. Make all other symbols local
1120 to the file, so that they are not visible externally. This option may
1121 be given more than once.
1122
1123 @item -L @var{symbolname}
1124 @itemx --localize-symbol=@var{symbolname}
1125 Make symbol @var{symbolname} local to the file, so that it is not
1126 visible externally. This option may be given more than once.
1127
1128 @item -W @var{symbolname}
1129 @itemx --weaken-symbol=@var{symbolname}
1130 Make symbol @var{symbolname} weak. This option may be given more than once.
1131
1132 @item --globalize-symbol=@var{symbolname}
1133 Give symbol @var{symbolname} global scoping so that it is visible
1134 outside of the file in which it is defined. This option may be given
1135 more than once.
1136
1137 @item -w
1138 @itemx --wildcard
1139 Permit regular expressions in @var{symbolname}s used in other command
1140 line options. The question mark (?), asterisk (*), backslash (\) and
1141 square brackets ([]) operators can be used anywhere in the symbol
1142 name. If the first character of the symbol name is the exclamation
1143 point (!) then the sense of the switch is reversed for that symbol.
1144 For example:
1145
1146 @smallexample
1147 -w -W !foo -W fo*
1148 @end smallexample
1149
1150 would cause objcopy to weaken all symbols that start with ``fo''
1151 except for the symbol ``foo''.
1152
1153 @item -x
1154 @itemx --discard-all
1155 Do not copy non-global symbols from the source file.
1156 @c FIXME any reason to prefer "non-global" to "local" here?
1157
1158 @item -X
1159 @itemx --discard-locals
1160 Do not copy compiler-generated local symbols.
1161 (These usually start with @samp{L} or @samp{.}.)
1162
1163 @item -b @var{byte}
1164 @itemx --byte=@var{byte}
1165 Keep only every @var{byte}th byte of the input file (header data is not
1166 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1167 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1168 option, or the default of 4. This option is useful for creating files
1169 to program @sc{rom}. It is typically used with an @code{srec} output
1170 target.
1171
1172 @item -i @var{interleave}
1173 @itemx --interleave=@var{interleave}
1174 Only copy one out of every @var{interleave} bytes. Select which byte to
1175 copy with the @option{-b} or @option{--byte} option. The default is 4.
1176 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1177 @option{--byte}.
1178
1179 @item -p
1180 @itemx --preserve-dates
1181 Set the access and modification dates of the output file to be the same
1182 as those of the input file.
1183
1184 @item --debugging
1185 Convert debugging information, if possible. This is not the default
1186 because only certain debugging formats are supported, and the
1187 conversion process can be time consuming.
1188
1189 @item --gap-fill @var{val}
1190 Fill gaps between sections with @var{val}. This operation applies to
1191 the @emph{load address} (LMA) of the sections. It is done by increasing
1192 the size of the section with the lower address, and filling in the extra
1193 space created with @var{val}.
1194
1195 @item --pad-to @var{address}
1196 Pad the output file up to the load address @var{address}. This is
1197 done by increasing the size of the last section. The extra space is
1198 filled in with the value specified by @option{--gap-fill} (default zero).
1199
1200 @item --set-start @var{val}
1201 Set the start address of the new file to @var{val}. Not all object file
1202 formats support setting the start address.
1203
1204 @item --change-start @var{incr}
1205 @itemx --adjust-start @var{incr}
1206 @cindex changing start address
1207 Change the start address by adding @var{incr}. Not all object file
1208 formats support setting the start address.
1209
1210 @item --change-addresses @var{incr}
1211 @itemx --adjust-vma @var{incr}
1212 @cindex changing object addresses
1213 Change the VMA and LMA addresses of all sections, as well as the start
1214 address, by adding @var{incr}. Some object file formats do not permit
1215 section addresses to be changed arbitrarily. Note that this does not
1216 relocate the sections; if the program expects sections to be loaded at a
1217 certain address, and this option is used to change the sections such
1218 that they are loaded at a different address, the program may fail.
1219
1220 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1221 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1222 @cindex changing section address
1223 Set or change both the VMA address and the LMA address of the named
1224 @var{section}. If @samp{=} is used, the section address is set to
1225 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1226 section address. See the comments under @option{--change-addresses},
1227 above. If @var{section} does not exist in the input file, a warning will
1228 be issued, unless @option{--no-change-warnings} is used.
1229
1230 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1231 @cindex changing section LMA
1232 Set or change the LMA address of the named @var{section}. The LMA
1233 address is the address where the section will be loaded into memory at
1234 program load time. Normally this is the same as the VMA address, which
1235 is the address of the section at program run time, but on some systems,
1236 especially those where a program is held in ROM, the two can be
1237 different. If @samp{=} is used, the section address is set to
1238 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1239 section address. See the comments under @option{--change-addresses},
1240 above. If @var{section} does not exist in the input file, a warning
1241 will be issued, unless @option{--no-change-warnings} is used.
1242
1243 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1244 @cindex changing section VMA
1245 Set or change the VMA address of the named @var{section}. The VMA
1246 address is the address where the section will be located once the
1247 program has started executing. Normally this is the same as the LMA
1248 address, which is the address where the section will be loaded into
1249 memory, but on some systems, especially those where a program is held in
1250 ROM, the two can be different. If @samp{=} is used, the section address
1251 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1252 from the section address. See the comments under
1253 @option{--change-addresses}, above. If @var{section} does not exist in
1254 the input file, a warning will be issued, unless
1255 @option{--no-change-warnings} is used.
1256
1257 @item --change-warnings
1258 @itemx --adjust-warnings
1259 If @option{--change-section-address} or @option{--change-section-lma} or
1260 @option{--change-section-vma} is used, and the named section does not
1261 exist, issue a warning. This is the default.
1262
1263 @item --no-change-warnings
1264 @itemx --no-adjust-warnings
1265 Do not issue a warning if @option{--change-section-address} or
1266 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1267 if the named section does not exist.
1268
1269 @item --set-section-flags @var{section}=@var{flags}
1270 Set the flags for the named section. The @var{flags} argument is a
1271 comma separated string of flag names. The recognized names are
1272 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1273 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1274 @samp{debug}. You can set the @samp{contents} flag for a section which
1275 does not have contents, but it is not meaningful to clear the
1276 @samp{contents} flag of a section which does have contents--just remove
1277 the section instead. Not all flags are meaningful for all object file
1278 formats.
1279
1280 @item --add-section @var{sectionname}=@var{filename}
1281 Add a new section named @var{sectionname} while copying the file. The
1282 contents of the new section are taken from the file @var{filename}. The
1283 size of the section will be the size of the file. This option only
1284 works on file formats which can support sections with arbitrary names.
1285
1286 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1287 Rename a section from @var{oldname} to @var{newname}, optionally
1288 changing the section's flags to @var{flags} in the process. This has
1289 the advantage over usng a linker script to perform the rename in that
1290 the output stays as an object file and does not become a linked
1291 executable.
1292
1293 This option is particularly helpful when the input format is binary,
1294 since this will always create a section called .data. If for example,
1295 you wanted instead to create a section called .rodata containing binary
1296 data you could use the following command line to achieve it:
1297
1298 @smallexample
1299 objcopy -I binary -O <output_format> -B <architecture> \
1300 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1301 <input_binary_file> <output_object_file>
1302 @end smallexample
1303
1304 @item --change-leading-char
1305 Some object file formats use special characters at the start of
1306 symbols. The most common such character is underscore, which compilers
1307 often add before every symbol. This option tells @command{objcopy} to
1308 change the leading character of every symbol when it converts between
1309 object file formats. If the object file formats use the same leading
1310 character, this option has no effect. Otherwise, it will add a
1311 character, or remove a character, or change a character, as
1312 appropriate.
1313
1314 @item --remove-leading-char
1315 If the first character of a global symbol is a special symbol leading
1316 character used by the object file format, remove the character. The
1317 most common symbol leading character is underscore. This option will
1318 remove a leading underscore from all global symbols. This can be useful
1319 if you want to link together objects of different file formats with
1320 different conventions for symbol names. This is different from
1321 @option{--change-leading-char} because it always changes the symbol name
1322 when appropriate, regardless of the object file format of the output
1323 file.
1324
1325 @item --srec-len=@var{ival}
1326 Meaningful only for srec output. Set the maximum length of the Srecords
1327 being produced to @var{ival}. This length covers both address, data and
1328 crc fields.
1329
1330 @item --srec-forceS3
1331 Meaningful only for srec output. Avoid generation of S1/S2 records,
1332 creating S3-only record format.
1333
1334 @item --redefine-sym @var{old}=@var{new}
1335 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1336 when one is trying link two things together for which you have no
1337 source, and there are name collisions.
1338
1339 @item --redefine-syms=@var{filename}
1340 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1341 listed in the file @var{filename}. @var{filename} is simply a flat file,
1342 with one symbol pair per line. Line comments may be introduced by the hash
1343 character. This option may be given more than once.
1344
1345 @item --weaken
1346 Change all global symbols in the file to be weak. This can be useful
1347 when building an object which will be linked against other objects using
1348 the @option{-R} option to the linker. This option is only effective when
1349 using an object file format which supports weak symbols.
1350
1351 @item --keep-symbols=@var{filename}
1352 Apply @option{--keep-symbol} option to each symbol listed in the file
1353 @var{filename}. @var{filename} is simply a flat file, with one symbol
1354 name per line. Line comments may be introduced by the hash character.
1355 This option may be given more than once.
1356
1357 @item --strip-symbols=@var{filename}
1358 Apply @option{--strip-symbol} option to each symbol listed in the file
1359 @var{filename}. @var{filename} is simply a flat file, with one symbol
1360 name per line. Line comments may be introduced by the hash character.
1361 This option may be given more than once.
1362
1363 @item --strip-unneeded-symbols=@var{filename}
1364 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1365 the file @var{filename}. @var{filename} is simply a flat file, with one
1366 symbol name per line. Line comments may be introduced by the hash
1367 character. This option may be given more than once.
1368
1369 @item --keep-global-symbols=@var{filename}
1370 Apply @option{--keep-global-symbol} option to each symbol listed in the
1371 file @var{filename}. @var{filename} is simply a flat file, with one
1372 symbol name per line. Line comments may be introduced by the hash
1373 character. This option may be given more than once.
1374
1375 @item --localize-symbols=@var{filename}
1376 Apply @option{--localize-symbol} option to each symbol listed in the file
1377 @var{filename}. @var{filename} is simply a flat file, with one symbol
1378 name per line. Line comments may be introduced by the hash character.
1379 This option may be given more than once.
1380
1381 @item --globalize-symbols=@var{filename}
1382 Apply @option{--globalize-symbol} option to each symbol listed in the file
1383 @var{filename}. @var{filename} is simply a flat file, with one symbol
1384 name per line. Line comments may be introduced by the hash character.
1385 This option may be given more than once.
1386
1387 @item --weaken-symbols=@var{filename}
1388 Apply @option{--weaken-symbol} option to each symbol listed in the file
1389 @var{filename}. @var{filename} is simply a flat file, with one symbol
1390 name per line. Line comments may be introduced by the hash character.
