1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2015 Free Software Foundation, Inc.
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
25 @dircategory Software development
27 * Binutils: (binutils). The GNU binary utilities.
30 @dircategory Individual utilities
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nlmconv: (binutils)nlmconv. Converts object code into an NLM.
38 * nm: (binutils)nm. List symbols from object files.
39 * objcopy: (binutils)objcopy. Copy and translate object files.
40 * objdump: (binutils)objdump. Display information from object files.
41 * ranlib: (binutils)ranlib. Generate index to archive contents.
42 * readelf: (binutils)readelf. Display the contents of ELF format files.
43 * size: (binutils)size. List section sizes and total size.
44 * strings: (binutils)strings. List printable strings from files.
45 * strip: (binutils)strip. Discard symbols.
46 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
47 * windmc: (binutils)windmc. Generator for Windows message resources.
48 * windres: (binutils)windres. Manipulate Windows resources.
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
56 @subtitle Version @value{VERSION}
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
69 @vskip 0pt plus 1filll
78 This brief manual contains documentation for the @sc{gnu} binary
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
83 version @value{VERSION}:
88 Create, modify, and extract from archives
91 List symbols from object files
94 Copy and translate object files
97 Display information from object files
100 Generate index to archive contents
103 Display the contents of ELF format files.
106 List file section sizes and total size
109 List printable strings from files
115 Update the ELF header of ELF files.
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
122 Convert addresses into file names and line numbers
125 Convert object code into a Netware Loadable Module
128 Manipulate Windows resources
131 Generator for Windows message resources
134 Create the files needed to build and use Dynamic Link Libraries
138 This document is distributed under the terms of the GNU Free
139 Documentation License version 1.3. A copy of the license is included
140 in the section entitled ``GNU Free Documentation License''.
143 * ar:: Create, modify, and extract from archives
144 * nm:: List symbols from object files
145 * objcopy:: Copy and translate object files
146 * objdump:: Display information from object files
147 * ranlib:: Generate index to archive contents
148 * size:: List section sizes and total size
149 * strings:: List printable strings from files
150 * strip:: Discard symbols
151 * c++filt:: Filter to demangle encoded C++ symbols
152 * cxxfilt: c++filt. MS-DOS name for c++filt
153 * addr2line:: Convert addresses to file and line
154 * nlmconv:: Converts object code into an NLM
155 * windmc:: Generator for Windows message resources
156 * windres:: Manipulate Windows resources
157 * dlltool:: Create files needed to build and use DLLs
158 * readelf:: Display the contents of ELF format files
159 * elfedit:: Update the ELF header of ELF files
160 * Common Options:: Command-line options for all utilities
161 * Selecting the Target System:: How these utilities determine the target
162 * Reporting Bugs:: Reporting Bugs
163 * GNU Free Documentation License:: GNU Free Documentation License
164 * Binutils Index:: Binutils Index
172 @cindex collections of files
174 @c man title ar create, modify, and extract from archives
177 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
178 ar -M [ <mri-script ]
181 @c man begin DESCRIPTION ar
183 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
193 @sc{gnu} @command{ar} can maintain archives whose members have names of any
194 length; however, depending on how @command{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @command{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @command{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @command{ar} called
216 @command{ranlib} can be used to add just the table.
218 @cindex thin archives
219 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
220 which contains a symbol index and references to the original copies
221 of the member files of the archive. This is useful for building
222 libraries for use within a local build tree, where the relocatable
223 objects are expected to remain available, and copying the contents of
224 each object would only waste time and space.
226 An archive can either be @emph{thin} or it can be normal. It cannot
227 be both at the same time. Once an archive is created its format
228 cannot be changed without first deleting it and then creating a new
229 archive in its place.
231 Thin archives are also @emph{flattened}, so that adding one thin
232 archive to another thin archive does not nest it, as would happen with
233 a normal archive. Instead the elements of the first archive are added
234 individually to the second archive.
236 The paths to the elements of the archive are stored relative to the
237 archive itself. For security reasons absolute paths and paths with a
238 @code{/../} component are not allowed.
240 @cindex compatibility, @command{ar}
241 @cindex @command{ar} compatibility
242 @sc{gnu} @command{ar} is designed to be compatible with two different
243 facilities. You can control its activity using command-line options,
244 like the different varieties of @command{ar} on Unix systems; or, if you
245 specify the single command-line option @option{-M}, you can control it
246 with a script supplied via standard input, like the MRI ``librarian''
252 * ar cmdline:: Controlling @command{ar} on the command line
253 * ar scripts:: Controlling @command{ar} with a script
258 @section Controlling @command{ar} on the Command Line
261 @c man begin SYNOPSIS ar
262 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
266 @cindex Unix compatibility, @command{ar}
267 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
268 arguments to execute: one keyletter specifying the @emph{operation}
269 (optionally accompanied by other keyletters specifying
270 @emph{modifiers}), and the archive name to act on.
272 Most operations can also accept further @var{member} arguments,
273 specifying particular files to operate on.
275 @c man begin OPTIONS ar
277 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
278 flags @var{mod} in any order, within the first command-line argument.
280 If you wish, you may begin the first command-line argument with a
283 @cindex operations on archive
284 The @var{p} keyletter specifies what operation to execute; it may be
285 any of the following, but you must specify only one of them:
289 @cindex deleting from archive
290 @emph{Delete} modules from the archive. Specify the names of modules to
291 be deleted as @var{member}@dots{}; the archive is untouched if you
292 specify no files to delete.
294 If you specify the @samp{v} modifier, @command{ar} lists each module
298 @cindex moving in archive
299 Use this operation to @emph{move} members in an archive.
301 The ordering of members in an archive can make a difference in how
302 programs are linked using the library, if a symbol is defined in more
305 If no modifiers are used with @code{m}, any members you name in the
306 @var{member} arguments are moved to the @emph{end} of the archive;
307 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
308 specified place instead.
311 @cindex printing from archive
312 @emph{Print} the specified members of the archive, to the standard
313 output file. If the @samp{v} modifier is specified, show the member
314 name before copying its contents to standard output.
316 If you specify no @var{member} arguments, all the files in the archive are
320 @cindex quick append to archive
321 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
322 @var{archive}, without checking for replacement.
324 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
325 operation; new members are always placed at the end of the archive.
327 The modifier @samp{v} makes @command{ar} list each file as it is appended.
329 Since the point of this operation is speed, implementations of
330 @command{ar} have the option of not updating the archive's symbol
331 table if one exists. Too many different systems however assume that
332 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
333 rebuild the table even with a quick append.
335 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
336 synonym for @samp{r} - replacing already existing files in the
337 archive and appending new ones at the end.
340 @cindex replacement in archive
341 Insert the files @var{member}@dots{} into @var{archive} (with
342 @emph{replacement}). This operation differs from @samp{q} in that any
343 previously existing members are deleted if their names match those being
346 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
347 displays an error message, and leaves undisturbed any existing members
348 of the archive matching that name.
350 By default, new members are added at the end of the file; but you may
351 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
352 placement relative to some existing member.
354 The modifier @samp{v} used with this operation elicits a line of
355 output for each file inserted, along with one of the letters @samp{a} or
356 @samp{r} to indicate whether the file was appended (no old member
357 deleted) or replaced.
361 Add an index to the archive, or update it if it already exists. Note
362 this command is an exception to the rule that there can only be one
363 command letter, as it is possible to use it as either a command or a
364 modifier. In either case it does the same thing.
367 @cindex contents of archive
368 Display a @emph{table} listing the contents of @var{archive}, or those
369 of the files listed in @var{member}@dots{} that are present in the
370 archive. Normally only the member name is shown; if you also want to
371 see the modes (permissions), timestamp, owner, group, and size, you can
372 request that by also specifying the @samp{v} modifier.
374 If you do not specify a @var{member}, all files in the archive
377 @cindex repeated names in archive
378 @cindex name duplication in archive
379 If there is more than one file with the same name (say, @samp{fie}) in
380 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
381 first instance; to see them all, you must ask for a complete
382 listing---in our example, @samp{ar t b.a}.
383 @c WRS only; per Gumby, this is implementation-dependent, and in a more
384 @c recent case in fact works the other way.
387 @cindex extract from archive
388 @emph{Extract} members (named @var{member}) from the archive. You can
389 use the @samp{v} modifier with this operation, to request that
390 @command{ar} list each name as it extracts it.
392 If you do not specify a @var{member}, all files in the archive
395 Files cannot be extracted from a thin archive.
398 Displays the list of command line options supported by @command{ar}
402 Displays the version information of @command{ar} and then exits.
406 A number of modifiers (@var{mod}) may immediately follow the @var{p}
407 keyletter, to specify variations on an operation's behavior:
411 @cindex relative placement in archive
412 Add new files @emph{after} an existing member of the
413 archive. If you use the modifier @samp{a}, the name of an existing archive
414 member must be present as the @var{relpos} argument, before the
415 @var{archive} specification.
418 Add new files @emph{before} an existing member of the
419 archive. If you use the modifier @samp{b}, the name of an existing archive
420 member must be present as the @var{relpos} argument, before the
421 @var{archive} specification. (same as @samp{i}).
424 @cindex creating archives
425 @emph{Create} the archive. The specified @var{archive} is always
426 created if it did not exist, when you request an update. But a warning is
427 issued unless you specify in advance that you expect to create it, by
431 @cindex deterministic archives
432 @kindex --enable-deterministic-archives
433 Operate in @emph{deterministic} mode. When adding files and the archive
434 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
435 for all files. When this option is used, if @command{ar} is used with
436 identical options and identical input files, multiple runs will create
437 identical output files regardless of the input files' owners, groups,
438 file modes, or modification times.
440 If @file{binutils} was configured with
441 @option{--enable-deterministic-archives}, then this mode is on by default.
442 It can be disabled with the @samp{U} modifier, below.
445 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
446 names of any length. This will cause it to create archives which are
447 not compatible with the native @command{ar} program on some systems. If
448 this is a concern, the @samp{f} modifier may be used to truncate file
449 names when putting them in the archive.
452 Insert new files @emph{before} an existing member of the
453 archive. If you use the modifier @samp{i}, the name of an existing archive
454 member must be present as the @var{relpos} argument, before the
455 @var{archive} specification. (same as @samp{b}).
458 This modifier is accepted but not used.
459 @c whaffor ar l modifier??? presumably compat; with
460 @c what???---doc@@cygnus.com, 25jan91
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
474 Use the full path name when matching names in the archive. @sc{gnu}
475 @command{ar} can not create an archive with a full path name (such archives
476 are not POSIX complaint), but other archive creators can. This option
477 will cause @sc{gnu} @command{ar} to match file names using a complete path
478 name, which can be convenient when extracting a single file from an
479 archive created by another tool.
482 @cindex writing archive index
483 Write an object-file index into the archive, or update an existing one,
484 even if no other change is made to the archive. You may use this modifier
485 flag either with any operation, or alone. Running @samp{ar s} on an
486 archive is equivalent to running @samp{ranlib} on it.
489 @cindex not writing archive index
490 Do not generate an archive symbol table. This can speed up building a
491 large library in several steps. The resulting archive can not be used
492 with the linker. In order to build a symbol table, you must omit the
493 @samp{S} modifier on the last execution of @samp{ar}, or you must run
494 @samp{ranlib} on the archive.
497 @cindex creating thin archive
498 Make the specified @var{archive} a @emph{thin} archive. If it already
499 exists and is a regular archive, the existing members must be present
500 in the same directory as @var{archive}.
503 @cindex updating an archive
504 Normally, @samp{ar r}@dots{} inserts all files
505 listed into the archive. If you would like to insert @emph{only} those
506 of the files you list that are newer than existing members of the same
507 names, use this modifier. The @samp{u} modifier is allowed only for the
508 operation @samp{r} (replace). In particular, the combination @samp{qu} is
509 not allowed, since checking the timestamps would lose any speed
510 advantage from the operation @samp{q}.
513 @cindex deterministic archives
514 @kindex --enable-deterministic-archives
515 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
516 of the @samp{D} modifier, above: added files and the archive index will
517 get their actual UID, GID, timestamp, and file mode values.
519 This is the default unless @file{binutils} was configured with
520 @option{--enable-deterministic-archives}.
523 This modifier requests the @emph{verbose} version of an operation. Many
524 operations display additional information, such as filenames processed,
525 when the modifier @samp{v} is appended.
528 This modifier shows the version number of @command{ar}.
531 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
532 compatibility with AIX. The behaviour produced by this option is the
533 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
534 @samp{-X} options; in particular, it does not support @option{-X32}
535 which is the default for AIX @command{ar}.
537 The optional command line switch @option{--plugin} @var{name} causes
538 @command{ar} to load the plugin called @var{name} which adds support
539 for more file formats. This option is only available if the toolchain
540 has been built with plugin support enabled.
542 The optional command line switch @option{--target} @var{bfdname}
543 specifies that the archive members are in an object code format
544 different from your system's default format. See
545 @xref{Target Selection}, for more information.
550 @c man begin SEEALSO ar
551 nm(1), ranlib(1), and the Info entries for @file{binutils}.
556 @section Controlling @command{ar} with a Script
559 ar -M [ <@var{script} ]
562 @cindex MRI compatibility, @command{ar}
563 @cindex scripts, @command{ar}
564 If you use the single command-line option @samp{-M} with @command{ar}, you
565 can control its operation with a rudimentary command language. This
566 form of @command{ar} operates interactively if standard input is coming
567 directly from a terminal. During interactive use, @command{ar} prompts for
568 input (the prompt is @samp{AR >}), and continues executing even after
569 errors. If you redirect standard input to a script file, no prompts are
570 issued, and @command{ar} abandons execution (with a nonzero exit code)
573 The @command{ar} command language is @emph{not} designed to be equivalent
574 to the command-line options; in fact, it provides somewhat less control
575 over archives. The only purpose of the command language is to ease the
576 transition to @sc{gnu} @command{ar} for developers who already have scripts
577 written for the MRI ``librarian'' program.
579 The syntax for the @command{ar} command language is straightforward:
582 commands are recognized in upper or lower case; for example, @code{LIST}
583 is the same as @code{list}. In the following descriptions, commands are
584 shown in upper case for clarity.