1391 This option may be given more than once.
1392
1393 @item --alt-machine-code=@var{index}
1394 If the output architecture has alternate machine codes, use the
1395 @var{index}th code instead of the default one. This is useful in case
1396 a machine is assigned an official code and the tool-chain adopts the
1397 new code, but other applications still depend on the original code
1398 being used.
1399
1400 @item --writable-text
1401 Mark the output text as writable. This option isn't meaningful for all
1402 object file formats.
1403
1404 @item --readonly-text
1405 Make the output text write protected. This option isn't meaningful for all
1406 object file formats.
1407
1408 @item --pure
1409 Mark the output file as demand paged. This option isn't meaningful for all
1410 object file formats.
1411
1412 @item --impure
1413 Mark the output file as impure. This option isn't meaningful for all
1414 object file formats.
1415
1416 @item --prefix-symbols=@var{string}
1417 Prefix all symbols in the output file with @var{string}.
1418
1419 @item --prefix-sections=@var{string}
1420 Prefix all section names in the output file with @var{string}.
1421
1422 @item --prefix-alloc-sections=@var{string}
1423 Prefix all the names of all allocated sections in the output file with
1424 @var{string}.
1425
1426 @item --add-gnu-debuglink=@var{path-to-file}
1427 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1428 and adds it to the output file.
1429
1430 @item --only-keep-debug
1431 Strip a file, removing any sections that would be stripped by
1432 @option{--strip-debug} and leaving the debugging sections.
1433
1434 The intention is that this option will be used in conjunction with
1435 @option{--add-gnu-debuglink} to create a two part executable. One a
1436 stripped binary which will occupy less space in RAM and in a
1437 distribution and the second a debugging information file which is only
1438 needed if debugging abilities are required. The suggested procedure
1439 to create these files is as follows:
1440
1441 @enumerate
1442 @item Link the executable as normal. Assuming that is is called
1443 @code{foo} then...
1444 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1445 create a file containing the debugging info.
1446 @item Run @code{objcopy --strip-debug foo} to create a
1447 stripped executable.
1448 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1449 to add a link to the debugging info into the stripped executable.
1450 @end enumerate
1451
1452 Note - the choice of @code{.dbg} as an extension for the debug info
1453 file is arbitrary. Also the @code{--only-keep-debug} step is
1454 optional. You could instead do this:
1455
1456 @enumerate
1457 @item Link the executable as normal.
1458 @item Copy @code{foo} to @code{foo.full}
1459 @item Run @code{objcopy --strip-debug foo}
1460 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1461 @end enumerate
1462
1463 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
1464 full executable. It does not have to be a file created by the
1465 @option{--only-keep-debug} switch.
1466
1467 @item -V
1468 @itemx --version
1469 Show the version number of @command{objcopy}.
1470
1471 @item -v
1472 @itemx --verbose
1473 Verbose output: list all object files modified. In the case of
1474 archives, @samp{objcopy -V} lists all members of the archive.
1475
1476 @item --help
1477 Show a summary of the options to @command{objcopy}.
1478
1479 @item --info
1480 Display a list showing all architectures and object formats available.
1481 @end table
1482
1483 @c man end
1484
1485 @ignore
1486 @c man begin SEEALSO objcopy
1487 ld(1), objdump(1), and the Info entries for @file{binutils}.
1488 @c man end
1489 @end ignore
1490
1491 @node objdump
1492 @chapter objdump
1493
1494 @cindex object file information
1495 @kindex objdump
1496
1497 @c man title objdump display information from object files.
1498
1499 @smallexample
1500 @c man begin SYNOPSIS objdump
1501 objdump [@option{-a}|@option{--archive-headers}]
1502 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1503 [@option{-C}|@option{--demangle}[=@var{style}] ]
1504 [@option{-d}|@option{--disassemble}]
1505 [@option{-D}|@option{--disassemble-all}]
1506 [@option{-z}|@option{--disassemble-zeroes}]
1507 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1508 [@option{-f}|@option{--file-headers}]
1509 [@option{--file-start-context}]
1510 [@option{-g}|@option{--debugging}]
1511 [@option{-e}|@option{--debugging-tags}]
1512 [@option{-h}|@option{--section-headers}|@option{--headers}]
1513 [@option{-i}|@option{--info}]
1514 [@option{-j} @var{section}|@option{--section=}@var{section}]
1515 [@option{-l}|@option{--line-numbers}]
1516 [@option{-S}|@option{--source}]
1517 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1518 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1519 [@option{-p}|@option{--private-headers}]
1520 [@option{-r}|@option{--reloc}]
1521 [@option{-R}|@option{--dynamic-reloc}]
1522 [@option{-s}|@option{--full-contents}]
1523 [@option{-G}|@option{--stabs}]
1524 [@option{-t}|@option{--syms}]
1525 [@option{-T}|@option{--dynamic-syms}]
1526 [@option{-x}|@option{--all-headers}]
1527 [@option{-w}|@option{--wide}]
1528 [@option{--start-address=}@var{address}]
1529 [@option{--stop-address=}@var{address}]
1530 [@option{--prefix-addresses}]
1531 [@option{--[no-]show-raw-insn}]
1532 [@option{--adjust-vma=}@var{offset}]
1533 [@option{--special-syms}]
1534 [@option{-V}|@option{--version}]
1535 [@option{-H}|@option{--help}]
1536 @var{objfile}@dots{}
1537 @c man end
1538 @end smallexample
1539
1540 @c man begin DESCRIPTION objdump
1541
1542 @command{objdump} displays information about one or more object files.
1543 The options control what particular information to display. This
1544 information is mostly useful to programmers who are working on the
1545 compilation tools, as opposed to programmers who just want their
1546 program to compile and work.
1547
1548 @var{objfile}@dots{} are the object files to be examined. When you
1549 specify archives, @command{objdump} shows information on each of the member
1550 object files.
1551
1552 @c man end
1553
1554 @c man begin OPTIONS objdump
1555
1556 The long and short forms of options, shown here as alternatives, are
1557 equivalent. At least one option from the list
1558 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1559
1560 @table @env
1561 @item -a
1562 @itemx --archive-header
1563 @cindex archive headers
1564 If any of the @var{objfile} files are archives, display the archive
1565 header information (in a format similar to @samp{ls -l}). Besides the
1566 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1567 the object file format of each archive member.
1568
1569 @item --adjust-vma=@var{offset}
1570 @cindex section addresses in objdump
1571 @cindex VMA in objdump
1572 When dumping information, first add @var{offset} to all the section
1573 addresses. This is useful if the section addresses do not correspond to
1574 the symbol table, which can happen when putting sections at particular
1575 addresses when using a format which can not represent section addresses,
1576 such as a.out.
1577
1578 @item -b @var{bfdname}
1579 @itemx --target=@var{bfdname}
1580 @cindex object code format
1581 Specify that the object-code format for the object files is
1582 @var{bfdname}. This option may not be necessary; @var{objdump} can
1583 automatically recognize many formats.
1584
1585 For example,
1586 @example
1587 objdump -b oasys -m vax -h fu.o
1588 @end example
1589 @noindent
1590 displays summary information from the section headers (@option{-h}) of
1591 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1592 file in the format produced by Oasys compilers. You can list the
1593 formats available with the @option{-i} option.
1594 @xref{Target Selection}, for more information.
1595
1596 @item -C
1597 @itemx --demangle[=@var{style}]
1598 @cindex demangling in objdump
1599 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1600 Besides removing any initial underscore prepended by the system, this
1601 makes C++ function names readable. Different compilers have different
1602 mangling styles. The optional demangling style argument can be used to
1603 choose an appropriate demangling style for your compiler. @xref{c++filt},
1604 for more information on demangling.
1605
1606 @item -g
1607 @itemx --debugging
1608 Display debugging information. This attempts to parse debugging
1609 information stored in the file and print it out using a C like syntax.
1610 Only certain types of debugging information have been implemented.
1611 Some other types are supported by @command{readelf -w}.
1612 @xref{readelf}.
1613
1614 @item -e
1615 @itemx --debugging-tags
1616 Like @option{-g}, but the information is generated in a format compatible
1617 with ctags tool.
1618
1619 @item -d
1620 @itemx --disassemble
1621 @cindex disassembling object code
1622 @cindex machine instructions
1623 Display the assembler mnemonics for the machine instructions from
1624 @var{objfile}. This option only disassembles those sections which are
1625 expected to contain instructions.
1626
1627 @item -D
1628 @itemx --disassemble-all
1629 Like @option{-d}, but disassemble the contents of all sections, not just
1630 those expected to contain instructions.
1631
1632 @item --prefix-addresses
1633 When disassembling, print the complete address on each line. This is
1634 the older disassembly format.
1635
1636 @item -EB
1637 @itemx -EL
1638 @itemx --endian=@{big|little@}
1639 @cindex endianness
1640 @cindex disassembly endianness
1641 Specify the endianness of the object files. This only affects
1642 disassembly. This can be useful when disassembling a file format which
1643 does not describe endianness information, such as S-records.
1644
1645 @item -f
1646 @itemx --file-headers
1647 @cindex object file header
1648 Display summary information from the overall header of
1649 each of the @var{objfile} files.
1650
1651 @item --file-start-context
1652 @cindex source code context
1653 Specify that when displaying interlisted source code/disassembly
1654 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1655 context to the start of the file.
1656
1657 @item -h
1658 @itemx --section-headers
1659 @itemx --headers
1660 @cindex section headers
1661 Display summary information from the section headers of the
1662 object file.
1663
1664 File segments may be relocated to nonstandard addresses, for example by
1665 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1666 @command{ld}. However, some object file formats, such as a.out, do not
1667 store the starting address of the file segments. In those situations,
1668 although @command{ld} relocates the sections correctly, using @samp{objdump
1669 -h} to list the file section headers cannot show the correct addresses.
1670 Instead, it shows the usual addresses, which are implicit for the
1671 target.
1672
1673 @item -H
1674 @itemx --help
1675 Print a summary of the options to @command{objdump} and exit.
1676
1677 @item -i
1678 @itemx --info
1679 @cindex architectures available
1680 @cindex object formats available
1681 Display a list showing all architectures and object formats available
1682 for specification with @option{-b} or @option{-m}.
1683
1684 @item -j @var{name}
1685 @itemx --section=@var{name}
1686 @cindex section information
1687 Display information only for section @var{name}.
1688
1689 @item -l
1690 @itemx --line-numbers
1691 @cindex source filenames for object files
1692 Label the display (using debugging information) with the filename and
1693 source line numbers corresponding to the object code or relocs shown.
1694 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1695
1696 @item -m @var{machine}
1697 @itemx --architecture=@var{machine}
1698 @cindex architecture
1699 @cindex disassembly architecture
1700 Specify the architecture to use when disassembling object files. This
1701 can be useful when disassembling object files which do not describe
1702 architecture information, such as S-records. You can list the available
1703 architectures with the @option{-i} option.
1704
1705 @item -M @var{options}
1706 @itemx --disassembler-options=@var{options}
1707 Pass target specific information to the disassembler. Only supported on
1708 some targets. If it is necessary to specify more than one
1709 disassembler option then multiple @option{-M} options can be used or
1710 can be placed together into a comma separated list.
1711
1712 If the target is an ARM architecture then this switch can be used to
1713 select which register name set is used during disassembler. Specifying
1714 @option{-M reg-name-std} (the default) will select the register names as
1715 used in ARM's instruction set documentation, but with register 13 called
1716 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1717 @option{-M reg-names-apcs} will select the name set used by the ARM
1718 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1719 just use @samp{r} followed by the register number.