587 a single command may appear on each line; it is the first word on the
591 empty lines are allowed, and have no effect.
594 comments are allowed; text after either of the characters @samp{*}
595 or @samp{;} is ignored.
598 Whenever you use a list of names as part of the argument to an @command{ar}
599 command, you can separate the individual names with either commas or
600 blanks. Commas are shown in the explanations below, for clarity.
603 @samp{+} is used as a line continuation character; if @samp{+} appears
604 at the end of a line, the text on the following line is considered part
605 of the current command.
608 Here are the commands you can use in @command{ar} scripts, or when using
609 @command{ar} interactively. Three of them have special significance:
611 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
612 a temporary file required for most of the other commands.
614 @code{SAVE} commits the changes so far specified by the script. Prior
615 to @code{SAVE}, commands affect only the temporary copy of the current
619 @item ADDLIB @var{archive}
620 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
621 Add all the contents of @var{archive} (or, if specified, each named
622 @var{module} from @var{archive}) to the current archive.
624 Requires prior use of @code{OPEN} or @code{CREATE}.
626 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
627 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
628 @c else like "ar q..."
629 Add each named @var{member} as a module in the current archive.
631 Requires prior use of @code{OPEN} or @code{CREATE}.
634 Discard the contents of the current archive, canceling the effect of
635 any operations since the last @code{SAVE}. May be executed (with no
636 effect) even if no current archive is specified.
638 @item CREATE @var{archive}
639 Creates an archive, and makes it the current archive (required for many
640 other commands). The new archive is created with a temporary name; it
641 is not actually saved as @var{archive} until you use @code{SAVE}.
642 You can overwrite existing archives; similarly, the contents of any
643 existing file named @var{archive} will not be destroyed until @code{SAVE}.
645 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
646 Delete each listed @var{module} from the current archive; equivalent to
647 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
649 Requires prior use of @code{OPEN} or @code{CREATE}.
651 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
652 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
653 List each named @var{module} present in @var{archive}. The separate
654 command @code{VERBOSE} specifies the form of the output: when verbose
655 output is off, output is like that of @samp{ar -t @var{archive}
656 @var{module}@dots{}}. When verbose output is on, the listing is like
657 @samp{ar -tv @var{archive} @var{module}@dots{}}.
659 Output normally goes to the standard output stream; however, if you
660 specify @var{outputfile} as a final argument, @command{ar} directs the
664 Exit from @command{ar}, with a @code{0} exit code to indicate successful
665 completion. This command does not save the output file; if you have
666 changed the current archive since the last @code{SAVE} command, those
669 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
670 Extract each named @var{module} from the current archive, writing them
671 into the current directory as separate files. Equivalent to @samp{ar -x
672 @var{archive} @var{module}@dots{}}.
674 Requires prior use of @code{OPEN} or @code{CREATE}.
677 @c FIXME Tokens but no commands???
684 Display full contents of the current archive, in ``verbose'' style
685 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
686 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
687 enhancement, rather than present for MRI compatibility.)
689 Requires prior use of @code{OPEN} or @code{CREATE}.
691 @item OPEN @var{archive}
692 Opens an existing archive for use as the current archive (required for
693 many other commands). Any changes as the result of subsequent commands
694 will not actually affect @var{archive} until you next use @code{SAVE}.
696 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
697 In the current archive, replace each existing @var{module} (named in
698 the @code{REPLACE} arguments) from files in the current working directory.
699 To execute this command without errors, both the file, and the module in
700 the current archive, must exist.
702 Requires prior use of @code{OPEN} or @code{CREATE}.
705 Toggle an internal flag governing the output from @code{DIRECTORY}.
706 When the flag is on, @code{DIRECTORY} output matches output from
707 @samp{ar -tv }@dots{}.
710 Commit your changes to the current archive, and actually save it as a
711 file with the name specified in the last @code{CREATE} or @code{OPEN}
714 Requires prior use of @code{OPEN} or @code{CREATE}.
723 The @sc{gnu} linker @command{ld} is now described in a separate manual.
724 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
732 @c man title nm list symbols from object files
735 @c man begin SYNOPSIS nm
736 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
737 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
738 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
739 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
740 [@option{-l}|@option{--line-numbers}] [@option{-n}|@option{-v}|@option{--numeric-sort}]
741 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
742 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
743 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
744 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
745 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
746 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
747 [@option{--synthetic}] [@option{--target=}@var{bfdname}]
748 [@var{objfile}@dots{}]
752 @c man begin DESCRIPTION nm
753 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
754 If no object files are listed as arguments, @command{nm} assumes the file
757 For each symbol, @command{nm} shows:
761 The symbol value, in the radix selected by options (see below), or
762 hexadecimal by default.
765 The symbol type. At least the following types are used; others are, as
766 well, depending on the object file format. If lowercase, the symbol is
767 usually local; if uppercase, the symbol is global (external). There
768 are however a few lowercase symbols that are shown for special global
769 symbols (@code{u}, @code{v} and @code{w}).
771 @c Some more detail on exactly what these symbol types are used for
775 The symbol's value is absolute, and will not be changed by further
780 The symbol is in the uninitialized data section (known as BSS).
783 The symbol is common. Common symbols are uninitialized data. When
784 linking, multiple common symbols may appear with the same name. If the
785 symbol is defined anywhere, the common symbols are treated as undefined
788 For more details on common symbols, see the discussion of
789 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
794 The symbol is in the initialized data section.
798 The symbol is in an initialized data section for small objects. Some
799 object file formats permit more efficient access to small data objects,
800 such as a global int variable as opposed to a large global array.
803 For PE format files this indicates that the symbol is in a section
804 specific to the implementation of DLLs. For ELF format files this
805 indicates that the symbol is an indirect function. This is a GNU
806 extension to the standard set of ELF symbol types. It indicates a
807 symbol which if referenced by a relocation does not evaluate to its
808 address, but instead must be invoked at runtime. The runtime
809 execution will then return the value to be used in the relocation.
812 The symbol is an indirect reference to another symbol.
815 The symbol is a debugging symbol.
818 The symbols is in a stack unwind section.
822 The symbol is in a read only data section.
826 The symbol is in an uninitialized data section for small objects.
830 The symbol is in the text (code) section.
833 The symbol is undefined.
836 The symbol is a unique global symbol. This is a GNU extension to the
837 standard set of ELF symbol bindings. For such a symbol the dynamic linker
838 will make sure that in the entire process there is just one symbol with
839 this name and type in use.
843 The symbol is a weak object. When a weak defined symbol is linked with
844 a normal defined symbol, the normal defined symbol is used with no error.
845 When a weak undefined symbol is linked and the symbol is not defined,
846 the value of the weak symbol becomes zero with no error. On some
847 systems, uppercase indicates that a default value has been specified.
851 The symbol is a weak symbol that has not been specifically tagged as a
852 weak object symbol. When a weak defined symbol is linked with a normal
853 defined symbol, the normal defined symbol is used with no error.
854 When a weak undefined symbol is linked and the symbol is not defined,
855 the value of the symbol is determined in a system-specific manner without
856 error. On some systems, uppercase indicates that a default value has been
860 The symbol is a stabs symbol in an a.out object file. In this case, the
861 next values printed are the stabs other field, the stabs desc field, and
862 the stab type. Stabs symbols are used to hold debugging information.
865 The symbol type is unknown, or object file format specific.
874 @c man begin OPTIONS nm
875 The long and short forms of options, shown here as alternatives, are
881 @itemx --print-file-name
882 @cindex input file name
884 @cindex source file name
885 Precede each symbol by the name of the input file (or archive member)
886 in which it was found, rather than identifying the input file once only,
887 before all of its symbols.
891 @cindex debugging symbols
892 Display all symbols, even debugger-only symbols; normally these are not
896 @cindex @command{nm} format
897 @cindex @command{nm} compatibility
898 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
901 @itemx --demangle[=@var{style}]
902 @cindex demangling in nm
903 Decode (@dfn{demangle}) low-level symbol names into user-level names.
904 Besides removing any initial underscore prepended by the system, this
905 makes C++ function names readable. Different compilers have different
906 mangling styles. The optional demangling style argument can be used to
907 choose an appropriate demangling style for your compiler. @xref{c++filt},
908 for more information on demangling.
911 Do not demangle low-level symbol names. This is the default.
915 @cindex dynamic symbols
916 Display the dynamic symbols rather than the normal symbols. This is
917 only meaningful for dynamic objects, such as certain types of shared
920 @item -f @var{format}
921 @itemx --format=@var{format}
922 @cindex @command{nm} format
923 @cindex @command{nm} compatibility
924 Use the output format @var{format}, which can be @code{bsd},
925 @code{sysv}, or @code{posix}. The default is @code{bsd}.
926 Only the first character of @var{format} is significant; it can be
927 either upper or lower case.
931 @cindex external symbols
932 Display only external symbols.
936 Show a summary of the options to @command{nm} and exit.
939 @itemx --line-numbers
940 @cindex symbol line numbers
941 For each symbol, use debugging information to try to find a filename and
942 line number. For a defined symbol, look for the line number of the
943 address of the symbol. For an undefined symbol, look for the line
944 number of a relocation entry which refers to the symbol. If line number
945 information can be found, print it after the other symbol information.
949 @itemx --numeric-sort
950 Sort symbols numerically by their addresses, rather than alphabetically
955 @cindex sorting symbols
956 Do not bother to sort the symbols in any order; print them in the order
961 Use the POSIX.2 standard output format instead of the default format.
962 Equivalent to @samp{-f posix}.
965 @itemx --reverse-sort
966 Reverse the order of the sort (whether numeric or alphabetic); let the
971 Print both value and size of defined symbols for the @code{bsd} output style.
972 This option has no effect for object formats that do not record symbol
973 sizes, unless @samp{--size-sort} is also used in which case a
974 calculated size is displayed.
978 @cindex symbol index, listing
979 When listing symbols from archive members, include the index: a mapping
980 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
981 contain definitions for which names.
984 @itemx --radix=@var{radix}
985 Use @var{radix} as the radix for printing the symbol values. It must be
986 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
989 @itemx --undefined-only
990 @cindex external symbols
991 @cindex undefined symbols
992 Display only undefined symbols (those external to each object file).
996 Show the version number of @command{nm} and exit.
999 This option is ignored for compatibility with the AIX version of
1000 @command{nm}. It takes one parameter which must be the string
1001 @option{32_64}. The default mode of AIX @command{nm} corresponds
1002 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1004 @item --defined-only
1005 @cindex external symbols
1006 @cindex undefined symbols
1007 Display only defined symbols for each object file.
1009 @item --plugin @var{name}
1011 Load the plugin called @var{name} to add support for extra target
1012 types. This option is only available if the toolchain has been built
1013 with plugin support enabled.
1016 Sort symbols by size. The size is computed as the difference between
1017 the value of the symbol and the value of the symbol with the next higher
1018 value. If the @code{bsd} output format is used the size of the symbol
1019 is printed, rather than the value, and @samp{-S} must be used in order
1020 both size and value to be printed.
1022 @item --special-syms
1023 Display symbols which have a target-specific special meaning. These
1024 symbols are usually used by the target for some special processing and
1025 are not normally helpful when included in the normal symbol lists.
1026 For example for ARM targets this option would skip the mapping symbols
1027 used to mark transitions between ARM code, THUMB code and data.
1030 Include synthetic symbols in the output. These are special symbols
1031 created by the linker for various purposes. They are not shown by
1032 default since they are not part of the binary's original source code.
1034 @item --target=@var{bfdname}
1035 @cindex object code format
1036 Specify an object code format other than your system's default format.
1037 @xref{Target Selection}, for more information.
1044 @c man begin SEEALSO nm
1045 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1052 @c man title objcopy copy and translate object files
1055 @c man begin SYNOPSIS objcopy
1056 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1057 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1058 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1059 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1060 [@option{-S}|@option{--strip-all}]
1061 [@option{-g}|@option{--strip-debug}]
1062 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1063 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1064 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1065 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1066 [@option{--localize-hidden}]
1067 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1068 [@option{--globalize-symbol=}@var{symbolname}]
1069 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1070 [@option{-w}|@option{--wildcard}]
1071 [@option{-x}|@option{--discard-all}]
1072 [@option{-X}|@option{--discard-locals}]
1073 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1074 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1075 [@option{--interleave-width=}@var{width}]
1076 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1077 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1078 [@option{-p}|@option{--preserve-dates}]
1079 [@option{-D}|@option{--enable-deterministic-archives}]
1080 [@option{-U}|@option{--disable-deterministic-archives}]
1081 [@option{--debugging}]
1082 [@option{--gap-fill=}@var{val}]
1083 [@option{--pad-to=}@var{address}]
1084 [@option{--set-start=}@var{val}]
1085 [@option{--adjust-start=}@var{incr}]
1086 [@option{--change-addresses=}@var{incr}]
1087 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1088 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1089 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1090 [@option{--change-warnings}] [@option{--no-change-warnings}]
1091 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1092 [@option{--add-section} @var{sectionname}=@var{filename}]
1093 [@option{--dump-section} @var{sectionname}=@var{filename}]
1094 [@option{--update-section} @var{sectionname}=@var{filename}]
1095 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1096 [@option{--long-section-names} @{enable,disable,keep@}]
1097 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1098 [@option{--reverse-bytes=}@var{num}]
1099 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1100 [@option{--redefine-sym} @var{old}=@var{new}]
1101 [@option{--redefine-syms=}@var{filename}]
1103 [@option{--keep-symbols=}@var{filename}]
1104 [@option{--strip-symbols=}@var{filename}]
1105 [@option{--strip-unneeded-symbols=}@var{filename}]
1106 [@option{--keep-global-symbols=}@var{filename}]
1107 [@option{--localize-symbols=}@var{filename}]
1108 [@option{--globalize-symbols=}@var{filename}]
1109 [@option{--weaken-symbols=}@var{filename}]
1110 [@option{--alt-machine-code=}@var{index}]
1111 [@option{--prefix-symbols=}@var{string}]
1112 [@option{--prefix-sections=}@var{string}]
1113 [@option{--prefix-alloc-sections=}@var{string}]
1114 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1115 [@option{--keep-file-symbols}]
1116 [@option{--only-keep-debug}]
1117 [@option{--strip-dwo}]
1118 [@option{--extract-dwo}]
1119 [@option{--extract-symbol}]
1120 [@option{--writable-text}]
1121 [@option{--readonly-text}]
1124 [@option{--file-alignment=}@var{num}]
1125 [@option{--heap=}@var{size}]
1126 [@option{--image-base=}@var{address}]
1127 [@option{--section-alignment=}@var{num}]
1128 [@option{--stack=}@var{size}]
1129 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1130 [@option{--compress-debug-sections}]
1131 [@option{--decompress-debug-sections}]
1132 [@option{--dwarf-depth=@var{n}}]
1133 [@option{--dwarf-start=@var{n}}]
1134 [@option{-v}|@option{--verbose}]
1135 [@option{-V}|@option{--version}]
1136 [@option{--help}] [@option{--info}]
1137 @var{infile} [@var{outfile}]
1141 @c man begin DESCRIPTION objcopy
1142 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1143 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1144 read and write the object files. It can write the destination object
1145 file in a format different from that of the source object file. The
1146 exact behavior of @command{objcopy} is controlled by command-line options.
1147 Note that @command{objcopy} should be able to copy a fully linked file
1148 between any two formats. However, copying a relocatable object file
1149 between any two formats may not work as expected.
1151 @command{objcopy} creates temporary files to do its translations and
1152 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1153 translation work; it has access to all the formats described in @sc{bfd}
1154 and thus is able to recognize most formats without being told
1155 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1157 @command{objcopy} can be used to generate S-records by using an output
1158 target of @samp{srec} (e.g., use @samp{-O srec}).
1160 @command{objcopy} can be used to generate a raw binary file by using an
1161 output target of @samp{binary} (e.g., use @option{-O binary}). When
1162 @command{objcopy} generates a raw binary file, it will essentially produce
1163 a memory dump of the contents of the input object file. All symbols and
1164 relocation information will be discarded. The memory dump will start at
1165 the load address of the lowest section copied into the output file.
1167 When generating an S-record or a raw binary file, it may be helpful to
1168 use @option{-S} to remove sections containing debugging information. In
1169 some cases @option{-R} will be useful to remove sections which contain
1170 information that is not needed by the binary file.
1172 Note---@command{objcopy} is not able to change the endianness of its input
1173 files. If the input format has an endianness (some formats do not),
1174 @command{objcopy} can only copy the inputs into file formats that have the
1175 same endianness or which have no endianness (e.g., @samp{srec}).
1176 (However, see the @option{--reverse-bytes} option.)
1180 @c man begin OPTIONS objcopy
1184 @itemx @var{outfile}
1185 The input and output files, respectively.
1186 If you do not specify @var{outfile}, @command{objcopy} creates a
1187 temporary file and destructively renames the result with
1188 the name of @var{infile}.
1190 @item -I @var{bfdname}
1191 @itemx --input-target=@var{bfdname}
1192 Consider the source file's object format to be @var{bfdname}, rather than
1193 attempting to deduce it. @xref{Target Selection}, for more information.
1195 @item -O @var{bfdname}
1196 @itemx --output-target=@var{bfdname}
1197 Write the output file using the object format @var{bfdname}.
1198 @xref{Target Selection}, for more information.
1200 @item -F @var{bfdname}
1201 @itemx --target=@var{bfdname}
1202 Use @var{bfdname} as the object format for both the input and the output
1203 file; i.e., simply transfer data from source to destination with no
1204 translation. @xref{Target Selection}, for more information.
1206 @item -B @var{bfdarch}
1207 @itemx --binary-architecture=@var{bfdarch}
1208 Useful when transforming a architecture-less input file into an object file.
1209 In this case the output architecture can be set to @var{bfdarch}. This
1210 option will be ignored if the input file has a known @var{bfdarch}. You
1211 can access this binary data inside a program by referencing the special
1212 symbols that are created by the conversion process. These symbols are
1213 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1214 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1215 an object file and then access it in your code using these symbols.
1217 @item -j @var{sectionpattern}
1218 @itemx --only-section=@var{sectionpattern}
1219 Copy only the indicated sections from the input file to the output file.
1220 This option may be given more than once. Note that using this option
1221 inappropriately may make the output file unusable. Wildcard
1222 characters are accepted in @var{sectionpattern}.
1224 @item -R @var{sectionpattern}
1225 @itemx --remove-section=@var{sectionpattern}
1226 Remove any section matching @var{sectionpattern} from the output file.
1227 This option may be given more than once. Note that using this option
1228 inappropriately may make the output file unusable. Wildcard
1229 characters are accepted in @var{sectionpattern}. Using both the
1230 @option{-j} and @option{-R} options together results in undefined
1235 Do not copy relocation and symbol information from the source file.
1238 @itemx --strip-debug
1239 Do not copy debugging symbols or sections from the source file.
1241 @item --strip-unneeded
1242 Strip all symbols that are not needed for relocation processing.
1244 @item -K @var{symbolname}
1245 @itemx --keep-symbol=@var{symbolname}
1246 When stripping symbols, keep symbol @var{symbolname} even if it would
1247 normally be stripped. This option may be given more than once.
1249 @item -N @var{symbolname}
1250 @itemx --strip-symbol=@var{symbolname}
1251 Do not copy symbol @var{symbolname} from the source file. This option
1252 may be given more than once.
1254 @item --strip-unneeded-symbol=@var{symbolname}
1255 Do not copy symbol @var{symbolname} from the source file unless it is needed
1256 by a relocation. This option may be given more than once.
1258 @item -G @var{symbolname}
1259 @itemx --keep-global-symbol=@var{symbolname}
1260 Keep only symbol @var{symbolname} global. Make all other symbols local
1261 to the file, so that they are not visible externally. This option may
1262 be given more than once.
1264 @item --localize-hidden
1265 In an ELF object, mark all symbols that have hidden or internal visibility
1266 as local. This option applies on top of symbol-specific localization options
1267 such as @option{-L}.
1269 @item -L @var{symbolname}
1270 @itemx --localize-symbol=@var{symbolname}
1271 Make symbol @var{symbolname} local to the file, so that it is not
1272 visible externally. This option may be given more than once.
1274 @item -W @var{symbolname}
1275 @itemx --weaken-symbol=@var{symbolname}
1276 Make symbol @var{symbolname} weak. This option may be given more than once.
1278 @item --globalize-symbol=@var{symbolname}
1279 Give symbol @var{symbolname} global scoping so that it is visible
1280 outside of the file in which it is defined. This option may be given
1285 Permit regular expressions in @var{symbolname}s used in other command
1286 line options. The question mark (?), asterisk (*), backslash (\) and
1287 square brackets ([]) operators can be used anywhere in the symbol
1288 name. If the first character of the symbol name is the exclamation
1289 point (!) then the sense of the switch is reversed for that symbol.
1296 would cause objcopy to weaken all symbols that start with ``fo''
1297 except for the symbol ``foo''.
1300 @itemx --discard-all
1301 Do not copy non-global symbols from the source file.
1302 @c FIXME any reason to prefer "non-global" to "local" here?
1305 @itemx --discard-locals
1306 Do not copy compiler-generated local symbols.
1307 (These usually start with @samp{L} or @samp{.}.)
1310 @itemx --byte=@var{byte}
1311 If interleaving has been enabled via the @option{--interleave} option
1312 then start the range of bytes to keep at the @var{byte}th byte.
1313 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1314 @var{breadth} is the value given by the @option{--interleave} option.
1316 @item -i [@var{breadth}]
1317 @itemx --interleave[=@var{breadth}]
1318 Only copy a range out of every @var{breadth} bytes. (Header data is
1319 not affected). Select which byte in the range begins the copy with
1320 the @option{--byte} option. Select the width of the range with the
1321 @option{--interleave-width} option.
1323 This option is useful for creating files to program @sc{rom}. It is
1324 typically used with an @code{srec} output target. Note that
1325 @command{objcopy} will complain if you do not specify the
1326 @option{--byte} option as well.
1328 The default interleave breadth is 4, so with @option{--byte} set to 0,
1329 @command{objcopy} would copy the first byte out of every four bytes
1330 from the input to the output.
1332 @item --interleave-width=@var{width}
1333 When used with the @option{--interleave} option, copy @var{width}
1334 bytes at a time. The start of the range of bytes to be copied is set
1335 by the @option{--byte} option, and the extent of the range is set with
1336 the @option{--interleave} option.
1338 The default value for this option is 1. The value of @var{width} plus
1339 the @var{byte} value set by the @option{--byte} option must not exceed
1340 the interleave breadth set by the @option{--interleave} option.
1342 This option can be used to create images for two 16-bit flashes interleaved
1343 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1344 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1345 commands. If the input was '12345678' then the outputs would be
1346 '1256' and '3478' respectively.
1349 @itemx --preserve-dates
1350 Set the access and modification dates of the output file to be the same
1351 as those of the input file.
1354 @itemx --enable-deterministic-archives
1355 @cindex deterministic archives
1356 @kindex --enable-deterministic-archives
1357 Operate in @emph{deterministic} mode. When copying archive members
1358 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1359 and use consistent file modes for all files.
1361 If @file{binutils} was configured with
1362 @option{--enable-deterministic-archives}, then this mode is on by default.
1363 It can be disabled with the @samp{-U} option, below.
1366 @itemx --disable-deterministic-archives
1367 @cindex deterministic archives
1368 @kindex --enable-deterministic-archives
1369 Do @emph{not} operate in @emph{deterministic} mode. This is the
1370 inverse of the @option{-D} option, above: when copying archive members
1371 and writing the archive index, use their actual UID, GID, timestamp,
1372 and file mode values.
1374 This is the default unless @file{binutils} was configured with
1375 @option{--enable-deterministic-archives}.
1378 Convert debugging information, if possible. This is not the default
1379 because only certain debugging formats are supported, and the
1380 conversion process can be time consuming.
1382 @item --gap-fill @var{val}
1383 Fill gaps between sections with @var{val}. This operation applies to
1384 the @emph{load address} (LMA) of the sections. It is done by increasing
1385 the size of the section with the lower address, and filling in the extra
1386 space created with @var{val}.
1388 @item --pad-to @var{address}
1389 Pad the output file up to the load address @var{address}. This is
1390 done by increasing the size of the last section. The extra space is
1391 filled in with the value specified by @option{--gap-fill} (default zero).
1393 @item --set-start @var{val}
1394 Set the start address of the new file to @var{val}. Not all object file
1395 formats support setting the start address.
1397 @item --change-start @var{incr}
1398 @itemx --adjust-start @var{incr}
1399 @cindex changing start address
1400 Change the start address by adding @var{incr}. Not all object file
1401 formats support setting the start address.
1403 @item --change-addresses @var{incr}
1404 @itemx --adjust-vma @var{incr}
1405 @cindex changing object addresses
1406 Change the VMA and LMA addresses of all sections, as well as the start
1407 address, by adding @var{incr}. Some object file formats do not permit
1408 section addresses to be changed arbitrarily. Note that this does not
1409 relocate the sections; if the program expects sections to be loaded at a
1410 certain address, and this option is used to change the sections such
1411 that they are loaded at a different address, the program may fail.
1413 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1414 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1415 @cindex changing section address
1416 Set or change both the VMA address and the LMA address of any section
1417 matching @var{sectionpattern}. If @samp{=} is used, the section
1418 address is set to @var{val}. Otherwise, @var{val} is added to or
1419 subtracted from the section address. See the comments under
1420 @option{--change-addresses}, above. If @var{sectionpattern} does not
1421 match any sections in the input file, a warning will be issued, unless
1422 @option{--no-change-warnings} is used.
1424 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1425 @cindex changing section LMA
1426 Set or change the LMA address of any sections matching
1427 @var{sectionpattern}. The LMA address is the address where the
1428 section will be loaded into memory at program load time. Normally
1429 this is the same as the VMA address, which is the address of the
1430 section at program run time, but on some systems, especially those
1431 where a program is held in ROM, the two can be different. If @samp{=}
1432 is used, the section address is set to @var{val}. Otherwise,
1433 @var{val} is added to or subtracted from the section address. See the
1434 comments under @option{--change-addresses}, above. If
1435 @var{sectionpattern} does not match any sections in the input file, a
1436 warning will be issued, unless @option{--no-change-warnings} is used.
1438 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1439 @cindex changing section VMA
1440 Set or change the VMA address of any section matching
1441 @var{sectionpattern}. The VMA address is the address where the
1442 section will be located once the program has started executing.
1443 Normally this is the same as the LMA address, which is the address
1444 where the section will be loaded into memory, but on some systems,
1445 especially those where a program is held in ROM, the two can be
1446 different. If @samp{=} is used, the section address is set to
1447 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1448 section address. See the comments under @option{--change-addresses},
1449 above. If @var{sectionpattern} does not match any sections in the
1450 input file, a warning will be issued, unless
1451 @option{--no-change-warnings} is used.
1453 @item --change-warnings
1454 @itemx --adjust-warnings
1455 If @option{--change-section-address} or @option{--change-section-lma} or
1456 @option{--change-section-vma} is used, and the section pattern does not
1457 match any sections, issue a warning. This is the default.
1459 @item --no-change-warnings
1460 @itemx --no-adjust-warnings
1461 Do not issue a warning if @option{--change-section-address} or
1462 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1463 if the section pattern does not match any sections.
1465 @item --set-section-flags @var{sectionpattern}=@var{flags}
1466 Set the flags for any sections matching @var{sectionpattern}. The
1467 @var{flags} argument is a comma separated string of flag names. The
1468 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1469 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1470 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1471 for a section which does not have contents, but it is not meaningful
1472 to clear the @samp{contents} flag of a section which does have
1473 contents--just remove the section instead. Not all flags are
1474 meaningful for all object file formats.
1476 @item --add-section @var{sectionname}=@var{filename}
1477 Add a new section named @var{sectionname} while copying the file. The
1478 contents of the new section are taken from the file @var{filename}. The
1479 size of the section will be the size of the file. This option only
1480 works on file formats which can support sections with arbitrary names.