1720
1721 There are also two variants on the APCS register naming scheme enabled
1722 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1723 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1724 with the normal register names or the special register names).
1725
1726 This option can also be used for ARM architectures to force the
1727 disassembler to interpret all instructions as Thumb instructions by
1728 using the switch @option{--disassembler-options=force-thumb}. This can be
1729 useful when attempting to disassemble thumb code produced by other
1730 compilers.
1731
1732 For the x86, some of the options duplicate functions of the @option{-m}
1733 switch, but allow finer grained control. Multiple selections from the
1734 following may be specified as a comma separated string.
1735 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1736 the given architecture. @option{intel} and @option{att} select between
1737 intel syntax mode and AT&T syntax mode. @option{addr32},
1738 @option{addr16}, @option{data32} and @option{data16} specify the default
1739 address size and operand size. These four options will be overridden if
1740 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1741 option string. Lastly, @option{suffix}, when in AT&T mode,
1742 instructs the disassembler to print a mnemonic suffix even when the
1743 suffix could be inferred by the operands.
1744
1745 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1746 disassembly of BookE instructions. @option{32} and @option{64} select
1747 PowerPC and PowerPC64 disassembly, respectively.
1748
1749 For MIPS, this option controls the printing of instruction mneumonic
1750 names and register names in disassembled instructions. Multiple
1751 selections from the following may be specified as a comma separated
1752 string, and invalid options are ignored:
1753
1754 @table @code
1755 @item no-aliases
1756 Print the 'raw' instruction mneumonic instead of some pseudo
1757 instruction mneumonic. I.E. print 'daddu' or 'or' instead of 'move',
1758 'sll' instead of 'nop', etc.
1759
1760 @item gpr-names=@var{ABI}
1761 Print GPR (general-purpose register) names as appropriate
1762 for the specified ABI. By default, GPR names are selected according to
1763 the ABI of the binary being disassembled.
1764
1765 @item fpr-names=@var{ABI}
1766 Print FPR (floating-point register) names as
1767 appropriate for the specified ABI. By default, FPR numbers are printed
1768 rather than names.
1769
1770 @item cp0-names=@var{ARCH}
1771 Print CP0 (system control coprocessor; coprocessor 0) register names
1772 as appropriate for the CPU or architecture specified by
1773 @var{ARCH}. By default, CP0 register names are selected according to
1774 the architecture and CPU of the binary being disassembled.
1775
1776 @item hwr-names=@var{ARCH}
1777 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1778 as appropriate for the CPU or architecture specified by
1779 @var{ARCH}. By default, HWR names are selected according to
1780 the architecture and CPU of the binary being disassembled.
1781
1782 @item reg-names=@var{ABI}
1783 Print GPR and FPR names as appropriate for the selected ABI.
1784
1785 @item reg-names=@var{ARCH}
1786 Print CPU-specific register names (CP0 register and HWR names)
1787 as appropriate for the selected CPU or architecture.
1788 @end table
1789
1790 For any of the options listed above, @var{ABI} or
1791 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1792 rather than names, for the selected types of registers.
1793 You can list the available values of @var{ABI} and @var{ARCH} using
1794 the @option{--help} option.
1795
1796 @item -p
1797 @itemx --private-headers
1798 Print information that is specific to the object file format. The exact
1799 information printed depends upon the object file format. For some
1800 object file formats, no additional information is printed.
1801
1802 @item -r
1803 @itemx --reloc
1804 @cindex relocation entries, in object file
1805 Print the relocation entries of the file. If used with @option{-d} or
1806 @option{-D}, the relocations are printed interspersed with the
1807 disassembly.
1808
1809 @item -R
1810 @itemx --dynamic-reloc
1811 @cindex dynamic relocation entries, in object file
1812 Print the dynamic relocation entries of the file. This is only
1813 meaningful for dynamic objects, such as certain types of shared
1814 libraries.
1815
1816 @item -s
1817 @itemx --full-contents
1818 @cindex sections, full contents
1819 @cindex object file sections
1820 Display the full contents of any sections requested. By default all
1821 non-empty sections are displayed.
1822
1823 @item -S
1824 @itemx --source
1825 @cindex source disassembly
1826 @cindex disassembly, with source
1827 Display source code intermixed with disassembly, if possible. Implies
1828 @option{-d}.
1829
1830 @item --show-raw-insn
1831 When disassembling instructions, print the instruction in hex as well as
1832 in symbolic form. This is the default except when
1833 @option{--prefix-addresses} is used.
1834
1835 @item --no-show-raw-insn
1836 When disassembling instructions, do not print the instruction bytes.
1837 This is the default when @option{--prefix-addresses} is used.
1838
1839 @item -G
1840 @itemx --stabs
1841 @cindex stab
1842 @cindex .stab
1843 @cindex debug symbols
1844 @cindex ELF object file format
1845 Display the full contents of any sections requested. Display the
1846 contents of the .stab and .stab.index and .stab.excl sections from an
1847 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1848 @code{.stab} debugging symbol-table entries are carried in an ELF
1849 section. In most other file formats, debugging symbol-table entries are
1850 interleaved with linkage symbols, and are visible in the @option{--syms}
1851 output.
1852 @ifclear man
1853 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1854 Overview,stabs.info, The ``stabs'' debug format}.
1855 @end ifclear
1856
1857 @item --start-address=@var{address}
1858 @cindex start-address
1859 Start displaying data at the specified address. This affects the output
1860 of the @option{-d}, @option{-r} and @option{-s} options.
1861
1862 @item --stop-address=@var{address}
1863 @cindex stop-address
1864 Stop displaying data at the specified address. This affects the output
1865 of the @option{-d}, @option{-r} and @option{-s} options.
1866
1867 @item -t
1868 @itemx --syms
1869 @cindex symbol table entries, printing
1870 Print the symbol table entries of the file.
1871 This is similar to the information provided by the @samp{nm} program.
1872
1873 @item -T
1874 @itemx --dynamic-syms
1875 @cindex dynamic symbol table entries, printing
1876 Print the dynamic symbol table entries of the file. This is only
1877 meaningful for dynamic objects, such as certain types of shared
1878 libraries. This is similar to the information provided by the @samp{nm}
1879 program when given the @option{-D} (@option{--dynamic}) option.
1880
1881 @item --special-syms
1882 When displaying symbols include those which the target considers to be
1883 special in some way and which would not normally be of interest to the
1884 user.
1885
1886 @item -V
1887 @itemx --version
1888 Print the version number of @command{objdump} and exit.
1889
1890 @item -x
1891 @itemx --all-headers
1892 @cindex all header information, object file
1893 @cindex header information, all
1894 Display all available header information, including the symbol table and
1895 relocation entries. Using @option{-x} is equivalent to specifying all of
1896 @option{-a -f -h -p -r -t}.
1897
1898 @item -w
1899 @itemx --wide
1900 @cindex wide output, printing
1901 Format some lines for output devices that have more than 80 columns.
1902 Also do not truncate symbol names when they are displayed.
1903
1904 @item -z
1905 @itemx --disassemble-zeroes
1906 Normally the disassembly output will skip blocks of zeroes. This
1907 option directs the disassembler to disassemble those blocks, just like
1908 any other data.
1909 @end table
1910
1911 @c man end
1912
1913 @ignore
1914 @c man begin SEEALSO objdump
1915 nm(1), readelf(1), and the Info entries for @file{binutils}.
1916 @c man end
1917 @end ignore
1918
1919 @node ranlib
1920 @chapter ranlib
1921
1922 @kindex ranlib
1923 @cindex archive contents
1924 @cindex symbol index
1925
1926 @c man title ranlib generate index to archive.
1927
1928 @smallexample
1929 @c man begin SYNOPSIS ranlib
1930 ranlib [@option{-vV}] @var{archive}
1931 @c man end
1932 @end smallexample
1933
1934 @c man begin DESCRIPTION ranlib
1935
1936 @command{ranlib} generates an index to the contents of an archive and
1937 stores it in the archive. The index lists each symbol defined by a
1938 member of an archive that is a relocatable object file.
1939
1940 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1941
1942 An archive with such an index speeds up linking to the library and
1943 allows routines in the library to call each other without regard to
1944 their placement in the archive.
1945
1946 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1947 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1948 @xref{ar}.
1949
1950 @c man end
1951
1952 @c man begin OPTIONS ranlib
1953
1954 @table @env
1955 @item -v
1956 @itemx -V
1957 @itemx --version
1958 Show the version number of @command{ranlib}.
1959 @end table
1960
1961 @c man end
1962
1963 @ignore
1964 @c man begin SEEALSO ranlib
1965 ar(1), nm(1), and the Info entries for @file{binutils}.
1966 @c man end
1967 @end ignore
1968
1969 @node size
1970 @chapter size
1971
1972 @kindex size
1973 @cindex section sizes
1974
1975 @c man title size list section sizes and total size.
1976
1977 @smallexample
1978 @c man begin SYNOPSIS size
1979 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1980 [@option{--help}]
1981 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1982 [@option{-t}|@option{--totals}]
1983 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1984 [@var{objfile}@dots{}]
1985 @c man end
1986 @end smallexample
1987
1988 @c man begin DESCRIPTION size
1989
1990 The @sc{gnu} @command{size} utility lists the section sizes---and the total
1991 size---for each of the object or archive files @var{objfile} in its
1992 argument list. By default, one line of output is generated for each
1993 object file or each module in an archive.
1994
1995 @var{objfile}@dots{} are the object files to be examined.
1996 If none are specified, the file @code{a.out} will be used.
1997
1998 @c man end
1999
2000 @c man begin OPTIONS size
2001
2002 The command line options have the following meanings:
2003
2004 @table @env
2005 @item -A
2006 @itemx -B
2007 @itemx --format=@var{compatibility}
2008 @cindex @command{size} display format
2009 Using one of these options, you can choose whether the output from @sc{gnu}
2010 @command{size} resembles output from System V @command{size} (using @option{-A},
2011 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2012 @option{--format=berkeley}). The default is the one-line format similar to
2013 Berkeley's.
2014 @c Bonus for doc-source readers: you can also say --format=strange (or
2015 @c anything else that starts with 's') for sysv, and --format=boring (or
2016 @c anything else that starts with 'b') for Berkeley.
2017
2018 Here is an example of the Berkeley (default) format of output from
2019 @command{size}:
2020 @smallexample
2021 $ size --format=Berkeley ranlib size
2022 text data bss dec hex filename
2023 294880 81920 11592 388392 5ed28 ranlib
2024 294880 81920 11888 388688 5ee50 size
2025 @end smallexample
2026
2027 @noindent
2028 This is the same data, but displayed closer to System V conventions:
2029
2030 @smallexample
2031 $ size --format=SysV ranlib size
2032 ranlib :
2033 section size addr
2034 .text 294880 8192
2035 .data 81920 303104
2036 .bss 11592 385024
2037 Total 388392
2038
2039
2040 size :
2041 section size addr
2042 .text 294880 8192
2043 .data 81920 303104
2044 .bss 11888 385024
2045 Total 388688
2046 @end smallexample
2047
2048 @item --help
2049 Show a summary of acceptable arguments and options.
2050
2051 @item -d
2052 @itemx -o
2053 @itemx -x
2054 @itemx --radix=@var{number}
2055 @cindex @command{size} number format
2056 @cindex radix for section sizes
2057 Using one of these options, you can control whether the size of each
2058 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2059 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2060 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2061 values (8, 10, 16) are supported. The total size is always given in two
2062 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2063 octal and hexadecimal if you're using @option{-o}.