1481 Note - it may be necessary to use the @option{--set-section-flags}
1482 option to set the attributes of the newly created section.
1484 @item --dump-section @var{sectionname}=@var{filename}
1485 Place the contents of section named @var{sectionname} into the file
1486 @var{filename}, overwriting any contents that may have been there
1487 previously. This option is the inverse of @option{--add-section}.
1488 This option is similar to the @option{--only-section} option except
1489 that it does not create a formatted file, it just dumps the contents
1490 as raw binary data, without applying any relocations. The option can
1491 be specified more than once.
1493 @item --update-section @var{sectionname}=@var{filename}
1494 Replace the existing contents of a section named @var{sectionname}
1495 with the contents of file @var{filename}. The size of the section
1496 will be adjusted to the size of the file. The section flags for
1497 @var{sectionname} will be unchanged. For ELF format files the section
1498 to segment mapping will also remain unchanged, something which is not
1499 possible using @option{--remove-section} followed by
1500 @option{--add-section}. The option can be specified more than once.
1502 Note - it is possible to use @option{--rename-section} and
1503 @option{--update-section} to both update and rename a section from one
1504 command line. In this case, pass the original section name to
1505 @option{--update-section}, and the original and new section names to
1506 @option{--rename-section}.
1508 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1509 Rename a section from @var{oldname} to @var{newname}, optionally
1510 changing the section's flags to @var{flags} in the process. This has
1511 the advantage over usng a linker script to perform the rename in that
1512 the output stays as an object file and does not become a linked
1515 This option is particularly helpful when the input format is binary,
1516 since this will always create a section called .data. If for example,
1517 you wanted instead to create a section called .rodata containing binary
1518 data you could use the following command line to achieve it:
1521 objcopy -I binary -O <output_format> -B <architecture> \
1522 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1523 <input_binary_file> <output_object_file>
1526 @item --long-section-names @{enable,disable,keep@}
1527 Controls the handling of long section names when processing @code{COFF}
1528 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1529 is to preserve long section names if any are present in the input file.
1530 The @samp{enable} and @samp{disable} options forcibly enable or disable
1531 the use of long section names in the output object; when @samp{disable}
1532 is in effect, any long section names in the input object will be truncated.
1533 The @samp{enable} option will only emit long section names if any are
1534 present in the inputs; this is mostly the same as @samp{keep}, but it
1535 is left undefined whether the @samp{enable} option might force the
1536 creation of an empty string table in the output file.
1538 @item --change-leading-char
1539 Some object file formats use special characters at the start of
1540 symbols. The most common such character is underscore, which compilers
1541 often add before every symbol. This option tells @command{objcopy} to
1542 change the leading character of every symbol when it converts between
1543 object file formats. If the object file formats use the same leading
1544 character, this option has no effect. Otherwise, it will add a
1545 character, or remove a character, or change a character, as
1548 @item --remove-leading-char
1549 If the first character of a global symbol is a special symbol leading
1550 character used by the object file format, remove the character. The
1551 most common symbol leading character is underscore. This option will
1552 remove a leading underscore from all global symbols. This can be useful
1553 if you want to link together objects of different file formats with
1554 different conventions for symbol names. This is different from
1555 @option{--change-leading-char} because it always changes the symbol name
1556 when appropriate, regardless of the object file format of the output
1559 @item --reverse-bytes=@var{num}
1560 Reverse the bytes in a section with output contents. A section length must
1561 be evenly divisible by the value given in order for the swap to be able to
1562 take place. Reversing takes place before the interleaving is performed.
1564 This option is used typically in generating ROM images for problematic
1565 target systems. For example, on some target boards, the 32-bit words
1566 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1567 regardless of the CPU byte order. Depending on the programming model, the
1568 endianness of the ROM may need to be modified.
1570 Consider a simple file with a section containing the following eight
1571 bytes: @code{12345678}.
1573 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1574 output file would be ordered @code{21436587}.
1576 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1577 output file would be ordered @code{43218765}.
1579 By using @samp{--reverse-bytes=2} for the above example, followed by
1580 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1581 output file would be ordered @code{34127856}.
1583 @item --srec-len=@var{ival}
1584 Meaningful only for srec output. Set the maximum length of the Srecords
1585 being produced to @var{ival}. This length covers both address, data and
1588 @item --srec-forceS3
1589 Meaningful only for srec output. Avoid generation of S1/S2 records,
1590 creating S3-only record format.
1592 @item --redefine-sym @var{old}=@var{new}
1593 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1594 when one is trying link two things together for which you have no
1595 source, and there are name collisions.
1597 @item --redefine-syms=@var{filename}
1598 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1599 listed in the file @var{filename}. @var{filename} is simply a flat file,
1600 with one symbol pair per line. Line comments may be introduced by the hash
1601 character. This option may be given more than once.
1604 Change all global symbols in the file to be weak. This can be useful
1605 when building an object which will be linked against other objects using
1606 the @option{-R} option to the linker. This option is only effective when
1607 using an object file format which supports weak symbols.
1609 @item --keep-symbols=@var{filename}
1610 Apply @option{--keep-symbol} option to each symbol listed in the file
1611 @var{filename}. @var{filename} is simply a flat file, with one symbol
1612 name per line. Line comments may be introduced by the hash character.
1613 This option may be given more than once.
1615 @item --strip-symbols=@var{filename}
1616 Apply @option{--strip-symbol} option to each symbol listed in the file
1617 @var{filename}. @var{filename} is simply a flat file, with one symbol
1618 name per line. Line comments may be introduced by the hash character.
1619 This option may be given more than once.
1621 @item --strip-unneeded-symbols=@var{filename}
1622 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1623 the file @var{filename}. @var{filename} is simply a flat file, with one
1624 symbol name per line. Line comments may be introduced by the hash
1625 character. This option may be given more than once.
1627 @item --keep-global-symbols=@var{filename}
1628 Apply @option{--keep-global-symbol} option to each symbol listed in the
1629 file @var{filename}. @var{filename} is simply a flat file, with one
1630 symbol name per line. Line comments may be introduced by the hash
1631 character. This option may be given more than once.
1633 @item --localize-symbols=@var{filename}
1634 Apply @option{--localize-symbol} option to each symbol listed in the file
1635 @var{filename}. @var{filename} is simply a flat file, with one symbol
1636 name per line. Line comments may be introduced by the hash character.
1637 This option may be given more than once.
1639 @item --globalize-symbols=@var{filename}
1640 Apply @option{--globalize-symbol} option to each symbol listed in the file
1641 @var{filename}. @var{filename} is simply a flat file, with one symbol
1642 name per line. Line comments may be introduced by the hash character.
1643 This option may be given more than once.
1645 @item --weaken-symbols=@var{filename}
1646 Apply @option{--weaken-symbol} option to each symbol listed in the file
1647 @var{filename}. @var{filename} is simply a flat file, with one symbol
1648 name per line. Line comments may be introduced by the hash character.
1649 This option may be given more than once.
1651 @item --alt-machine-code=@var{index}
1652 If the output architecture has alternate machine codes, use the
1653 @var{index}th code instead of the default one. This is useful in case
1654 a machine is assigned an official code and the tool-chain adopts the
1655 new code, but other applications still depend on the original code
1656 being used. For ELF based architectures if the @var{index}
1657 alternative does not exist then the value is treated as an absolute
1658 number to be stored in the e_machine field of the ELF header.
1660 @item --writable-text
1661 Mark the output text as writable. This option isn't meaningful for all
1662 object file formats.
1664 @item --readonly-text
1665 Make the output text write protected. This option isn't meaningful for all
1666 object file formats.
1669 Mark the output file as demand paged. This option isn't meaningful for all
1670 object file formats.
1673 Mark the output file as impure. This option isn't meaningful for all
1674 object file formats.
1676 @item --prefix-symbols=@var{string}
1677 Prefix all symbols in the output file with @var{string}.
1679 @item --prefix-sections=@var{string}
1680 Prefix all section names in the output file with @var{string}.
1682 @item --prefix-alloc-sections=@var{string}
1683 Prefix all the names of all allocated sections in the output file with
1686 @item --add-gnu-debuglink=@var{path-to-file}
1687 Creates a .gnu_debuglink section which contains a reference to
1688 @var{path-to-file} and adds it to the output file. Note: the file at
1689 @var{path-to-file} must exist. Part of the process of adding the
1690 .gnu_debuglink section involves embedding a checksum of the contents
1691 of the debug info file into the section.
1693 If the debug info file is built in one location but it is going to be
1694 installed at a later time into a different location then do not use
1695 the path to the installed location. The @option{--add-gnu-debuglink}
1696 option will fail because the installed file does not exist yet.
1697 Instead put the debug info file in the current directory and use the
1698 @option{--add-gnu-debuglink} option without any directory components,
1702 objcopy --add-gnu-debuglink=foo.debug
1705 At debug time the debugger will attempt to look for the separate debug
1706 info file in a set of known locations. The exact set of these
1707 locations varies depending upon the distribution being used, but it
1712 @item * The same directory as the executable.
1714 @item * A sub-directory of the directory containing the executable
1717 @item * A global debug directory such as /usr/lib/debug.
1720 As long as the debug info file has been installed into one of these
1721 locations before the debugger is run everything should work
1724 @item --keep-file-symbols
1725 When stripping a file, perhaps with @option{--strip-debug} or
1726 @option{--strip-unneeded}, retain any symbols specifying source file names,
1727 which would otherwise get stripped.
1729 @item --only-keep-debug
1730 Strip a file, removing contents of any sections that would not be
1731 stripped by @option{--strip-debug} and leaving the debugging sections
1732 intact. In ELF files, this preserves all note sections in the output.
1734 The intention is that this option will be used in conjunction with
1735 @option{--add-gnu-debuglink} to create a two part executable. One a
1736 stripped binary which will occupy less space in RAM and in a
1737 distribution and the second a debugging information file which is only
1738 needed if debugging abilities are required. The suggested procedure
1739 to create these files is as follows:
1742 @item Link the executable as normal. Assuming that is is called
1744 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1745 create a file containing the debugging info.
1746 @item Run @code{objcopy --strip-debug foo} to create a
1747 stripped executable.
1748 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1749 to add a link to the debugging info into the stripped executable.
1752 Note---the choice of @code{.dbg} as an extension for the debug info
1753 file is arbitrary. Also the @code{--only-keep-debug} step is
1754 optional. You could instead do this:
1757 @item Link the executable as normal.
1758 @item Copy @code{foo} to @code{foo.full}
1759 @item Run @code{objcopy --strip-debug foo}
1760 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1763 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1764 full executable. It does not have to be a file created by the
1765 @option{--only-keep-debug} switch.
1767 Note---this switch is only intended for use on fully linked files. It
1768 does not make sense to use it on object files where the debugging
1769 information may be incomplete. Besides the gnu_debuglink feature
1770 currently only supports the presence of one filename containing
1771 debugging information, not multiple filenames on a one-per-object-file
1775 Remove the contents of all DWARF .dwo sections, leaving the
1776 remaining debugging sections and all symbols intact.
1777 This option is intended for use by the compiler as part of
1778 the @option{-gsplit-dwarf} option, which splits debug information
1779 between the .o file and a separate .dwo file. The compiler
1780 generates all debug information in the same file, then uses
1781 the @option{--extract-dwo} option to copy the .dwo sections to
1782 the .dwo file, then the @option{--strip-dwo} option to remove
1783 those sections from the original .o file.
1786 Extract the contents of all DWARF .dwo sections. See the
1787 @option{--strip-dwo} option for more information.
1789 @item --file-alignment @var{num}
1790 Specify the file alignment. Sections in the file will always begin at
1791 file offsets which are multiples of this number. This defaults to
1793 [This option is specific to PE targets.]
1795 @item --heap @var{reserve}
1796 @itemx --heap @var{reserve},@var{commit}
1797 Specify the number of bytes of memory to reserve (and optionally commit)
1798 to be used as heap for this program.
1799 [This option is specific to PE targets.]
1801 @item --image-base @var{value}
1802 Use @var{value} as the base address of your program or dll. This is
1803 the lowest memory location that will be used when your program or dll
1804 is loaded. To reduce the need to relocate and improve performance of
1805 your dlls, each should have a unique base address and not overlap any
1806 other dlls. The default is 0x400000 for executables, and 0x10000000
1808 [This option is specific to PE targets.]
1810 @item --section-alignment @var{num}
1811 Sets the section alignment. Sections in memory will always begin at
1812 addresses which are a multiple of this number. Defaults to 0x1000.
1813 [This option is specific to PE targets.]
1815 @item --stack @var{reserve}
1816 @itemx --stack @var{reserve},@var{commit}
1817 Specify the number of bytes of memory to reserve (and optionally commit)
1818 to be used as stack for this program.
1819 [This option is specific to PE targets.]
1821 @item --subsystem @var{which}
1822 @itemx --subsystem @var{which}:@var{major}
1823 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1824 Specifies the subsystem under which your program will execute. The
1825 legal values for @var{which} are @code{native}, @code{windows},
1826 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1827 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1828 the subsystem version also. Numeric values are also accepted for
1830 [This option is specific to PE targets.]
1832 @item --extract-symbol
1833 Keep the file's section flags and symbols but remove all section data.
1834 Specifically, the option:
1837 @item removes the contents of all sections;
1838 @item sets the size of every section to zero; and
1839 @item sets the file's start address to zero.
1842 This option is used to build a @file{.sym} file for a VxWorks kernel.
1843 It can also be a useful way of reducing the size of a @option{--just-symbols}
1846 @item --compress-debug-sections
1847 Compress DWARF debug sections using zlib.
1849 @item --decompress-debug-sections
1850 Decompress DWARF debug sections using zlib.
1854 Show the version number of @command{objcopy}.
1858 Verbose output: list all object files modified. In the case of
1859 archives, @samp{objcopy -V} lists all members of the archive.
1862 Show a summary of the options to @command{objcopy}.
1865 Display a list showing all architectures and object formats available.
1871 @c man begin SEEALSO objcopy
1872 ld(1), objdump(1), and the Info entries for @file{binutils}.
1879 @cindex object file information
1882 @c man title objdump display information from object files.
1885 @c man begin SYNOPSIS objdump
1886 objdump [@option{-a}|@option{--archive-headers}]
1887 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1888 [@option{-C}|@option{--demangle}[=@var{style}] ]
1889 [@option{-d}|@option{--disassemble}]
1890 [@option{-D}|@option{--disassemble-all}]
1891 [@option{-z}|@option{--disassemble-zeroes}]
1892 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1893 [@option{-f}|@option{--file-headers}]
1894 [@option{-F}|@option{--file-offsets}]
1895 [@option{--file-start-context}]
1896 [@option{-g}|@option{--debugging}]
1897 [@option{-e}|@option{--debugging-tags}]
1898 [@option{-h}|@option{--section-headers}|@option{--headers}]
1899 [@option{-i}|@option{--info}]
1900 [@option{-j} @var{section}|@option{--section=}@var{section}]
1901 [@option{-l}|@option{--line-numbers}]
1902 [@option{-S}|@option{--source}]
1903 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1904 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1905 [@option{-p}|@option{--private-headers}]
1906 [@option{-P} @var{options}|@option{--private=}@var{options}]
1907 [@option{-r}|@option{--reloc}]
1908 [@option{-R}|@option{--dynamic-reloc}]
1909 [@option{-s}|@option{--full-contents}]
1910 [@option{-W[lLiaprmfFsoRt]}|
1911 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames]
1912 [=aranges,=macro,=frames,=frames-interp,=str,=loc]
1913 [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
1914 [=trace_aranges,=gdb_index]
1915 [@option{-G}|@option{--stabs}]
1916 [@option{-t}|@option{--syms}]
1917 [@option{-T}|@option{--dynamic-syms}]
1918 [@option{-x}|@option{--all-headers}]
1919 [@option{-w}|@option{--wide}]
1920 [@option{--start-address=}@var{address}]
1921 [@option{--stop-address=}@var{address}]
1922 [@option{--prefix-addresses}]
1923 [@option{--[no-]show-raw-insn}]
1924 [@option{--adjust-vma=}@var{offset}]
1925 [@option{--special-syms}]
1926 [@option{--prefix=}@var{prefix}]
1927 [@option{--prefix-strip=}@var{level}]
1928 [@option{--insn-width=}@var{width}]
1929 [@option{-V}|@option{--version}]
1930 [@option{-H}|@option{--help}]
1931 @var{objfile}@dots{}
1935 @c man begin DESCRIPTION objdump
1937 @command{objdump} displays information about one or more object files.
1938 The options control what particular information to display. This
1939 information is mostly useful to programmers who are working on the
1940 compilation tools, as opposed to programmers who just want their
1941 program to compile and work.
1943 @var{objfile}@dots{} are the object files to be examined. When you
1944 specify archives, @command{objdump} shows information on each of the member
1949 @c man begin OPTIONS objdump
1951 The long and short forms of options, shown here as alternatives, are
1952 equivalent. At least one option from the list
1953 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1957 @itemx --archive-header
1958 @cindex archive headers
1959 If any of the @var{objfile} files are archives, display the archive
1960 header information (in a format similar to @samp{ls -l}). Besides the
1961 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1962 the object file format of each archive member.
1964 @item --adjust-vma=@var{offset}
1965 @cindex section addresses in objdump
1966 @cindex VMA in objdump
1967 When dumping information, first add @var{offset} to all the section
1968 addresses. This is useful if the section addresses do not correspond to
1969 the symbol table, which can happen when putting sections at particular
1970 addresses when using a format which can not represent section addresses,
1973 @item -b @var{bfdname}
1974 @itemx --target=@var{bfdname}
1975 @cindex object code format
1976 Specify that the object-code format for the object files is
1977 @var{bfdname}. This option may not be necessary; @var{objdump} can
1978 automatically recognize many formats.
1982 objdump -b oasys -m vax -h fu.o
1985 displays summary information from the section headers (@option{-h}) of
1986 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1987 file in the format produced by Oasys compilers. You can list the
1988 formats available with the @option{-i} option.
1989 @xref{Target Selection}, for more information.
1992 @itemx --demangle[=@var{style}]
1993 @cindex demangling in objdump
1994 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1995 Besides removing any initial underscore prepended by the system, this
1996 makes C++ function names readable. Different compilers have different
1997 mangling styles. The optional demangling style argument can be used to
1998 choose an appropriate demangling style for your compiler. @xref{c++filt},
1999 for more information on demangling.
2003 Display debugging information. This attempts to parse STABS and IEEE
2004 debugging format information stored in the file and print it out using
2005 a C like syntax. If neither of these formats are found this option
2006 falls back on the @option{-W} option to print any DWARF information in
2010 @itemx --debugging-tags
2011 Like @option{-g}, but the information is generated in a format compatible
2015 @itemx --disassemble
2016 @cindex disassembling object code
2017 @cindex machine instructions
2018 Display the assembler mnemonics for the machine instructions from
2019 @var{objfile}. This option only disassembles those sections which are
2020 expected to contain instructions.
2023 @itemx --disassemble-all
2024 Like @option{-d}, but disassemble the contents of all sections, not just
2025 those expected to contain instructions.
2027 If the target is an ARM architecture this switch also has the effect
2028 of forcing the disassembler to decode pieces of data found in code
2029 sections as if they were instructions.
2031 @item --prefix-addresses
2032 When disassembling, print the complete address on each line. This is
2033 the older disassembly format.
2037 @itemx --endian=@{big|little@}
2039 @cindex disassembly endianness
2040 Specify the endianness of the object files. This only affects
2041 disassembly. This can be useful when disassembling a file format which
2042 does not describe endianness information, such as S-records.
2045 @itemx --file-headers
2046 @cindex object file header
2047 Display summary information from the overall header of
2048 each of the @var{objfile} files.
2051 @itemx --file-offsets
2052 @cindex object file offsets
2053 When disassembling sections, whenever a symbol is displayed, also
2054 display the file offset of the region of data that is about to be
2055 dumped. If zeroes are being skipped, then when disassembly resumes,
2056 tell the user how many zeroes were skipped and the file offset of the
2057 location from where the disassembly resumes. When dumping sections,
2058 display the file offset of the location from where the dump starts.
2060 @item --file-start-context
2061 @cindex source code context
2062 Specify that when displaying interlisted source code/disassembly
2063 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2064 context to the start of the file.
2067 @itemx --section-headers
2069 @cindex section headers
2070 Display summary information from the section headers of the
2073 File segments may be relocated to nonstandard addresses, for example by
2074 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2075 @command{ld}. However, some object file formats, such as a.out, do not
2076 store the starting address of the file segments. In those situations,
2077 although @command{ld} relocates the sections correctly, using @samp{objdump
2078 -h} to list the file section headers cannot show the correct addresses.
2079 Instead, it shows the usual addresses, which are implicit for the
2084 Print a summary of the options to @command{objdump} and exit.
2088 @cindex architectures available
2089 @cindex object formats available
2090 Display a list showing all architectures and object formats available
2091 for specification with @option{-b} or @option{-m}.
2094 @itemx --section=@var{name}
2095 @cindex section information
2096 Display information only for section @var{name}.
2099 @itemx --line-numbers
2100 @cindex source filenames for object files
2101 Label the display (using debugging information) with the filename and
2102 source line numbers corresponding to the object code or relocs shown.
2103 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2105 @item -m @var{machine}
2106 @itemx --architecture=@var{machine}
2107 @cindex architecture
2108 @cindex disassembly architecture
2109 Specify the architecture to use when disassembling object files. This
2110 can be useful when disassembling object files which do not describe
2111 architecture information, such as S-records. You can list the available
2112 architectures with the @option{-i} option.
2114 If the target is an ARM architecture then this switch has an
2115 additional effect. It restricts the disassembly to only those
2116 instructions supported by the architecture specified by @var{machine}.
2117 If it is necessary to use this switch because the input file does not
2118 contain any architecture information, but it is also desired to
2119 disassemble all the instructions use @option{-marm}.
2121 @item -M @var{options}
2122 @itemx --disassembler-options=@var{options}
2123 Pass target specific information to the disassembler. Only supported on
2124 some targets. If it is necessary to specify more than one
2125 disassembler option then multiple @option{-M} options can be used or
2126 can be placed together into a comma separated list.
2128 If the target is an ARM architecture then this switch can be used to
2129 select which register name set is used during disassembler. Specifying
2130 @option{-M reg-names-std} (the default) will select the register names as
2131 used in ARM's instruction set documentation, but with register 13 called
2132 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2133 @option{-M reg-names-apcs} will select the name set used by the ARM
2134 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2135 just use @samp{r} followed by the register number.
2137 There are also two variants on the APCS register naming scheme enabled
2138 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2139 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2140 with the normal register names or the special register names).
2142 This option can also be used for ARM architectures to force the
2143 disassembler to interpret all instructions as Thumb instructions by
2144 using the switch @option{--disassembler-options=force-thumb}. This can be
2145 useful when attempting to disassemble thumb code produced by other
2148 For the x86, some of the options duplicate functions of the @option{-m}
2149 switch, but allow finer grained control. Multiple selections from the
2150 following may be specified as a comma separated string.
2155 Select disassembly for the given architecture.
2159 Select between intel syntax mode and AT&T syntax mode.
2161 @item intel-mnemonic
2163 Select between intel mnemonic mode and AT&T mnemonic mode.
2164 Note: @code{intel-mnemonic} implies @code{intel} and
2165 @code{att-mnemonic} implies @code{att}.
2172 Specify the default address size and operand size. These four options
2173 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2174 appear later in the option string.
2177 When in AT&T mode, instructs the disassembler to print a mnemonic
2178 suffix even when the suffix could be inferred by the operands.
2181 For PowerPC, @option{booke} controls the disassembly of BookE
2182 instructions. @option{32} and @option{64} select PowerPC and
2183 PowerPC64 disassembly, respectively. @option{e300} selects
2184 disassembly for the e300 family. @option{440} selects disassembly for
2185 the PowerPC 440. @option{ppcps} selects disassembly for the paired
2186 single instructions of the PPC750CL.
2188 For MIPS, this option controls the printing of instruction mnemonic
2189 names and register names in disassembled instructions. Multiple
2190 selections from the following may be specified as a comma separated
2191 string, and invalid options are ignored:
2195 Print the 'raw' instruction mnemonic instead of some pseudo
2196 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2197 'sll' instead of 'nop', etc.
2200 Disassemble MSA instructions.
2203 Disassemble the virtualization ASE instructions.
2206 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2208 @item gpr-names=@var{ABI}
2209 Print GPR (general-purpose register) names as appropriate
2210 for the specified ABI. By default, GPR names are selected according to
2211 the ABI of the binary being disassembled.
2213 @item fpr-names=@var{ABI}
2214 Print FPR (floating-point register) names as
2215 appropriate for the specified ABI. By default, FPR numbers are printed
2218 @item cp0-names=@var{ARCH}
2219 Print CP0 (system control coprocessor; coprocessor 0) register names
2220 as appropriate for the CPU or architecture specified by
2221 @var{ARCH}. By default, CP0 register names are selected according to
2222 the architecture and CPU of the binary being disassembled.
2224 @item hwr-names=@var{ARCH}
2225 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2226 as appropriate for the CPU or architecture specified by
2227 @var{ARCH}. By default, HWR names are selected according to
2228 the architecture and CPU of the binary being disassembled.
2230 @item reg-names=@var{ABI}
2231 Print GPR and FPR names as appropriate for the selected ABI.
2233 @item reg-names=@var{ARCH}
2234 Print CPU-specific register names (CP0 register and HWR names)
2235 as appropriate for the selected CPU or architecture.
2238 For any of the options listed above, @var{ABI} or
2239 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2240 rather than names, for the selected types of registers.
2241 You can list the available values of @var{ABI} and @var{ARCH} using
2242 the @option{--help} option.
2244 For VAX, you can specify function entry addresses with @option{-M
2245 entry:0xf00ba}. You can use this multiple times to properly
2246 disassemble VAX binary files that don't contain symbol tables (like
2247 ROM dumps). In these cases, the function entry mask would otherwise
2248 be decoded as VAX instructions, which would probably lead the rest
2249 of the function being wrongly disassembled.
2252 @itemx --private-headers
2253 Print information that is specific to the object file format. The exact
2254 information printed depends upon the object file format. For some
2255 object file formats, no additional information is printed.
2257 @item -P @var{options}
2258 @itemx --private=@var{options}
2259 Print information that is specific to the object file format. The
2260 argument @var{options} is a comma separated list that depends on the
2261 format (the lists of options is displayed with the help).
2263 For XCOFF, the available options are:
2279 Not all object formats support this option. In particular the ELF
2280 format does not use it.
2284 @cindex relocation entries, in object file
2285 Print the relocation entries of the file. If used with @option{-d} or
2286 @option{-D}, the relocations are printed interspersed with the
2290 @itemx --dynamic-reloc
2291 @cindex dynamic relocation entries, in object file
2292 Print the dynamic relocation entries of the file. This is only
2293 meaningful for dynamic objects, such as certain types of shared
2294 libraries. As for @option{-r}, if used with @option{-d} or
2295 @option{-D}, the relocations are printed interspersed with the
2299 @itemx --full-contents
2300 @cindex sections, full contents
2301 @cindex object file sections
2302 Display the full contents of any sections requested. By default all
2303 non-empty sections are displayed.
2307 @cindex source disassembly
2308 @cindex disassembly, with source
2309 Display source code intermixed with disassembly, if possible. Implies
2312 @item --prefix=@var{prefix}
2313 @cindex Add prefix to absolute paths
2314 Specify @var{prefix} to add to the absolute paths when used with
2317 @item --prefix-strip=@var{level}
2318 @cindex Strip absolute paths
2319 Indicate how many initial directory names to strip off the hardwired
2320 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2322 @item --show-raw-insn
2323 When disassembling instructions, print the instruction in hex as well as
2324 in symbolic form. This is the default except when
2325 @option{--prefix-addresses} is used.