2064
2065 @item -t
2066 @itemx --totals
2067 Show totals of all objects listed (Berkeley format listing mode only).
2068
2069 @item --target=@var{bfdname}
2070 @cindex object code format
2071 Specify that the object-code format for @var{objfile} is
2072 @var{bfdname}. This option may not be necessary; @command{size} can
2073 automatically recognize many formats.
2074 @xref{Target Selection}, for more information.
2075
2076 @item -V
2077 @itemx --version
2078 Display the version number of @command{size}.
2079 @end table
2080
2081 @c man end
2082
2083 @ignore
2084 @c man begin SEEALSO size
2085 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2086 @c man end
2087 @end ignore
2088
2089 @node strings
2090 @chapter strings
2091 @kindex strings
2092 @cindex listings strings
2093 @cindex printing strings
2094 @cindex strings, printing
2095
2096 @c man title strings print the strings of printable characters in files.
2097
2098 @smallexample
2099 @c man begin SYNOPSIS strings
2100 strings [@option{-afov}] [@option{-}@var{min-len}]
2101 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2102 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2103 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2104 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2105 [@option{--target=}@var{bfdname}]
2106 [@option{--help}] [@option{--version}] @var{file}@dots{}
2107 @c man end
2108 @end smallexample
2109
2110 @c man begin DESCRIPTION strings
2111
2112 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2113 character sequences that are at least 4 characters long (or the number
2114 given with the options below) and are followed by an unprintable
2115 character. By default, it only prints the strings from the initialized
2116 and loaded sections of object files; for other types of files, it prints
2117 the strings from the whole file.
2118
2119 @command{strings} is mainly useful for determining the contents of non-text
2120 files.
2121
2122 @c man end
2123
2124 @c man begin OPTIONS strings
2125
2126 @table @env
2127 @item -a
2128 @itemx --all
2129 @itemx -
2130 Do not scan only the initialized and loaded sections of object files;
2131 scan the whole files.
2132
2133 @item -f
2134 @itemx --print-file-name
2135 Print the name of the file before each string.
2136
2137 @item --help
2138 Print a summary of the program usage on the standard output and exit.
2139
2140 @item -@var{min-len}
2141 @itemx -n @var{min-len}
2142 @itemx --bytes=@var{min-len}
2143 Print sequences of characters that are at least @var{min-len} characters
2144 long, instead of the default 4.
2145
2146 @item -o
2147 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2148 act like @samp{-t d} instead. Since we can not be compatible with both
2149 ways, we simply chose one.
2150
2151 @item -t @var{radix}
2152 @itemx --radix=@var{radix}
2153 Print the offset within the file before each string. The single
2154 character argument specifies the radix of the offset---@samp{o} for
2155 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2156
2157 @item -e @var{encoding}
2158 @itemx --encoding=@var{encoding}
2159 Select the character encoding of the strings that are to be found.
2160 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2161 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2162 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2163 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2164 littleendian. Useful for finding wide character strings.
2165
2166 @item --target=@var{bfdname}
2167 @cindex object code format
2168 Specify an object code format other than your system's default format.
2169 @xref{Target Selection}, for more information.
2170
2171 @item -v
2172 @itemx --version
2173 Print the program version number on the standard output and exit.
2174 @end table
2175
2176 @c man end
2177
2178 @ignore
2179 @c man begin SEEALSO strings
2180 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2181 and the Info entries for @file{binutils}.
2182 @c man end
2183 @end ignore
2184
2185 @node strip
2186 @chapter strip
2187
2188 @kindex strip
2189 @cindex removing symbols
2190 @cindex discarding symbols
2191 @cindex symbols, discarding
2192
2193 @c man title strip Discard symbols from object files.
2194
2195 @smallexample
2196 @c man begin SYNOPSIS strip
2197 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2198 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2199 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2200 [@option{-s}|@option{--strip-all}]
2201 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2202 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2203 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2204 [@option{-w}|@option{--wildcard}]
2205 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2206 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2207 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2208 [@option{--only-keep-debug}]
2209 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2210 [@option{--help}] [@option{--info}]
2211 @var{objfile}@dots{}
2212 @c man end
2213 @end smallexample
2214
2215 @c man begin DESCRIPTION strip
2216
2217 @sc{gnu} @command{strip} discards all symbols from object files
2218 @var{objfile}. The list of object files may include archives.
2219 At least one object file must be given.
2220
2221 @command{strip} modifies the files named in its argument,
2222 rather than writing modified copies under different names.
2223
2224 @c man end
2225
2226 @c man begin OPTIONS strip
2227
2228 @table @env
2229 @item -F @var{bfdname}
2230 @itemx --target=@var{bfdname}
2231 Treat the original @var{objfile} as a file with the object
2232 code format @var{bfdname}, and rewrite it in the same format.
2233 @xref{Target Selection}, for more information.
2234
2235 @item --help
2236 Show a summary of the options to @command{strip} and exit.
2237
2238 @item --info
2239 Display a list showing all architectures and object formats available.
2240
2241 @item -I @var{bfdname}
2242 @itemx --input-target=@var{bfdname}
2243 Treat the original @var{objfile} as a file with the object
2244 code format @var{bfdname}.
2245 @xref{Target Selection}, for more information.
2246
2247 @item -O @var{bfdname}
2248 @itemx --output-target=@var{bfdname}
2249 Replace @var{objfile} with a file in the output format @var{bfdname}.
2250 @xref{Target Selection}, for more information.
2251
2252 @item -R @var{sectionname}
2253 @itemx --remove-section=@var{sectionname}
2254 Remove any section named @var{sectionname} from the output file. This
2255 option may be given more than once. Note that using this option
2256 inappropriately may make the output file unusable.
2257
2258 @item -s
2259 @itemx --strip-all
2260 Remove all symbols.
2261
2262 @item -g
2263 @itemx -S
2264 @itemx -d
2265 @itemx --strip-debug
2266 Remove debugging symbols only.
2267
2268 @item --strip-unneeded
2269 Remove all symbols that are not needed for relocation processing.
2270
2271 @item -K @var{symbolname}
2272 @itemx --keep-symbol=@var{symbolname}
2273 Keep only symbol @var{symbolname} from the source file. This option may
2274 be given more than once.
2275
2276 @item -N @var{symbolname}
2277 @itemx --strip-symbol=@var{symbolname}
2278 Remove symbol @var{symbolname} from the source file. This option may be
2279 given more than once, and may be combined with strip options other than
2280 @option{-K}.
2281
2282 @item -o @var{file}
2283 Put the stripped output in @var{file}, rather than replacing the
2284 existing file. When this argument is used, only one @var{objfile}
2285 argument may be specified.
2286
2287 @item -p
2288 @itemx --preserve-dates
2289 Preserve the access and modification dates of the file.
2290
2291 @item -w
2292 @itemx --wildcard
2293 Permit regular expressions in @var{symbolname}s used in other command
2294 line options. The question mark (?), asterisk (*), backslash (\) and
2295 square brackets ([]) operators can be used anywhere in the symbol
2296 name. If the first character of the symbol name is the exclamation
2297 point (!) then the sense of the switch is reversed for that symbol.
2298 For example:
2299
2300 @smallexample
2301 -w -K !foo -K fo*
2302 @end smallexample
2303
2304 would cause strip to only keep symbols that start with the letters
2305 ``fo'', but to discard the symbol ``foo''.
2306
2307 @item -x
2308 @itemx --discard-all
2309 Remove non-global symbols.
2310
2311 @item -X
2312 @itemx --discard-locals
2313 Remove compiler-generated local symbols.
2314 (These usually start with @samp{L} or @samp{.}.)
2315
2316 @item --only-keep-debug
2317 Strip a file, removing any sections that would be stripped by
2318 @option{--strip-debug} and leaving the debugging sections.
2319
2320 The intention is that this option will be used in conjunction with
2321 @option{--add-gnu-debuglink} to create a two part executable. One a
2322 stripped binary which will occupy less space in RAM and in a
2323 distribution and the second a debugging information file which is only
2324 needed if debugging abilities are required. The suggested procedure
2325 to create these files is as follows:
2326
2327 @enumerate
2328 @item Link the executable as normal. Assuming that is is called
2329 @code{foo} then...
2330 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2331 create a file containing the debugging info.
2332 @item Run @code{objcopy --strip-debug foo} to create a
2333 stripped executable.
2334 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2335 to add a link to the debugging info into the stripped executable.
2336 @end enumerate
2337
2338 Note - the choice of @code{.dbg} as an extension for the debug info
2339 file is arbitrary. Also the @code{--only-keep-debug} step is
2340 optional. You could instead do this:
2341
2342 @enumerate
2343 @item Link the executable as normal.
2344 @item Copy @code{foo} to @code{foo.full}
2345 @item Run @code{strip --strip-debug foo}
2346 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2347 @end enumerate
2348
2349 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2350 full executable. It does not have to be a file created by the
2351 @option{--only-keep-debug} switch.
2352
2353 @item -V
2354 @itemx --version
2355 Show the version number for @command{strip}.
2356
2357 @item -v
2358 @itemx --verbose
2359 Verbose output: list all object files modified. In the case of
2360 archives, @samp{strip -v} lists all members of the archive.
2361 @end table
2362
2363 @c man end
2364
2365 @ignore
2366 @c man begin SEEALSO strip
2367 the Info entries for @file{binutils}.
2368 @c man end
2369 @end ignore
2370
2371 @node c++filt, addr2line, strip, Top
2372 @chapter c++filt
2373
2374 @kindex c++filt
2375 @cindex demangling C++ symbols
2376
2377 @c man title cxxfilt Demangle C++ and Java symbols.
2378
2379 @smallexample
2380 @c man begin SYNOPSIS cxxfilt
2381 c++filt [@option{-_}|@option{--strip-underscores}]
2382 [@option{-j}|@option{--java}]
2383 [@option{-n}|@option{--no-strip-underscores}]
2384 [@option{-p}|@option{--no-params}]
2385 [@option{-s} @var{format}|@option{--format=}@var{format}]
2386 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2387 @c man end
2388 @end smallexample
2389
2390 @c man begin DESCRIPTION cxxfilt
2391
2392 @kindex cxxfilt
2393 The C++ and Java languages provides function overloading, which means
2394 that you can write many functions with the same name (providing each
2395 takes parameters of different types). All C++ and Java function names
2396 are encoded into a low-level assembly label (this process is known as
2397 @dfn{mangling}). The @command{c++filt}
2398 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2399 MS-DOS this program is named @command{CXXFILT}.}
2400 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2401 names into user-level names so that the linker can keep these overloaded
2402 functions from clashing.
2403
2404 Every alphanumeric word (consisting of letters, digits, underscores,
2405 dollars, or periods) seen in the input is a potential label. If the
2406 label decodes into a C++ name, the C++ name replaces the low-level
2407 name in the output.