2327 @item --no-show-raw-insn
2328 When disassembling instructions, do not print the instruction bytes.
2329 This is the default when @option{--prefix-addresses} is used.
2331 @item --insn-width=@var{width}
2332 @cindex Instruction width
2333 Display @var{width} bytes on a single line when disassembling
2336 @item -W[lLiaprmfFsoRt]
2337 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
2338 @itemx --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
2339 @itemx --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2340 @itemx --dwarf[=trace_aranges,=gdb_index]
2342 @cindex debug symbols
2343 Displays the contents of the debug sections in the file, if any are
2344 present. If one of the optional letters or words follows the switch
2345 then only data found in those specific sections will be dumped.
2347 Note that there is no single letter option to display the content of
2348 trace sections or .gdb_index.
2350 Note: the output from the @option{=info} option can also be affected
2351 by the options @option{--dwarf-depth}, the @option{--dwarf-start} and
2352 the @option{--dwarf-check}.
2354 @item --dwarf-depth=@var{n}
2355 Limit the dump of the @code{.debug_info} section to @var{n} children.
2356 This is only useful with @option{--dwarf=info}. The default is
2357 to print all DIEs; the special value 0 for @var{n} will also have this
2360 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
2361 levels will not be printed. The range for @var{n} is zero-based.
2363 @item --dwarf-start=@var{n}
2364 Print only DIEs beginning with the DIE numbered @var{n}. This is only
2365 useful with @option{--dwarf=info}.
2367 If specified, this option will suppress printing of any header
2368 information and all DIEs before the DIE numbered @var{n}. Only
2369 siblings and children of the specified DIE will be printed.
2371 This can be used in conjunction with @option{--dwarf-depth}.
2374 Enable additional checks for consistency of Dwarf information.
2380 @cindex debug symbols
2381 @cindex ELF object file format
2382 Display the full contents of any sections requested. Display the
2383 contents of the .stab and .stab.index and .stab.excl sections from an
2384 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2385 @code{.stab} debugging symbol-table entries are carried in an ELF
2386 section. In most other file formats, debugging symbol-table entries are
2387 interleaved with linkage symbols, and are visible in the @option{--syms}
2390 @item --start-address=@var{address}
2391 @cindex start-address
2392 Start displaying data at the specified address. This affects the output
2393 of the @option{-d}, @option{-r} and @option{-s} options.
2395 @item --stop-address=@var{address}
2396 @cindex stop-address
2397 Stop displaying data at the specified address. This affects the output
2398 of the @option{-d}, @option{-r} and @option{-s} options.
2402 @cindex symbol table entries, printing
2403 Print the symbol table entries of the file.
2404 This is similar to the information provided by the @samp{nm} program,
2405 although the display format is different. The format of the output
2406 depends upon the format of the file being dumped, but there are two main
2407 types. One looks like this:
2410 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2411 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2414 where the number inside the square brackets is the number of the entry
2415 in the symbol table, the @var{sec} number is the section number, the
2416 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2417 symbol's type, the @var{scl} number is the symbol's storage class and
2418 the @var{nx} value is the number of auxilary entries associated with
2419 the symbol. The last two fields are the symbol's value and its name.
2421 The other common output format, usually seen with ELF based files,
2425 00000000 l d .bss 00000000 .bss
2426 00000000 g .text 00000000 fred
2429 Here the first number is the symbol's value (sometimes refered to as
2430 its address). The next field is actually a set of characters and
2431 spaces indicating the flag bits that are set on the symbol. These
2432 characters are described below. Next is the section with which the
2433 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2434 not connected with any section), or @emph{*UND*} if the section is
2435 referenced in the file being dumped, but not defined there.
2437 After the section name comes another field, a number, which for common
2438 symbols is the alignment and for other symbol is the size. Finally
2439 the symbol's name is displayed.
2441 The flag characters are divided into 7 groups as follows:
2447 The symbol is a local (l), global (g), unique global (u), neither
2448 global nor local (a space) or both global and local (!). A
2449 symbol can be neither local or global for a variety of reasons, e.g.,
2450 because it is used for debugging, but it is probably an indication of
2451 a bug if it is ever both local and global. Unique global symbols are
2452 a GNU extension to the standard set of ELF symbol bindings. For such
2453 a symbol the dynamic linker will make sure that in the entire process
2454 there is just one symbol with this name and type in use.
2457 The symbol is weak (w) or strong (a space).
2460 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2463 The symbol is a warning (W) or a normal symbol (a space). A warning
2464 symbol's name is a message to be displayed if the symbol following the
2465 warning symbol is ever referenced.
2469 The symbol is an indirect reference to another symbol (I), a function
2470 to be evaluated during reloc processing (i) or a normal symbol (a
2475 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2476 normal symbol (a space).
2481 The symbol is the name of a function (F) or a file (f) or an object
2482 (O) or just a normal symbol (a space).
2486 @itemx --dynamic-syms
2487 @cindex dynamic symbol table entries, printing
2488 Print the dynamic symbol table entries of the file. This is only
2489 meaningful for dynamic objects, such as certain types of shared
2490 libraries. This is similar to the information provided by the @samp{nm}
2491 program when given the @option{-D} (@option{--dynamic}) option.
2493 @item --special-syms
2494 When displaying symbols include those which the target considers to be
2495 special in some way and which would not normally be of interest to the
2500 Print the version number of @command{objdump} and exit.
2503 @itemx --all-headers
2504 @cindex all header information, object file
2505 @cindex header information, all
2506 Display all available header information, including the symbol table and
2507 relocation entries. Using @option{-x} is equivalent to specifying all of
2508 @option{-a -f -h -p -r -t}.
2512 @cindex wide output, printing
2513 Format some lines for output devices that have more than 80 columns.
2514 Also do not truncate symbol names when they are displayed.
2517 @itemx --disassemble-zeroes
2518 Normally the disassembly output will skip blocks of zeroes. This
2519 option directs the disassembler to disassemble those blocks, just like
2526 @c man begin SEEALSO objdump
2527 nm(1), readelf(1), and the Info entries for @file{binutils}.
2535 @cindex archive contents
2536 @cindex symbol index
2538 @c man title ranlib generate index to archive.
2541 @c man begin SYNOPSIS ranlib
2542 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2546 @c man begin DESCRIPTION ranlib
2548 @command{ranlib} generates an index to the contents of an archive and
2549 stores it in the archive. The index lists each symbol defined by a
2550 member of an archive that is a relocatable object file.
2552 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2554 An archive with such an index speeds up linking to the library and
2555 allows routines in the library to call each other without regard to
2556 their placement in the archive.
2558 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2559 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2564 @c man begin OPTIONS ranlib
2570 Show usage information for @command{ranlib}.
2575 Show the version number of @command{ranlib}.
2578 @cindex deterministic archives
2579 @kindex --enable-deterministic-archives
2580 Operate in @emph{deterministic} mode. The symbol map archive member's
2581 header will show zero for the UID, GID, and timestamp. When this
2582 option is used, multiple runs will produce identical output files.
2584 If @file{binutils} was configured with
2585 @option{--enable-deterministic-archives}, then this mode is on by
2586 default. It can be disabled with the @samp{-U} option, described
2590 Update the timestamp of the symbol map of an archive.
2593 @cindex deterministic archives
2594 @kindex --enable-deterministic-archives
2595 Do @emph{not} operate in @emph{deterministic} mode. This is the
2596 inverse of the @samp{-D} option, above: the archive index will get
2597 actual UID, GID, timestamp, and file mode values.
2599 If @file{binutils} was configured @emph{without}
2600 @option{--enable-deterministic-archives}, then this mode is on by
2608 @c man begin SEEALSO ranlib
2609 ar(1), nm(1), and the Info entries for @file{binutils}.
2617 @cindex section sizes
2619 @c man title size list section sizes and total size.
2622 @c man begin SYNOPSIS size
2623 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2625 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2627 [@option{-t}|@option{--totals}]
2628 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2629 [@var{objfile}@dots{}]
2633 @c man begin DESCRIPTION size
2635 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2636 size---for each of the object or archive files @var{objfile} in its
2637 argument list. By default, one line of output is generated for each
2638 object file or each module in an archive.
2640 @var{objfile}@dots{} are the object files to be examined.
2641 If none are specified, the file @code{a.out} will be used.
2645 @c man begin OPTIONS size
2647 The command line options have the following meanings:
2652 @itemx --format=@var{compatibility}
2653 @cindex @command{size} display format
2654 Using one of these options, you can choose whether the output from @sc{gnu}
2655 @command{size} resembles output from System V @command{size} (using @option{-A},
2656 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2657 @option{--format=berkeley}). The default is the one-line format similar to
2659 @c Bonus for doc-source readers: you can also say --format=strange (or
2660 @c anything else that starts with 's') for sysv, and --format=boring (or
2661 @c anything else that starts with 'b') for Berkeley.
2663 Here is an example of the Berkeley (default) format of output from
2666 $ size --format=Berkeley ranlib size
2667 text data bss dec hex filename
2668 294880 81920 11592 388392 5ed28 ranlib
2669 294880 81920 11888 388688 5ee50 size
2673 This is the same data, but displayed closer to System V conventions:
2676 $ size --format=SysV ranlib size
2694 Show a summary of acceptable arguments and options.
2699 @itemx --radix=@var{number}
2700 @cindex @command{size} number format
2701 @cindex radix for section sizes
2702 Using one of these options, you can control whether the size of each
2703 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2704 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2705 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2706 values (8, 10, 16) are supported. The total size is always given in two
2707 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2708 octal and hexadecimal if you're using @option{-o}.
2711 Print total size of common symbols in each file. When using Berkeley
2712 format these are included in the bss size.
2716 Show totals of all objects listed (Berkeley format listing mode only).
2718 @item --target=@var{bfdname}
2719 @cindex object code format
2720 Specify that the object-code format for @var{objfile} is
2721 @var{bfdname}. This option may not be necessary; @command{size} can
2722 automatically recognize many formats.
2723 @xref{Target Selection}, for more information.
2727 Display the version number of @command{size}.
2733 @c man begin SEEALSO size
2734 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2741 @cindex listings strings
2742 @cindex printing strings
2743 @cindex strings, printing
2745 @c man title strings print the strings of printable characters in files.
2748 @c man begin SYNOPSIS strings
2749 strings [@option{-afovV}] [@option{-}@var{min-len}]
2750 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2751 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2752 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2753 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2754 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2755 [@option{-w}] [@option{--include-all-whitespace}]
2756 [@option{--help}] [@option{--version}] @var{file}@dots{}
2760 @c man begin DESCRIPTION strings
2762 For each @var{file} given, @sc{gnu} @command{strings} prints the
2763 printable character sequences that are at least 4 characters long (or
2764 the number given with the options below) and are followed by an
2765 unprintable character.
2767 Depending upon how the strings program was configured it will default
2768 to either displaying all the printable sequences that it can find in
2769 each file, or only those sequences that are in loadable, initialized
2770 data sections. If the file type in unrecognizable, or if strings is
2771 reading from stdin then it will always display all of the printable
2772 sequences that it can find.
2774 For backwards compatibility any file that occurs after a command line
2775 option of just @option{-} will also be scanned in full, regardless of
2776 the presence of any @option{-d} option.
2778 @command{strings} is mainly useful for determining the contents of
2783 @c man begin OPTIONS strings
2789 Scan the whole file, regardless of what sections it contains or
2790 whether those sections are loaded or initialized. Normally this is
2791 the default behaviour, but strings can be configured so that the
2792 @option{-d} is the default instead.
2794 The @option{-} option is position dependent and forces strings to
2795 perform full scans of any file that is mentioned after the @option{-}
2796 on the command line, even if the @option{-d} option has been
2801 Only print strings from initialized, loaded data sections in the
2802 file. This may reduce the amount of garbage in the output, but it
2803 also exposes the strings program to any security flaws that may be
2804 present in the BFD library used to scan and load sections. Strings
2805 can be configured so that this option is the default behaviour. In
2806 such cases the @option{-a} option can be used to avoid using the BFD
2807 library and instead just print all of the strings found in the file.
2810 @itemx --print-file-name
2811 Print the name of the file before each string.
2814 Print a summary of the program usage on the standard output and exit.
2816 @item -@var{min-len}
2817 @itemx -n @var{min-len}
2818 @itemx --bytes=@var{min-len}
2819 Print sequences of characters that are at least @var{min-len} characters
2820 long, instead of the default 4.
2823 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2824 act like @samp{-t d} instead. Since we can not be compatible with both
2825 ways, we simply chose one.
2827 @item -t @var{radix}
2828 @itemx --radix=@var{radix}
2829 Print the offset within the file before each string. The single
2830 character argument specifies the radix of the offset---@samp{o} for
2831 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2833 @item -e @var{encoding}
2834 @itemx --encoding=@var{encoding}
2835 Select the character encoding of the strings that are to be found.
2836 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2837 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2838 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2839 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2840 littleendian. Useful for finding wide character strings. (@samp{l}
2841 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
2843 @item -T @var{bfdname}
2844 @itemx --target=@var{bfdname}
2845 @cindex object code format
2846 Specify an object code format other than your system's default format.
2847 @xref{Target Selection}, for more information.
2852 Print the program version number on the standard output and exit.
2855 @itemx --include-all-whitespace
2856 By default tab and space characters are included in the strings that
2857 are displayed, but other whitespace characters, such a newlines and
2858 carriage returns, are not. The @option{-w} option changes this so
2859 that all whitespace characters are considered to be part of a string.
2865 @c man begin SEEALSO strings
2866 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2867 and the Info entries for @file{binutils}.
2875 @cindex removing symbols
2876 @cindex discarding symbols
2877 @cindex symbols, discarding
2879 @c man title strip Discard symbols from object files.
2882 @c man begin SYNOPSIS strip
2883 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2884 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2885 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2886 [@option{-s}|@option{--strip-all}]
2887 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2888 [@option{--strip-dwo}]
2889 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2890 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2891 [@option{-w}|@option{--wildcard}]
2892 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2893 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2894 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2895 [@option{-D}|@option{--enable-deterministic-archives}]
2896 [@option{-U}|@option{--disable-deterministic-archives}]
2897 [@option{--keep-file-symbols}]
2898 [@option{--only-keep-debug}]
2899 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2900 [@option{--help}] [@option{--info}]
2901 @var{objfile}@dots{}
2905 @c man begin DESCRIPTION strip
2907 @sc{gnu} @command{strip} discards all symbols from object files
2908 @var{objfile}. The list of object files may include archives.
2909 At least one object file must be given.
2911 @command{strip} modifies the files named in its argument,
2912 rather than writing modified copies under different names.
2916 @c man begin OPTIONS strip
2919 @item -F @var{bfdname}
2920 @itemx --target=@var{bfdname}
2921 Treat the original @var{objfile} as a file with the object
2922 code format @var{bfdname}, and rewrite it in the same format.
2923 @xref{Target Selection}, for more information.
2926 Show a summary of the options to @command{strip} and exit.
2929 Display a list showing all architectures and object formats available.
2931 @item -I @var{bfdname}
2932 @itemx --input-target=@var{bfdname}
2933 Treat the original @var{objfile} as a file with the object
2934 code format @var{bfdname}.
2935 @xref{Target Selection}, for more information.
2937 @item -O @var{bfdname}
2938 @itemx --output-target=@var{bfdname}
2939 Replace @var{objfile} with a file in the output format @var{bfdname}.
2940 @xref{Target Selection}, for more information.
2942 @item -R @var{sectionname}
2943 @itemx --remove-section=@var{sectionname}
2944 Remove any section named @var{sectionname} from the output file, in
2945 addition to whatever sections would otherwise be removed. This
2946 option may be given more than once. Note that using this option
2947 inappropriately may make the output file unusable. The wildcard
2948 character @samp{*} may be given at the end of @var{sectionname}. If
2949 so, then any section starting with @var{sectionname} will be removed.
2958 @itemx --strip-debug
2959 Remove debugging symbols only.
2962 Remove the contents of all DWARF .dwo sections, leaving the
2963 remaining debugging sections and all symbols intact.
2964 See the description of this option in the @command{objcopy} section
2965 for more information.
2967 @item --strip-unneeded
2968 Remove all symbols that are not needed for relocation processing.
2970 @item -K @var{symbolname}
2971 @itemx --keep-symbol=@var{symbolname}
2972 When stripping symbols, keep symbol @var{symbolname} even if it would
2973 normally be stripped. This option may be given more than once.
2975 @item -N @var{symbolname}
2976 @itemx --strip-symbol=@var{symbolname}
2977 Remove symbol @var{symbolname} from the source file. This option may be
2978 given more than once, and may be combined with strip options other than
2982 Put the stripped output in @var{file}, rather than replacing the
2983 existing file. When this argument is used, only one @var{objfile}
2984 argument may be specified.
2987 @itemx --preserve-dates
2988 Preserve the access and modification dates of the file.
2991 @itemx --enable-deterministic-archives
2992 @cindex deterministic archives
2993 @kindex --enable-deterministic-archives
2994 Operate in @emph{deterministic} mode. When copying archive members
2995 and writing the archive index, use zero for UIDs, GIDs, timestamps,
2996 and use consistent file modes for all files.
2998 If @file{binutils} was configured with
2999 @option{--enable-deterministic-archives}, then this mode is on by default.
3000 It can be disabled with the @samp{-U} option, below.
3003 @itemx --disable-deterministic-archives
3004 @cindex deterministic archives
3005 @kindex --enable-deterministic-archives
3006 Do @emph{not} operate in @emph{deterministic} mode. This is the
3007 inverse of the @option{-D} option, above: when copying archive members
3008 and writing the archive index, use their actual UID, GID, timestamp,
3009 and file mode values.
3011 This is the default unless @file{binutils} was configured with
3012 @option{--enable-deterministic-archives}.
3016 Permit regular expressions in @var{symbolname}s used in other command
3017 line options. The question mark (?), asterisk (*), backslash (\) and
3018 square brackets ([]) operators can be used anywhere in the symbol
3019 name. If the first character of the symbol name is the exclamation
3020 point (!) then the sense of the switch is reversed for that symbol.
3027 would cause strip to only keep symbols that start with the letters
3028 ``fo'', but to discard the symbol ``foo''.
3031 @itemx --discard-all
3032 Remove non-global symbols.
3035 @itemx --discard-locals
3036 Remove compiler-generated local symbols.
3037 (These usually start with @samp{L} or @samp{.}.)
3039 @item --keep-file-symbols
3040 When stripping a file, perhaps with @option{--strip-debug} or
3041 @option{--strip-unneeded}, retain any symbols specifying source file names,
3042 which would otherwise get stripped.
3044 @item --only-keep-debug
3045 Strip a file, removing contents of any sections that would not be
3046 stripped by @option{--strip-debug} and leaving the debugging sections
3047 intact. In ELF files, this preserves all note sections in the output.
3049 The intention is that this option will be used in conjunction with
3050 @option{--add-gnu-debuglink} to create a two part executable. One a
3051 stripped binary which will occupy less space in RAM and in a
3052 distribution and the second a debugging information file which is only
3053 needed if debugging abilities are required. The suggested procedure
3054 to create these files is as follows:
3057 @item Link the executable as normal. Assuming that is is called
3059 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3060 create a file containing the debugging info.
3061 @item Run @code{objcopy --strip-debug foo} to create a
3062 stripped executable.
3063 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3064 to add a link to the debugging info into the stripped executable.
3067 Note---the choice of @code{.dbg} as an extension for the debug info
3068 file is arbitrary. Also the @code{--only-keep-debug} step is
3069 optional. You could instead do this:
3072 @item Link the executable as normal.
3073 @item Copy @code{foo} to @code{foo.full}
3074 @item Run @code{strip --strip-debug foo}
3075 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3078 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3079 full executable. It does not have to be a file created by the
3080 @option{--only-keep-debug} switch.
3082 Note---this switch is only intended for use on fully linked files. It
3083 does not make sense to use it on object files where the debugging
3084 information may be incomplete. Besides the gnu_debuglink feature
3085 currently only supports the presence of one filename containing
3086 debugging information, not multiple filenames on a one-per-object-file
3091 Show the version number for @command{strip}.
3095 Verbose output: list all object files modified. In the case of
3096 archives, @samp{strip -v} lists all members of the archive.
3102 @c man begin SEEALSO strip
3103 the Info entries for @file{binutils}.
3107 @node c++filt, addr2line, strip, Top
3111 @cindex demangling C++ symbols
3113 @c man title cxxfilt Demangle C++ and Java symbols.
3116 @c man begin SYNOPSIS cxxfilt
3117 c++filt [@option{-_}|@option{--strip-underscore}]
3118 [@option{-n}|@option{--no-strip-underscore}]
3119 [@option{-p}|@option{--no-params}]
3120 [@option{-t}|@option{--types}]
3121 [@option{-i}|@option{--no-verbose}]
3122 [@option{-s} @var{format}|@option{--format=}@var{format}]
3123 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3127 @c man begin DESCRIPTION cxxfilt
3130 The C++ and Java languages provide function overloading, which means
3131 that you can write many functions with the same name, providing that
3132 each function takes parameters of different types. In order to be
3133 able to distinguish these similarly named functions C++ and Java
3134 encode them into a low-level assembler name which uniquely identifies
3135 each different version. This process is known as @dfn{mangling}. The
3137 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3138 MS-DOS this program is named @command{CXXFILT}.}
3139 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3140 names into user-level names so that they can be read.
3142 Every alphanumeric word (consisting of letters, digits, underscores,
3143 dollars, or periods) seen in the input is a potential mangled name.
3144 If the name decodes into a C++ name, the C++ name replaces the
3145 low-level name in the output, otherwise the original word is output.
3146 In this way you can pass an entire assembler source file, containing
3147 mangled names, through @command{c++filt} and see the same source file
3148 containing demangled names.
3150 You can also use @command{c++filt} to decipher individual symbols by
3151 passing them on the command line:
3154 c++filt @var{symbol}
3157 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3158 names from the standard input instead. All the results are printed on
3159 the standard output. The difference between reading names from the
3160 command line versus reading names from the standard input is that
3161 command line arguments are expected to be just mangled names and no
3162 checking is performed to separate them from surrounding text. Thus
3169 will work and demangle the name to ``f()'' whereas:
3175 will not work. (Note the extra comma at the end of the mangled
3176 name which makes it invalid). This command however will work:
3179 echo _Z1fv, | c++filt -n
3182 and will display ``f(),'', i.e., the demangled name followed by a
3183 trailing comma. This behaviour is because when the names are read
3184 from the standard input it is expected that they might be part of an
3185 assembler source file where there might be extra, extraneous
3186 characters trailing after a mangled name. For example:
3189 .type _Z1fv, @@function
3194 @c man begin OPTIONS cxxfilt
3198 @itemx --strip-underscore
3199 On some systems, both the C and C++ compilers put an underscore in front
3200 of every name. For example, the C name @code{foo} gets the low-level
3201 name @code{_foo}. This option removes the initial underscore. Whether
3202 @command{c++filt} removes the underscore by default is target dependent.
3205 @itemx --no-strip-underscore
3206 Do not remove the initial underscore.
3210 When demangling the name of a function, do not display the types of
3211 the function's parameters.
3215 Attempt to demangle types as well as function names. This is disabled
3216 by default since mangled types are normally only used internally in
3217 the compiler, and they can be confused with non-mangled names. For example,
3218 a function called ``a'' treated as a mangled type name would be
3219 demangled to ``signed char''.
3223 Do not include implementation details (if any) in the demangled
3226 @item -s @var{format}
3227 @itemx --format=@var{format}
3228 @command{c++filt} can decode various methods of mangling, used by
3229 different compilers. The argument to this option selects which
3234 Automatic selection based on executable (the default method)
3236 the one used by the @sc{gnu} C++ compiler (g++)
3238 the one used by the Lucid compiler (lcc)
3240 the one specified by the C++ Annotated Reference Manual
3242 the one used by the HP compiler (aCC)
3244 the one used by the EDG compiler
3246 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3248 the one used by the @sc{gnu} Java compiler (gcj)
3250 the one used by the @sc{gnu} Ada compiler (GNAT).
3254 Print a summary of the options to @command{c++filt} and exit.
3257 Print the version number of @command{c++filt} and exit.
3263 @c man begin SEEALSO cxxfilt
3264 the Info entries for @file{binutils}.
3269 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3270 user interface are subject to change in future releases. In particular,
3271 a command-line option may be required in the future to decode a name
3272 passed as an argument on the command line; in other words,
3275 c++filt @var{symbol}
3279 may in a future release become
3282 c++filt @var{option} @var{symbol}
3290 @cindex address to file name and line number
3292 @c man title addr2line convert addresses into file names and line numbers.
3295 @c man begin SYNOPSIS addr2line
3296 addr2line [@option{-a}|@option{--addresses}]
3297 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3298 [@option{-C}|@option{--demangle}[=@var{style}]]
3299 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3300 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3301 [@option{-i}|@option{--inlines}]
3302 [@option{-p}|@option{--pretty-print}]
3303 [@option{-j}|@option{--section=}@var{name}]
3304 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3309 @c man begin DESCRIPTION addr2line
3311 @command{addr2line} translates addresses into file names and line numbers.
3312 Given an address in an executable or an offset in a section of a relocatable
3313 object, it uses the debugging information to figure out which file name and
3314 line number are associated with it.
3316 The executable or relocatable object to use is specified with the @option{-e}
3317 option. The default is the file @file{a.out}. The section in the relocatable
3318 object to use is specified with the @option{-j} option.
3320 @command{addr2line} has two modes of operation.
3322 In the first, hexadecimal addresses are specified on the command line,
3323 and @command{addr2line} displays the file name and line number for each
3326 In the second, @command{addr2line} reads hexadecimal addresses from
3327 standard input, and prints the file name and line number for each
3328 address on standard output. In this mode, @command{addr2line} may be used
3329 in a pipe to convert dynamically chosen addresses.
3331 The format of the output is @samp{FILENAME:LINENO}. By default
3332 each input address generates one line of output.
3334 Two options can generate additional lines before each
3335 @samp{FILENAME:LINENO} line (in that order).
3337 If the @option{-a} option is used then a line with the input address
3340 If the @option{-f} option is used, then a line with the
3341 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3342 containing the address.
3344 One option can generate additional lines after the
3345 @samp{FILENAME:LINENO} line.
3347 If the @option{-i} option is used and the code at the given address is
3348 present there because of inlining by the compiler then additional
3349 lines are displayed afterwards. One or two extra lines (if the
3350 @option{-f} option is used) are displayed for each inlined function.
3352 Alternatively if the @option{-p} option is used then each input
3353 address generates a single, long, output line containing the address,
3354 the function name, the file name and the line number. If the
3355 @option{-i} option has also been used then any inlined functions will
3356 be displayed in the same manner, but on separate lines, and prefixed
3357 by the text @samp{(inlined by)}.
3359 If the file name or function name can not be determined,
3360 @command{addr2line} will print two question marks in their place. If the
3361 line number can not be determined, @command{addr2line} will print 0.
3365 @c man begin OPTIONS addr2line
3367 The long and short forms of options, shown here as alternatives, are
3373 Display the address before the function name, file and line number
3374 information. The address is printed with a @samp{0x} prefix to easily
3377 @item -b @var{bfdname}
3378 @itemx --target=@var{bfdname}
3379 @cindex object code format
3380 Specify that the object-code format for the object files is
3384 @itemx --demangle[=@var{style}]
3385 @cindex demangling in objdump
3386 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3387 Besides removing any initial underscore prepended by the system, this
3388 makes C++ function names readable. Different compilers have different
3389 mangling styles. The optional demangling style argument can be used to
3390 choose an appropriate demangling style for your compiler. @xref{c++filt},
3391 for more information on demangling.
3393 @item -e @var{filename}
3394 @itemx --exe=@var{filename}
3395 Specify the name of the executable for which addresses should be
3396 translated. The default file is @file{a.out}.