2408
2409 You can use @command{c++filt} to decipher individual symbols:
2410
2411 @example
2412 c++filt @var{symbol}
2413 @end example
2414
2415 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2416 names from the standard input and writes the demangled names to the
2417 standard output. All results are printed on the standard output.
2418
2419 @c man end
2420
2421 @c man begin OPTIONS cxxfilt
2422
2423 @table @env
2424 @item -_
2425 @itemx --strip-underscores
2426 On some systems, both the C and C++ compilers put an underscore in front
2427 of every name. For example, the C name @code{foo} gets the low-level
2428 name @code{_foo}. This option removes the initial underscore. Whether
2429 @command{c++filt} removes the underscore by default is target dependent.
2430
2431 @item -j
2432 @itemx --java
2433 Prints demangled names using Java syntax. The default is to use C++
2434 syntax.
2435
2436 @item -n
2437 @itemx --no-strip-underscores
2438 Do not remove the initial underscore.
2439
2440 @item -p
2441 @itemx --no-params
2442 When demangling the name of a function, do not display the types of
2443 the function's parameters.
2444
2445 @item -s @var{format}
2446 @itemx --format=@var{format}
2447 @command{c++filt} can decode various methods of mangling, used by
2448 different compilers. The argument to this option selects which
2449 method it uses:
2450
2451 @table @code
2452 @item auto
2453 Automatic selection based on executable (the default method)
2454 @item gnu
2455 the one used by the @sc{gnu} C++ compiler (g++)
2456 @item lucid
2457 the one used by the Lucid compiler (lcc)
2458 @item arm
2459 the one specified by the C++ Annotated Reference Manual
2460 @item hp
2461 the one used by the HP compiler (aCC)
2462 @item edg
2463 the one used by the EDG compiler
2464 @item gnu-v3
2465 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2466 @item java
2467 the one used by the @sc{gnu} Java compiler (gcj)
2468 @item gnat
2469 the one used by the @sc{gnu} Ada compiler (GNAT).
2470 @end table
2471
2472 @item --help
2473 Print a summary of the options to @command{c++filt} and exit.
2474
2475 @item --version
2476 Print the version number of @command{c++filt} and exit.
2477 @end table
2478
2479 @c man end
2480
2481 @ignore
2482 @c man begin SEEALSO cxxfilt
2483 the Info entries for @file{binutils}.
2484 @c man end
2485 @end ignore
2486
2487 @quotation
2488 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2489 user interface are subject to change in future releases. In particular,
2490 a command-line option may be required in the the future to decode a name
2491 passed as an argument on the command line; in other words,
2492
2493 @example
2494 c++filt @var{symbol}
2495 @end example
2496
2497 @noindent
2498 may in a future release become
2499
2500 @example
2501 c++filt @var{option} @var{symbol}
2502 @end example
2503 @end quotation
2504
2505 @node addr2line
2506 @chapter addr2line
2507
2508 @kindex addr2line
2509 @cindex address to file name and line number
2510
2511 @c man title addr2line convert addresses into file names and line numbers.
2512
2513 @smallexample
2514 @c man begin SYNOPSIS addr2line
2515 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2516 [@option{-C}|@option{--demangle}[=@var{style}]]
2517 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2518 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2519 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2520 [addr addr @dots{}]
2521 @c man end
2522 @end smallexample
2523
2524 @c man begin DESCRIPTION addr2line
2525
2526 @command{addr2line} translates program addresses into file names and line
2527 numbers. Given an address and an executable, it uses the debugging
2528 information in the executable to figure out which file name and line
2529 number are associated with a given address.
2530
2531 The executable to use is specified with the @option{-e} option. The
2532 default is the file @file{a.out}.
2533
2534 @command{addr2line} has two modes of operation.
2535
2536 In the first, hexadecimal addresses are specified on the command line,
2537 and @command{addr2line} displays the file name and line number for each
2538 address.
2539
2540 In the second, @command{addr2line} reads hexadecimal addresses from
2541 standard input, and prints the file name and line number for each
2542 address on standard output. In this mode, @command{addr2line} may be used
2543 in a pipe to convert dynamically chosen addresses.
2544
2545 The format of the output is @samp{FILENAME:LINENO}. The file name and
2546 line number for each address is printed on a separate line. If the
2547 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2548 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2549 containing the address.
2550
2551 If the file name or function name can not be determined,
2552 @command{addr2line} will print two question marks in their place. If the
2553 line number can not be determined, @command{addr2line} will print 0.
2554
2555 @c man end
2556
2557 @c man begin OPTIONS addr2line
2558
2559 The long and short forms of options, shown here as alternatives, are
2560 equivalent.
2561
2562 @table @env
2563 @item -b @var{bfdname}
2564 @itemx --target=@var{bfdname}
2565 @cindex object code format
2566 Specify that the object-code format for the object files is
2567 @var{bfdname}.
2568
2569 @item -C
2570 @itemx --demangle[=@var{style}]
2571 @cindex demangling in objdump
2572 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2573 Besides removing any initial underscore prepended by the system, this
2574 makes C++ function names readable. Different compilers have different
2575 mangling styles. The optional demangling style argument can be used to
2576 choose an appropriate demangling style for your compiler. @xref{c++filt},
2577 for more information on demangling.
2578
2579 @item -e @var{filename}
2580 @itemx --exe=@var{filename}
2581 Specify the name of the executable for which addresses should be
2582 translated. The default file is @file{a.out}.
2583
2584 @item -f
2585 @itemx --functions
2586 Display function names as well as file and line number information.
2587
2588 @item -s
2589 @itemx --basenames
2590 Display only the base of each file name.
2591 @end table
2592
2593 @c man end
2594
2595 @ignore
2596 @c man begin SEEALSO addr2line
2597 Info entries for @file{binutils}.
2598 @c man end
2599 @end ignore
2600
2601 @node nlmconv
2602 @chapter nlmconv
2603
2604 @command{nlmconv} converts a relocatable object file into a NetWare
2605 Loadable Module.
2606
2607 @ignore
2608 @command{nlmconv} currently works with @samp{i386} object
2609 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2610 object files in @sc{elf}, or @code{a.out} format@footnote{
2611 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2612 format in the Binary File Descriptor library. It has only been tested
2613 with the above formats.}.
2614 @end ignore
2615
2616 @quotation
2617 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2618 utilities, since it is only useful for NLM targets.
2619 @end quotation
2620
2621 @c man title nlmconv converts object code into an NLM.
2622
2623 @smallexample
2624 @c man begin SYNOPSIS nlmconv
2625 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2626 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2627 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2628 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2629 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2630 @var{infile} @var{outfile}
2631 @c man end
2632 @end smallexample
2633
2634 @c man begin DESCRIPTION nlmconv
2635
2636 @command{nlmconv} converts the relocatable @samp{i386} object file
2637 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2638 reading @var{headerfile} for NLM header information. For instructions
2639 on writing the NLM command file language used in header files, see the
2640 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2641 Development and Tools Overview}, which is part of the NLM Software
2642 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2643 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2644 @var{infile};
2645 @ifclear man
2646 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2647 @end ifclear
2648
2649 @command{nlmconv} can perform a link step. In other words, you can list
2650 more than one object file for input if you list them in the definitions
2651 file (rather than simply specifying one input file on the command line).
2652 In this case, @command{nlmconv} calls the linker for you.
2653
2654 @c man end
2655
2656 @c man begin OPTIONS nlmconv
2657
2658 @table @env
2659 @item -I @var{bfdname}
2660 @itemx --input-target=@var{bfdname}
2661 Object format of the input file. @command{nlmconv} can usually determine
2662 the format of a given file (so no default is necessary).
2663 @xref{Target Selection}, for more information.
2664
2665 @item -O @var{bfdname}
2666 @itemx --output-target=@var{bfdname}
2667 Object format of the output file. @command{nlmconv} infers the output
2668 format based on the input format, e.g. for a @samp{i386} input file the
2669 output format is @samp{nlm32-i386}.
2670 @xref{Target Selection}, for more information.
2671
2672 @item -T @var{headerfile}
2673 @itemx --header-file=@var{headerfile}
2674 Reads @var{headerfile} for NLM header information. For instructions on
2675 writing the NLM command file language used in header files, see@ see the
2676 @samp{linkers} section, of the @cite{NLM Development and Tools
2677 Overview}, which is part of the NLM Software Developer's Kit, available
2678 from Novell, Inc.
2679
2680 @item -d
2681 @itemx --debug
2682 Displays (on standard error) the linker command line used by @command{nlmconv}.
2683
2684 @item -l @var{linker}
2685 @itemx --linker=@var{linker}
2686 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2687 relative pathname.
2688
2689 @item -h
2690 @itemx --help
2691 Prints a usage summary.
2692
2693 @item -V
2694 @itemx --version
2695 Prints the version number for @command{nlmconv}.
2696 @end table
2697
2698 @c man end
2699
2700 @ignore
2701 @c man begin SEEALSO nlmconv
2702 the Info entries for @file{binutils}.
2703 @c man end
2704 @end ignore
2705
2706 @node windres
2707 @chapter windres
2708
2709 @command{windres} may be used to manipulate Windows resources.
2710
2711 @quotation
2712 @emph{Warning:} @command{windres} is not always built as part of the binary
2713 utilities, since it is only useful for Windows targets.
2714 @end quotation
2715
2716 @c man title windres manipulate Windows resources.
2717
2718 @smallexample
2719 @c man begin SYNOPSIS windres
2720 windres [options] [input-file] [output-file]
2721 @c man end
2722 @end smallexample
2723
2724 @c man begin DESCRIPTION windres
2725
2726 @command{windres} reads resources from an input file and copies them into
2727 an output file. Either file may be in one of three formats:
2728
2729 @table @code
2730 @item rc
2731 A text format read by the Resource Compiler.
2732
2733 @item res
2734 A binary format generated by the Resource Compiler.
2735
2736 @item coff
2737 A COFF object or executable.
2738 @end table
2739
2740 The exact description of these different formats is available in
2741 documentation from Microsoft.
2742
2743 When @command{windres} converts from the @code{rc} format to the @code{res}
2744 format, it is acting like the Windows Resource Compiler. When
2745 @command{windres} converts from the @code{res} format to the @code{coff}
2746 format, it is acting like the Windows @code{CVTRES} program.
2747
2748 When @command{windres} generates an @code{rc} file, the output is similar
2749 but not identical to the format expected for the input. When an input
2750 @code{rc} file refers to an external filename, an output @code{rc} file
2751 will instead include the file contents.
2752
2753 If the input or output format is not specified, @command{windres} will
2754 guess based on the file name, or, for the input file, the file contents.
2755 A file with an extension of @file{.rc} will be treated as an @code{rc}
2756 file, a file with an extension of @file{.res} will be treated as a
2757 @code{res} file, and a file with an extension of @file{.o} or
2758 @file{.exe} will be treated as a @code{coff} file.
2759
2760 If no output file is specified, @command{windres} will print the resources
2761 in @code{rc} format to standard output.
2762
2763 The normal use is for you to write an @code{rc} file, use @command{windres}
2764 to convert it to a COFF object file, and then link the COFF file into
2765 your application. This will make the resources described in the
2766 @code{rc} file available to Windows.
2767
2768 @c man end
2769
2770 @c man begin OPTIONS windres
2771
2772 @table @env
2773 @item -i @var{filename}
2774 @itemx --input @var{filename}
2775 The name of the input file. If this option is not used, then
2776 @command{windres} will use the first non-option argument as the input file
2777 name. If there are no non-option arguments, then @command{windres} will
2778 read from standard input. @command{windres} can not read a COFF file from
2779 standard input.
2780
2781 @item -o @var{filename}
2782 @itemx --output @var{filename}
2783 The name of the output file. If this option is not used, then
2784 @command{windres} will use the first non-option argument, after any used
2785 for the input file name, as the output file name. If there is no
2786 non-option argument, then @command{windres} will write to standard output.
2787 @command{windres} can not write a COFF file to standard output. Note,
2788 for compatability with @command{rc} the option @option{-fo} is also
2789 accepted, but its use is not recommended.
2790
2791 @item -J @var{format}
2792 @itemx --input-format @var{format}
2793 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2794 @samp{coff}. If no input format is specified, @command{windres} will
2795 guess, as described above.
2796
2797 @item -O @var{format}
2798 @itemx --output-format @var{format}
2799 The output format to generate. @var{format} may be @samp{res},
2800 @samp{rc}, or @samp{coff}. If no output format is specified,
2801 @command{windres} will guess, as described above.
2802
2803 @item -F @var{target}
2804 @itemx --target @var{target}
2805 Specify the BFD format to use for a COFF file as input or output. This
2806 is a BFD target name; you can use the @option{--help} option to see a list
2807 of supported targets. Normally @command{windres} will use the default
2808 format, which is the first one listed by the @option{--help} option.
2809 @ifclear man
2810 @ref{Target Selection}.
2811 @end ifclear
2812
2813 @item --preprocessor @var{program}
2814 When @command{windres} reads an @code{rc} file, it runs it through the C
2815 preprocessor first. This option may be used to specify the preprocessor
2816 to use, including any leading arguments. The default preprocessor
2817 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2818
2819 @item -I @var{directory}
2820 @itemx --include-dir @var{directory}
2821 Specify an include directory to use when reading an @code{rc} file.
2822 @command{windres} will pass this to the preprocessor as an @option{-I}
2823 option. @command{windres} will also search this directory when looking for
2824 files named in the @code{rc} file. If the argument passed to this command
2825 matches any of the supported @var{formats} (as descrived in the @option{-J}
2826 option), it will issue a deprecation warning, and behave just like the
2827 @option{-J} option. New programs should not use this behaviour. If a
2828 directory happens to match a @var{format}, simple prefix it with @samp{./}
2829 to disable the backward compatibility.
2830
2831 @item -D @var{target}
2832 @itemx --define @var{sym}[=@var{val}]
2833 Specify a @option{-D} option to pass to the preprocessor when reading an
2834 @code{rc} file.
2835
2836 @item -U @var{target}
2837 @itemx --undefine @var{sym}
2838 Specify a @option{-U} option to pass to the preprocessor when reading an
2839 @code{rc} file.
2840
2841 @item -r
2842 Ignored for compatibility with rc.
2843
2844 @item -v
2845 Enable verbose mode. This tells you what the preprocessor is if you
2846 didn't specify one.
2847
2848 @item -l @var{val}
2849 @item --language @var{val}
2850 Specify the default language to use when reading an @code{rc} file.
2851 @var{val} should be a hexadecimal language code. The low eight bits are
2852 the language, and the high eight bits are the sublanguage.
2853
2854 @item --use-temp-file
2855 Use a temporary file to instead of using popen to read the output of
2856 the preprocessor. Use this option if the popen implementation is buggy
2857 on the host (eg., certain non-English language versions of Windows 95 and
2858 Windows 98 are known to have buggy popen where the output will instead
2859 go the console).
2860
2861 @item --no-use-temp-file
2862 Use popen, not a temporary file, to read the output of the preprocessor.
2863 This is the default behaviour.
2864
2865 @item -h
2866 @item --help
2867 Prints a usage summary.
2868
2869 @item -V
2870 @item --version
2871 Prints the version number for @command{windres}.
2872
2873 @item --yydebug
2874 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2875 this will turn on parser debugging.
2876 @end table
2877
2878 @c man end
2879
2880 @ignore
2881 @c man begin SEEALSO windres
2882 the Info entries for @file{binutils}.
2883 @c man end
2884 @end ignore
2885
2886 @node dlltool
2887 @chapter dlltool
2888 @cindex DLL
2889 @kindex dlltool
2890
2891 @command{dlltool} is used to create the files needed to create dynamic
2892 link libraries (DLLs) on systems which understand PE format image
2893 files such as Windows. A DLL contains an export table which contains
2894 information that the runtime loader needs to resolve references from a
2895 referencing program.
2896
2897 The export table is generated by this program by reading in a
2898 @file{.def} file or scanning the @file{.a} and @file{.o} files which
2899 will be in the DLL. A @file{.o} file can contain information in
2900 special @samp{.drectve} sections with export information.
2901
2902 @quotation
2903 @emph{Note:} @command{dlltool} is not always built as part of the
2904 binary utilities, since it is only useful for those targets which
2905 support DLLs.
2906 @end quotation
2907
2908 @c man title dlltool Create files needed to build and use DLLs.
2909
2910 @smallexample
2911 @c man begin SYNOPSIS dlltool
2912 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2913 [@option{-b}|@option{--base-file} @var{base-file-name}]
2914 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2915 [@option{-z}|@option{--output-def} @var{def-file-name}]
2916 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2917 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2918 [@option{--exclude-symbols} @var{list}]
2919 [@option{--no-default-excludes}]
2920 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2921 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2922 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2923 [@option{-A}|@option{--add-stdcall-alias}]
2924 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
2925 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2926 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
2927 [@option{-v}|@option{--verbose}]
2928 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2929 [object-file @dots{}]
2930 @c man end
2931 @end smallexample
2932
2933 @c man begin DESCRIPTION dlltool
2934
2935 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2936 @option{-b} options as well as object files specified on the command
2937 line. It then processes these inputs and if the @option{-e} option has
2938 been specified it creates a exports file. If the @option{-l} option
2939 has been specified it creates a library file and if the @option{-z} option
2940 has been specified it creates a def file. Any or all of the @option{-e},
2941 @option{-l} and @option{-z} options can be present in one invocation of
2942 dlltool.
2943
2944 When creating a DLL, along with the source for the DLL, it is necessary
2945 to have three other files. @command{dlltool} can help with the creation of
2946 these files.
2947
2948 The first file is a @file{.def} file which specifies which functions are
2949 exported from the DLL, which functions the DLL imports, and so on. This
2950 is a text file and can be created by hand, or @command{dlltool} can be used
2951 to create it using the @option{-z} option. In this case @command{dlltool}
2952 will scan the object files specified on its command line looking for
2953 those functions which have been specially marked as being exported and
2954 put entries for them in the @file{.def} file it creates.
2955
2956 In order to mark a function as being exported from a DLL, it needs to
2957 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2958 section of the object file. This can be done in C by using the
2959 asm() operator:
2960
2961 @smallexample
2962 asm (".section .drectve");
2963 asm (".ascii \"-export:my_func\"");
2964
2965 int my_func (void) @{ @dots{} @}
2966 @end smallexample
2967
2968 The second file needed for DLL creation is an exports file. This file
2969 is linked with the object files that make up the body of the DLL and it
2970 handles the interface between the DLL and the outside world. This is a
2971 binary file and it can be created by giving the @option{-e} option to
2972 @command{dlltool} when it is creating or reading in a @file{.def} file.
2973
2974 The third file needed for DLL creation is the library file that programs
2975 will link with in order to access the functions in the DLL. This file
2976 can be created by giving the @option{-l} option to dlltool when it
2977 is creating or reading in a @file{.def} file.
2978
2979 @command{dlltool} builds the library file by hand, but it builds the
2980 exports file by creating temporary files containing assembler statements
2981 and then assembling these. The @option{-S} command line option can be
2982 used to specify the path to the assembler that dlltool will use,
2983 and the @option{-f} option can be used to pass specific flags to that
2984 assembler. The @option{-n} can be used to prevent dlltool from deleting
2985 these temporary assembler files when it is done, and if @option{-n} is
2986 specified twice then this will prevent dlltool from deleting the
2987 temporary object files it used to build the library.
2988
2989 Here is an example of creating a DLL from a source file @samp{dll.c} and
2990 also creating a program (from an object file called @samp{program.o})
2991 that uses that DLL:
2992
2993 @smallexample
2994 gcc -c dll.c
2995 dlltool -e exports.o -l dll.lib dll.o
2996 gcc dll.o exports.o -o dll.dll
2997 gcc program.o dll.lib -o program
2998 @end smallexample
2999
3000 @c man end
3001
3002 @c man begin OPTIONS dlltool
3003
3004 The command line options have the following meanings:
3005
3006 @table @env
3007
3008 @item -d @var{filename}
3009 @itemx --input-def @var{filename}
3010 @cindex input .def file
3011 Specifies the name of a @file{.def} file to be read in and processed.
3012
3013 @item -b @var{filename}
3014 @itemx --base-file @var{filename}
3015 @cindex base files
3016 Specifies the name of a base file to be read in and processed. The
3017 contents of this file will be added to the relocation section in the
3018 exports file generated by dlltool.
3019
3020 @item -e @var{filename}
3021 @itemx --output-exp @var{filename}
3022 Specifies the name of the export file to be created by dlltool.
3023
3024 @item -z @var{filename}
3025 @itemx --output-def @var{filename}
3026 Specifies the name of the @file{.def} file to be created by dlltool.
3027
3028 @item -l @var{filename}
3029 @itemx --output-lib @var{filename}
3030 Specifies the name of the library file to be created by dlltool.
3031
3032 @item --export-all-symbols
3033 Treat all global and weak defined symbols found in the input object
3034 files as symbols to be exported. There is a small list of symbols which
3035 are not exported by default; see the @option{--no-default-excludes}
3036 option. You may add to the list of symbols to not export by using the
3037 @option{--exclude-symbols} option.
3038
3039 @item --no-export-all-symbols
3040 Only export symbols explicitly listed in an input @file{.def} file or in
3041 @samp{.drectve} sections in the input object files. This is the default
3042 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3043 attributes in the source code.
3044
3045 @item --exclude-symbols @var{list}
3046 Do not export the symbols in @var{list}. This is a list of symbol names
3047 separated by comma or colon characters. The symbol names should not
3048 contain a leading underscore. This is only meaningful when
3049 @option{--export-all-symbols} is used.
3050
3051 @item --no-default-excludes
3052 When @option{--export-all-symbols} is used, it will by default avoid
3053 exporting certain special symbols. The current list of symbols to avoid
3054 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3055 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3056 to go ahead and export these special symbols. This is only meaningful
3057 when @option{--export-all-symbols} is used.
3058
3059 @item -S @var{path}
3060 @itemx --as @var{path}
3061 Specifies the path, including the filename, of the assembler to be used
3062 to create the exports file.
3063
3064 @item -f @var{options}
3065 @itemx --as-flags @var{options}
3066 Specifies any specific command line options to be passed to the
3067 assembler when building the exports file. This option will work even if
3068 the @option{-S} option is not used. This option only takes one argument,
3069 and if it occurs more than once on the command line, then later
3070 occurrences will override earlier occurrences. So if it is necessary to
3071 pass multiple options to the assembler they should be enclosed in
3072 double quotes.
3073
3074 @item -D @var{name}
3075 @itemx --dll-name @var{name}
3076 Specifies the name to be stored in the @file{.def} file as the name of
3077 the DLL when the @option{-e} option is used. If this option is not
3078 present, then the filename given to the @option{-e} option will be
3079 used as the name of the DLL.
3080
3081 @item -m @var{machine}
3082 @itemx -machine @var{machine}
3083 Specifies the type of machine for which the library file should be
3084 built. @command{dlltool} has a built in default type, depending upon how
3085 it was created, but this option can be used to override that. This is
3086 normally only useful when creating DLLs for an ARM processor, when the
3087 contents of the DLL are actually encode using Thumb instructions.
3088
3089 @item -a
3090 @itemx --add-indirect
3091 Specifies that when @command{dlltool} is creating the exports file it
3092 should add a section which allows the exported functions to be
3093 referenced without using the import library. Whatever the hell that
3094 means!
3095
3096 @item -U
3097 @itemx --add-underscore
3098 Specifies that when @command{dlltool} is creating the exports file it
3099 should prepend an underscore to the names of the exported functions.
3100
3101 @item -k
3102 @itemx --kill-at
3103 Specifies that when @command{dlltool} is creating the exports file it
3104 should not append the string @samp{@@ <number>}. These numbers are
3105 called ordinal numbers and they represent another way of accessing the
3106 function in a DLL, other than by name.
3107
3108 @item -A
3109 @itemx --add-stdcall-alias
3110 Specifies that when @command{dlltool} is creating the exports file it
3111 should add aliases for stdcall symbols without @samp{@@ <number>}
3112 in addition to the symbols with @samp{@@ <number>}.
3113
3114 @item -p
3115 @itemx --ext-prefix-alias @var{prefix}
3116 Causes @command{dlltool} to create external aliases for all DLL
3117 imports with the specified prefix. The aliases are created for both
3118 external and import symbols with no leading underscore.
3119
3120 @item -x
3121 @itemx --no-idata4
3122 Specifies that when @command{dlltool} is creating the exports and library
3123 files it should omit the @code{.idata4} section. This is for compatibility
3124 with certain operating systems.
3125
3126 @item -c
3127 @itemx --no-idata5
3128 Specifies that when @command{dlltool} is creating the exports and library
3129 files it should omit the @code{.idata5} section. This is for compatibility
3130 with certain operating systems.
3131
3132 @item -i
3133 @itemx --interwork
3134 Specifies that @command{dlltool} should mark the objects in the library
3135 file and exports file that it produces as supporting interworking
3136 between ARM and Thumb code.
3137
3138 @item -n
3139 @itemx --nodelete
3140 Makes @command{dlltool} preserve the temporary assembler files it used to
3141 create the exports file. If this option is repeated then dlltool will
3142 also preserve the temporary object files it uses to create the library
3143 file.
3144
3145 @item -t @var{prefix}
3146 @itemx --temp-prefix @var{prefix}
3147 Makes @command{dlltool} use @var{prefix} when constructing the names of
3148 temporary assembler and object files. By default, the temp file prefix
3149 is generated from the pid.
3150
3151 @item -v
3152 @itemx --verbose
3153 Make dlltool describe what it is doing.
3154
3155 @item -h
3156 @itemx --help
3157 Displays a list of command line options and then exits.
3158
3159 @item -V
3160 @itemx --version
3161 Displays dlltool's version number and then exits.
3162
3163 @end table
3164
3165 @c man end
3166
3167 @menu
3168 * def file format:: The format of the dlltool @file{.def} file
3169 @end menu
3170
3171 @node def file format
3172 @section The format of the @command{dlltool} @file{.def} file
3173
3174 A @file{.def} file contains any number of the following commands:
3175
3176 @table @asis
3177
3178 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3179 The result is going to be named @var{name}@code{.exe}.
3180
3181 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3182 The result is going to be named @var{name}@code{.dll}.
3183
3184 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3185 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3186 Declares @var{name1} as an exported symbol from the DLL, with optional
3187 ordinal number @var{integer}, or declares @var{name1} as an alias
3188 (forward) of the function @var{external-name} in the DLL
3189 @var{module-name}.
3190
3191 @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{) ) *}
3192 Declares that @var{external-name} or the exported function whose
3193 ordinal number is @var{integer} is to be imported from the file
3194 @var{module-name}. If @var{internal-name} is specified then this is
3195 the name that the imported function will be referred to in the body of
3196 the DLL.
3197
3198 @item @code{DESCRIPTION} @var{string}
3199 Puts @var{string} into the output @file{.exp} file in the
3200 @code{.rdata} section.
3201
3202 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3203 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3204 Generates @code{--stack} or @code{--heap}
3205 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3206 section. The linker will see this and act upon it.
3207
3208 @item @code{CODE} @var{attr} @code{+}
3209 @item @code{DATA} @var{attr} @code{+}
3210 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3211 Generates @code{--attr} @var{section-name} @var{attr} in the output
3212 @code{.drectve} section, where @var{attr} is one of @code{READ},
3213 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3214 this and act upon it.
3215
3216 @end table
3217
3218 @ignore
3219 @c man begin SEEALSO dlltool
3220 The Info pages for @file{binutils}.
3221 @c man end
3222 @end ignore
3223
3224 @node readelf
3225 @chapter readelf
3226
3227 @cindex ELF file information
3228 @kindex readelf
3229
3230 @c man title readelf Displays information about ELF files.
3231
3232 @smallexample
3233 @c man begin SYNOPSIS readelf
3234 readelf [@option{-a}|@option{--all}]
3235 [@option{-h}|@option{--file-header}]
3236 [@option{-l}|@option{--program-headers}|@option{--segments}]
3237 [@option{-S}|@option{--section-headers}|@option{--sections}]
3238 [@option{-e}|@option{--headers}]
3239 [@option{-s}|@option{--syms}|@option{--symbols}]
3240 [@option{-n}|@option{--notes}]
3241 [@option{-r}|@option{--relocs}]
3242 [@option{-u}|@option{--unwind}]
3243 [@option{-d}|@option{--dynamic}]
3244 [@option{-V}|@option{--version-info}]
3245 [@option{-A}|@option{--arch-specific}]
3246 [@option{-D}|@option{--use-dynamic}]
3247 [@option{-x} <number>|@option{--hex-dump=}<number>]
3248 [@option{-w[liaprmfFsoR]}|
3249 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3250 [@option{-I}|@option{-histogram}]
3251 [@option{-v}|@option{--version}]
3252 [@option{-W}|@option{--wide}]
3253 [@option{-H}|@option{--help}]
3254 @var{elffile}@dots{}
3255 @c man end
3256 @end smallexample
3257
3258 @c man begin DESCRIPTION readelf
3259
3260 @command{readelf} displays information about one or more ELF format object
3261 files. The options control what particular information to display.
3262
3263 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3264 64-bit ELF files are supported, as are archives containing ELF files.
3265
3266 This program performs a similar function to @command{objdump} but it
3267 goes into more detail and it exists independently of the @sc{bfd}
3268 library, so if there is a bug in @sc{bfd} then readelf will not be
3269 affected.
3270
3271 @c man end
3272
3273 @c man begin OPTIONS readelf
3274
3275 The long and short forms of options, shown here as alternatives, are
3276 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3277 given.
3278
3279 @table @env
3280 @item -a
3281 @itemx --all
3282 Equivalent to specifiying @option{--file-header},
3283 @option{--program-headers}, @option{--sections}, @option{--symbols},
3284 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3285 @option{--version-info}.
3286
3287 @item -h
3288 @itemx --file-header
3289 @cindex ELF file header information
3290 Displays the information contained in the ELF header at the start of the
3291 file.
3292
3293 @item -l
3294 @itemx --program-headers
3295 @itemx --segments
3296 @cindex ELF program header information
3297 @cindex ELF segment information
3298 Displays the information contained in the file's segment headers, if it
3299 has any.
3300
3301 @item -S
3302 @itemx --sections
3303 @itemx --section-headers
3304 @cindex ELF section information
3305 Displays the information contained in the file's section headers, if it
3306 has any.
3307
3308 @item -s
3309 @itemx --symbols
3310 @itemx --syms
3311 @cindex ELF symbol table information
3312 Displays the entries in symbol table section of the file, if it has one.
3313
3314 @item -e
3315 @itemx --headers
3316 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3317
3318 @item -n
3319 @itemx --notes
3320 @cindex ELF notes
3321 Displays the contents of the NOTE segments and/or sections, if any.
3322
3323 @item -r
3324 @itemx --relocs
3325 @cindex ELF reloc information
3326 Displays the contents of the file's relocation section, if it has one.
3327
3328 @item -u
3329 @itemx --unwind
3330 @cindex unwind information
3331 Displays the contents of the file's unwind section, if it has one. Only
3332 the unwind sections for IA64 ELF files are currently supported.
3333
3334 @item -u
3335 @itemx --unwind
3336 @cindex unwind information
3337 Displays the contents of the file's unwind section, if it has one. Only
3338 the unwind sections for IA64 ELF files are currently supported.
3339
3340 @item -d
3341 @itemx --dynamic
3342 @cindex ELF dynamic section information
3343 Displays the contents of the file's dynamic section, if it has one.
3344
3345 @item -V
3346 @itemx --version-info
3347 @cindex ELF version sections informations
3348 Displays the contents of the version sections in the file, it they
3349 exist.
3350
3351 @item -A
3352 @itemx --arch-specific
3353 Displays architecture-specific information in the file, if there
3354 is any.
3355
3356 @item -D
3357 @itemx --use-dynamic
3358 When displaying symbols, this option makes @command{readelf} use the
3359 symbol table in the file's dynamic section, rather than the one in the
3360 symbols section.
3361
3362 @item -x <number>
3363 @itemx --hex-dump=<number>
3364 Displays the contents of the indicated section as a hexadecimal dump.
3365
3366 @item -w[liaprmfFsoR]
3367 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3368 Displays the contents of the debug sections in the file, if any are
3369 present. If one of the optional letters or words follows the switch
3370 then only data found in those specific sections will be dumped.
3371
3372 @item -I
3373 @itemx --histogram
3374 Display a histogram of bucket list lengths when displaying the contents
3375 of the symbol tables.
3376
3377 @item -v
3378 @itemx --version
3379 Display the version number of readelf.
3380
3381 @item -W
3382 @itemx --wide
3383 Don't break output lines to fit into 80 columns. By default
3384 @command{readelf} breaks section header and segment listing lines for
3385 64-bit ELF files, so that they fit into 80 columns. This option causes
3386 @command{readelf} to print each section header resp. each segment one a
3387 single line, which is far more readable on terminals wider than 80 columns.
3388
3389 @item -H
3390 @itemx --help
3391 Display the command line options understood by @command{readelf}.
3392
3393 @end table
3394
3395 @c man end
3396
3397 @ignore
3398 @c man begin SEEALSO readelf
3399 objdump(1), and the Info entries for @file{binutils}.
3400 @c man end
3401 @end ignore
3402
3403 @node Selecting The Target System
3404 @chapter Selecting the Target System
3405
3406 You can specify two aspects of the target system to the @sc{gnu}
3407 binary file utilities, each in several ways:
3408
3409 @itemize @bullet
3410 @item
3411 the target
3412
3413 @item
3414 the architecture
3415 @end itemize
3416
3417 In the following summaries, the lists of ways to specify values are in
3418 order of decreasing precedence. The ways listed first override those
3419 listed later.
3420
3421 The commands to list valid values only list the values for which the
3422 programs you are running were configured. If they were configured with
3423 @option{--enable-targets=all}, the commands list most of the available
3424 values, but a few are left out; not all targets can be configured in at
3425 once because some of them can only be configured @dfn{native} (on hosts
3426 with the same type as the target system).
3427
3428 @menu
3429 * Target Selection::
3430 * Architecture Selection::
3431 @end menu
3432
3433 @node Target Selection
3434 @section Target Selection
3435
3436 A @dfn{target} is an object file format. A given target may be
3437 supported for multiple architectures (@pxref{Architecture Selection}).
3438 A target selection may also have variations for different operating
3439 systems or architectures.
3440
3441 The command to list valid target values is @samp{objdump -i}
3442 (the first column of output contains the relevant information).
3443
3444 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3445 @samp{a.out-sunos-big}.
3446
3447 You can also specify a target using a configuration triplet. This is
3448 the same sort of name that is passed to @file{configure} to specify a
3449 target. When you use a configuration triplet as an argument, it must be
3450 fully canonicalized. You can see the canonical version of a triplet by
3451 running the shell script @file{config.sub} which is included with the
3452 sources.
3453
3454 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3455 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3456
3457 @subheading @command{objdump} Target
3458
3459 Ways to specify:
3460
3461 @enumerate
3462 @item
3463 command line option: @option{-b} or @option{--target}
3464
3465 @item
3466 environment variable @code{GNUTARGET}
3467
3468 @item
3469 deduced from the input file
3470 @end enumerate
3471
3472 @subheading @command{objcopy} and @command{strip} Input Target
3473
3474 Ways to specify:
3475
3476 @enumerate
3477 @item
3478 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3479
3480 @item
3481 environment variable @code{GNUTARGET}
3482
3483 @item
3484 deduced from the input file
3485 @end enumerate
3486
3487 @subheading @command{objcopy} and @command{strip} Output Target
3488
3489 Ways to specify:
3490
3491 @enumerate
3492 @item
3493 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3494
3495 @item
3496 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3497
3498 @item
3499 environment variable @code{GNUTARGET}
3500
3501 @item
3502 deduced from the input file
3503 @end enumerate
3504
3505 @subheading @command{nm}, @command{size}, and @command{strings} Target
3506
3507 Ways to specify:
3508
3509 @enumerate
3510 @item
3511 command line option: @option{--target}
3512
3513 @item
3514 environment variable @code{GNUTARGET}
3515
3516 @item
3517 deduced from the input file
3518 @end enumerate
3519
3520 @node Architecture Selection
3521 @section Architecture Selection
3522
3523 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3524 to run. Its name may contain a colon, separating the name of the
3525 processor family from the name of the particular @sc{cpu}.
3526
3527 The command to list valid architecture values is @samp{objdump -i} (the
3528 second column contains the relevant information).
3529
3530 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3531
3532 @subheading @command{objdump} Architecture
3533
3534 Ways to specify:
3535
3536 @enumerate
3537 @item
3538 command line option: @option{-m} or @option{--architecture}
3539
3540 @item
3541 deduced from the input file
3542 @end enumerate
3543
3544 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3545
3546 Ways to specify:
3547
3548 @enumerate
3549 @item
3550 deduced from the input file
3551 @end enumerate
3552
3553 @node Reporting Bugs
3554 @chapter Reporting Bugs
3555 @cindex bugs
3556 @cindex reporting bugs
3557
3558 Your bug reports play an essential role in making the binary utilities
3559 reliable.
3560
3561 Reporting a bug may help you by bringing a solution to your problem, or
3562 it may not. But in any case the principal function of a bug report is
3563 to help the entire community by making the next version of the binary
3564 utilities work better. Bug reports are your contribution to their
3565 maintenance.
3566
3567 In order for a bug report to serve its purpose, you must include the
3568 information that enables us to fix the bug.
3569
3570 @menu
3571 * Bug Criteria:: Have you found a bug?
3572 * Bug Reporting:: How to report bugs
3573 @end menu
3574
3575 @node Bug Criteria
3576 @section Have You Found a Bug?
3577 @cindex bug criteria
3578
3579 If you are not sure whether you have found a bug, here are some guidelines:
3580
3581 @itemize @bullet
3582 @cindex fatal signal
3583 @cindex crash
3584 @item
3585 If a binary utility gets a fatal signal, for any input whatever, that is
3586 a bug. Reliable utilities never crash.
3587
3588 @cindex error on valid input
3589 @item
3590 If a binary utility produces an error message for valid input, that is a
3591 bug.
3592
3593 @item
3594 If you are an experienced user of binary utilities, your suggestions for
3595 improvement are welcome in any case.
3596 @end itemize
3597
3598 @node Bug Reporting
3599 @section How to Report Bugs
3600 @cindex bug reports
3601 @cindex bugs, reporting
3602
3603 A number of companies and individuals offer support for @sc{gnu}
3604 products. If you obtained the binary utilities from a support
3605 organization, we recommend you contact that organization first.
3606
3607 You can find contact information for many support companies and
3608 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3609 distribution.
3610
3611 In any event, we also recommend that you send bug reports for the binary
3612 utilities to @samp{bug-binutils@@gnu.org}.
3613
3614 The fundamental principle of reporting bugs usefully is this:
3615 @strong{report all the facts}. If you are not sure whether to state a
3616 fact or leave it out, state it!
3617
3618 Often people omit facts because they think they know what causes the
3619 problem and assume that some details do not matter. Thus, you might
3620 assume that the name of a file you use in an example does not matter.
3621 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3622 a stray memory reference which happens to fetch from the location where
3623 that pathname is stored in memory; perhaps, if the pathname were
3624 different, the contents of that location would fool the utility into
3625 doing the right thing despite the bug. Play it safe and give a
3626 specific, complete example. That is the easiest thing for you to do,
3627 and the most helpful.
3628
3629 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3630 it is new to us. Therefore, always write your bug reports on the assumption
3631 that the bug has not been reported previously.
3632
3633 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3634 bell?'' This cannot help us fix a bug, so it is basically useless. We
3635 respond by asking for enough details to enable us to investigate.
3636 You might as well expedite matters by sending them to begin with.
3637
3638 To enable us to fix the bug, you should include all these things:
3639
3640 @itemize @bullet
3641 @item
3642 The version of the utility. Each utility announces it if you start it
3643 with the @option{--version} argument.
3644
3645 Without this, we will not know whether there is any point in looking for
3646 the bug in the current version of the binary utilities.
3647
3648 @item
3649 Any patches you may have applied to the source, including any patches
3650 made to the @code{BFD} library.
3651
3652 @item
3653 The type of machine you are using, and the operating system name and
3654 version number.
3655
3656 @item
3657 What compiler (and its version) was used to compile the utilities---e.g.
3658 ``@code{gcc-2.7}''.
3659
3660 @item
3661 The command arguments you gave the utility to observe the bug. To
3662 guarantee you will not omit something important, list them all. A copy
3663 of the Makefile (or the output from make) is sufficient.
3664
3665 If we were to try to guess the arguments, we would probably guess wrong
3666 and then we might not encounter the bug.
3667
3668 @item
3669 A complete input file, or set of input files, that will reproduce the
3670 bug. If the utility is reading an object file or files, then it is
3671 generally most helpful to send the actual object files, uuencoded if
3672 necessary to get them through the mail system. Note that
3673 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3674 sending very large files to it. Making the files available for
3675 anonymous FTP is OK.
3676
3677 If the source files were produced exclusively using @sc{gnu} programs
3678 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3679 may be OK to send the source files rather than the object files. In
3680 this case, be sure to say exactly what version of @command{gcc}, or
3681 whatever, was used to produce the object files. Also say how
3682 @command{gcc}, or whatever, was configured.
3683
3684 @item
3685 A description of what behavior you observe that you believe is
3686 incorrect. For example, ``It gets a fatal signal.''
3687
3688 Of course, if the bug is that the utility gets a fatal signal, then we
3689 will certainly notice it. But if the bug is incorrect output, we might
3690 not notice unless it is glaringly wrong. You might as well not give us
3691 a chance to make a mistake.
3692
3693 Even if the problem you experience is a fatal signal, you should still
3694 say so explicitly. Suppose something strange is going on, such as your
3695 copy of the utility is out of synch, or you have encountered a bug in
3696 the C library on your system. (This has happened!) Your copy might
3697 crash and ours would not. If you told us to expect a crash, then when
3698 ours fails to crash, we would know that the bug was not happening for
3699 us. If you had not told us to expect a crash, then we would not be able
3700 to draw any conclusion from our observations.
3701
3702 @item
3703 If you wish to suggest changes to the source, send us context diffs, as
3704 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3705 option. Always send diffs from the old file to the new file. If you
3706 wish to discuss something in the @command{ld} source, refer to it by
3707 context, not by line number.
3708
3709 The line numbers in our development sources will not match those in your
3710 sources. Your line numbers would convey no useful information to us.
3711 @end itemize
3712
3713 Here are some things that are not necessary:
3714
3715 @itemize @bullet
3716 @item
3717 A description of the envelope of the bug.
3718
3719 Often people who encounter a bug spend a lot of time investigating
3720 which changes to the input file will make the bug go away and which
3721 changes will not affect it.
3722
3723 This is often time consuming and not very useful, because the way we
3724 will find the bug is by running a single example under the debugger
3725 with breakpoints, not by pure deduction from a series of examples.
3726 We recommend that you save your time for something else.
3727
3728 Of course, if you can find a simpler example to report @emph{instead}
3729 of the original one, that is a convenience for us. Errors in the
3730 output will be easier to spot, running under the debugger will take
3731 less time, and so on.
3732
3733 However, simplification is not vital; if you do not want to do this,
3734 report the bug anyway and send us the entire test case you used.
3735
3736 @item
3737 A patch for the bug.
3738
3739 A patch for the bug does help us if it is a good one. But do not omit
3740 the necessary information, such as the test case, on the assumption that
3741 a patch is all we need. We might see problems with your patch and decide
3742 to fix the problem another way, or we might not understand it at all.
3743
3744 Sometimes with programs as complicated as the binary utilities it is
3745 very hard to construct an example that will make the program follow a
3746 certain path through the code. If you do not send us the example, we
3747 will not be able to construct one, so we will not be able to verify that
3748 the bug is fixed.
3749
3750 And if we cannot understand what bug you are trying to fix, or why your
3751 patch should be an improvement, we will not install it. A test case will
3752 help us to understand.
3753
3754 @item
3755 A guess about what the bug is or what it depends on.
3756
3757 Such guesses are usually wrong. Even we cannot guess right about such
3758 things without first using the debugger to find the facts.
3759 @end itemize
3760
3761 @include fdl.texi
3762
3763 @node Index
3764 @unnumbered Index
3765
3766 @printindex cp
3767
3768 @contents
3769 @bye
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