3400 Display function names as well as file and line number information.
3404 Display only the base of each file name.
3408 If the address belongs to a function that was inlined, the source
3409 information for all enclosing scopes back to the first non-inlined
3410 function will also be printed. For example, if @code{main} inlines
3411 @code{callee1} which inlines @code{callee2}, and address is from
3412 @code{callee2}, the source information for @code{callee1} and @code{main}
3413 will also be printed.
3417 Read offsets relative to the specified section instead of absolute addresses.
3420 @itemx --pretty-print
3421 Make the output more human friendly: each location are printed on one line.
3422 If option @option{-i} is specified, lines for all enclosing scopes are
3423 prefixed with @samp{(inlined by)}.
3429 @c man begin SEEALSO addr2line
3430 Info entries for @file{binutils}.
3437 @command{nlmconv} converts a relocatable object file into a NetWare
3441 @command{nlmconv} currently works with @samp{i386} object
3442 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3443 object files in @sc{elf}, or @code{a.out} format@footnote{
3444 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3445 format in the Binary File Descriptor library. It has only been tested
3446 with the above formats.}.
3450 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3451 utilities, since it is only useful for NLM targets.
3454 @c man title nlmconv converts object code into an NLM.
3457 @c man begin SYNOPSIS nlmconv
3458 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3459 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3460 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3461 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3462 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3463 @var{infile} @var{outfile}
3467 @c man begin DESCRIPTION nlmconv
3469 @command{nlmconv} converts the relocatable @samp{i386} object file
3470 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3471 reading @var{headerfile} for NLM header information. For instructions
3472 on writing the NLM command file language used in header files, see the
3473 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3474 Development and Tools Overview}, which is part of the NLM Software
3475 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3476 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3479 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3482 @command{nlmconv} can perform a link step. In other words, you can list
3483 more than one object file for input if you list them in the definitions
3484 file (rather than simply specifying one input file on the command line).
3485 In this case, @command{nlmconv} calls the linker for you.
3489 @c man begin OPTIONS nlmconv
3492 @item -I @var{bfdname}
3493 @itemx --input-target=@var{bfdname}
3494 Object format of the input file. @command{nlmconv} can usually determine
3495 the format of a given file (so no default is necessary).
3496 @xref{Target Selection}, for more information.
3498 @item -O @var{bfdname}
3499 @itemx --output-target=@var{bfdname}
3500 Object format of the output file. @command{nlmconv} infers the output
3501 format based on the input format, e.g. for a @samp{i386} input file the
3502 output format is @samp{nlm32-i386}.
3503 @xref{Target Selection}, for more information.
3505 @item -T @var{headerfile}
3506 @itemx --header-file=@var{headerfile}
3507 Reads @var{headerfile} for NLM header information. For instructions on
3508 writing the NLM command file language used in header files, see@ see the
3509 @samp{linkers} section, of the @cite{NLM Development and Tools
3510 Overview}, which is part of the NLM Software Developer's Kit, available
3515 Displays (on standard error) the linker command line used by @command{nlmconv}.
3517 @item -l @var{linker}
3518 @itemx --linker=@var{linker}
3519 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3524 Prints a usage summary.
3528 Prints the version number for @command{nlmconv}.
3534 @c man begin SEEALSO nlmconv
3535 the Info entries for @file{binutils}.
3542 @command{windmc} may be used to generator Windows message resources.
3545 @emph{Warning:} @command{windmc} is not always built as part of the binary
3546 utilities, since it is only useful for Windows targets.
3549 @c man title windmc generates Windows message resources.
3552 @c man begin SYNOPSIS windmc
3553 windmc [options] input-file
3557 @c man begin DESCRIPTION windmc
3559 @command{windmc} reads message definitions from an input file (.mc) and
3560 translate them into a set of output files. The output files may be of
3565 A C header file containing the message definitions.
3568 A resource file compilable by the @command{windres} tool.
3571 One or more binary files containing the resource data for a specific
3575 A C include file that maps message id's to their symbolic name.
3578 The exact description of these different formats is available in
3579 documentation from Microsoft.
3581 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3582 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3583 Windows Message Compiler.
3587 @c man begin OPTIONS windmc
3592 Specifies that the input file specified is ASCII. This is the default
3597 Specifies that messages in the output @code{bin} files should be in ASCII
3602 Specifies that @code{bin} filenames should have to be prefixed by the
3603 basename of the source file.
3607 Sets the customer bit in all message id's.
3609 @item -C @var{codepage}
3610 @itemx --codepage_in @var{codepage}
3611 Sets the default codepage to be used to convert input file to UTF16. The
3612 default is ocdepage 1252.
3615 @itemx --decimal_values
3616 Outputs the constants in the header file in decimal. Default is using
3620 @itemx --extension @var{ext}
3621 The extension for the header file. The default is .h extension.
3623 @item -F @var{target}
3624 @itemx --target @var{target}
3625 Specify the BFD format to use for a bin file as output. This
3626 is a BFD target name; you can use the @option{--help} option to see a list
3627 of supported targets. Normally @command{windmc} will use the default
3628 format, which is the first one listed by the @option{--help} option.
3630 @ref{Target Selection}.
3634 @itemx --headerdir @var{path}
3635 The target directory of the generated header file. The default is the
3640 Displays a list of command line options and then exits.
3642 @item -m @var{characters}
3643 @itemx --maxlength @var{characters}
3644 Instructs @command{windmc} to generate a warning if the length
3645 of any message exceeds the number specified.
3648 @itemx --nullterminate
3649 Terminate message text in @code{bin} files by zero. By default they are
3650 terminated by CR/LF.
3653 @itemx --hresult_use
3654 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3655 file, using HRESULT definitions. Status codes are used if the flag is not
3658 @item -O @var{codepage}
3659 @itemx --codepage_out @var{codepage}
3660 Sets the default codepage to be used to output text files. The default
3664 @itemx --rcdir @var{path}
3665 The target directory for the generated @code{rc} script and the generated
3666 @code{bin} files that the resource compiler script includes. The default
3667 is the current directory.
3671 Specifies that the input file is UTF16.
3674 @itemx --unicode_out
3675 Specifies that messages in the output @code{bin} file should be in UTF16
3676 format. This is the default behaviour.
3680 Enable verbose mode.
3684 Prints the version number for @command{windmc}.
3687 @itemx --xdgb @var{path}
3688 The path of the @code{dbg} C include file that maps message id's to the
3689 symbolic name. No such file is generated without specifying the switch.
3695 @c man begin SEEALSO windmc
3696 the Info entries for @file{binutils}.
3703 @command{windres} may be used to manipulate Windows resources.
3706 @emph{Warning:} @command{windres} is not always built as part of the binary
3707 utilities, since it is only useful for Windows targets.
3710 @c man title windres manipulate Windows resources.
3713 @c man begin SYNOPSIS windres
3714 windres [options] [input-file] [output-file]
3718 @c man begin DESCRIPTION windres
3720 @command{windres} reads resources from an input file and copies them into
3721 an output file. Either file may be in one of three formats:
3725 A text format read by the Resource Compiler.
3728 A binary format generated by the Resource Compiler.
3731 A COFF object or executable.
3734 The exact description of these different formats is available in
3735 documentation from Microsoft.
3737 When @command{windres} converts from the @code{rc} format to the @code{res}
3738 format, it is acting like the Windows Resource Compiler. When
3739 @command{windres} converts from the @code{res} format to the @code{coff}
3740 format, it is acting like the Windows @code{CVTRES} program.
3742 When @command{windres} generates an @code{rc} file, the output is similar
3743 but not identical to the format expected for the input. When an input
3744 @code{rc} file refers to an external filename, an output @code{rc} file
3745 will instead include the file contents.
3747 If the input or output format is not specified, @command{windres} will
3748 guess based on the file name, or, for the input file, the file contents.
3749 A file with an extension of @file{.rc} will be treated as an @code{rc}
3750 file, a file with an extension of @file{.res} will be treated as a
3751 @code{res} file, and a file with an extension of @file{.o} or
3752 @file{.exe} will be treated as a @code{coff} file.
3754 If no output file is specified, @command{windres} will print the resources
3755 in @code{rc} format to standard output.
3757 The normal use is for you to write an @code{rc} file, use @command{windres}
3758 to convert it to a COFF object file, and then link the COFF file into
3759 your application. This will make the resources described in the
3760 @code{rc} file available to Windows.
3764 @c man begin OPTIONS windres
3767 @item -i @var{filename}
3768 @itemx --input @var{filename}
3769 The name of the input file. If this option is not used, then
3770 @command{windres} will use the first non-option argument as the input file
3771 name. If there are no non-option arguments, then @command{windres} will
3772 read from standard input. @command{windres} can not read a COFF file from
3775 @item -o @var{filename}
3776 @itemx --output @var{filename}
3777 The name of the output file. If this option is not used, then
3778 @command{windres} will use the first non-option argument, after any used
3779 for the input file name, as the output file name. If there is no
3780 non-option argument, then @command{windres} will write to standard output.
3781 @command{windres} can not write a COFF file to standard output. Note,
3782 for compatibility with @command{rc} the option @option{-fo} is also
3783 accepted, but its use is not recommended.
3785 @item -J @var{format}
3786 @itemx --input-format @var{format}
3787 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3788 @samp{coff}. If no input format is specified, @command{windres} will
3789 guess, as described above.
3791 @item -O @var{format}
3792 @itemx --output-format @var{format}
3793 The output format to generate. @var{format} may be @samp{res},
3794 @samp{rc}, or @samp{coff}. If no output format is specified,
3795 @command{windres} will guess, as described above.
3797 @item -F @var{target}
3798 @itemx --target @var{target}
3799 Specify the BFD format to use for a COFF file as input or output. This
3800 is a BFD target name; you can use the @option{--help} option to see a list
3801 of supported targets. Normally @command{windres} will use the default
3802 format, which is the first one listed by the @option{--help} option.
3804 @ref{Target Selection}.
3807 @item --preprocessor @var{program}
3808 When @command{windres} reads an @code{rc} file, it runs it through the C
3809 preprocessor first. This option may be used to specify the preprocessor
3810 to use, including any leading arguments. The default preprocessor
3811 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3813 @item --preprocessor-arg @var{option}
3814 When @command{windres} reads an @code{rc} file, it runs it through
3815 the C preprocessor first. This option may be used to specify additional
3816 text to be passed to preprocessor on its command line.
3817 This option can be used multiple times to add multiple options to the
3818 preprocessor command line.
3820 @item -I @var{directory}
3821 @itemx --include-dir @var{directory}
3822 Specify an include directory to use when reading an @code{rc} file.
3823 @command{windres} will pass this to the preprocessor as an @option{-I}
3824 option. @command{windres} will also search this directory when looking for
3825 files named in the @code{rc} file. If the argument passed to this command
3826 matches any of the supported @var{formats} (as described in the @option{-J}
3827 option), it will issue a deprecation warning, and behave just like the
3828 @option{-J} option. New programs should not use this behaviour. If a
3829 directory happens to match a @var{format}, simple prefix it with @samp{./}
3830 to disable the backward compatibility.
3832 @item -D @var{target}
3833 @itemx --define @var{sym}[=@var{val}]
3834 Specify a @option{-D} option to pass to the preprocessor when reading an
3837 @item -U @var{target}
3838 @itemx --undefine @var{sym}
3839 Specify a @option{-U} option to pass to the preprocessor when reading an
3843 Ignored for compatibility with rc.
3846 Enable verbose mode. This tells you what the preprocessor is if you
3850 @item --codepage @var{val}
3851 Specify the default codepage to use when reading an @code{rc} file.
3852 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3853 codepage code. The valid range is from zero up to 0xffff, but the
3854 validity of the codepage is host and configuration dependent.
3857 @item --language @var{val}
3858 Specify the default language to use when reading an @code{rc} file.
3859 @var{val} should be a hexadecimal language code. The low eight bits are
3860 the language, and the high eight bits are the sublanguage.
3862 @item --use-temp-file
3863 Use a temporary file to instead of using popen to read the output of
3864 the preprocessor. Use this option if the popen implementation is buggy
3865 on the host (eg., certain non-English language versions of Windows 95 and
3866 Windows 98 are known to have buggy popen where the output will instead
3869 @item --no-use-temp-file
3870 Use popen, not a temporary file, to read the output of the preprocessor.
3871 This is the default behaviour.
3875 Prints a usage summary.
3879 Prints the version number for @command{windres}.
3882 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3883 this will turn on parser debugging.
3889 @c man begin SEEALSO windres
3890 the Info entries for @file{binutils}.
3899 @command{dlltool} is used to create the files needed to create dynamic
3900 link libraries (DLLs) on systems which understand PE format image
3901 files such as Windows. A DLL contains an export table which contains
3902 information that the runtime loader needs to resolve references from a
3903 referencing program.
3905 The export table is generated by this program by reading in a
3906 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3907 will be in the DLL. A @file{.o} file can contain information in
3908 special @samp{.drectve} sections with export information.
3911 @emph{Note:} @command{dlltool} is not always built as part of the
3912 binary utilities, since it is only useful for those targets which
3916 @c man title dlltool Create files needed to build and use DLLs.
3919 @c man begin SYNOPSIS dlltool
3920 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3921 [@option{-b}|@option{--base-file} @var{base-file-name}]
3922 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3923 [@option{-z}|@option{--output-def} @var{def-file-name}]
3924 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3925 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
3926 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3927 [@option{--exclude-symbols} @var{list}]
3928 [@option{--no-default-excludes}]
3929 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3930 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3931 [@option{-a}|@option{--add-indirect}]
3932 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3933 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3934 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3935 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
3936 [@option{--use-nul-prefixed-import-tables}]
3937 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
3938 [@option{-i}|@option{--interwork}]
3939 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3940 [@option{-v}|@option{--verbose}]
3941 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3942 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
3943 [object-file @dots{}]
3947 @c man begin DESCRIPTION dlltool
3949 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3950 @option{-b} options as well as object files specified on the command
3951 line. It then processes these inputs and if the @option{-e} option has
3952 been specified it creates a exports file. If the @option{-l} option
3953 has been specified it creates a library file and if the @option{-z} option
3954 has been specified it creates a def file. Any or all of the @option{-e},
3955 @option{-l} and @option{-z} options can be present in one invocation of
3958 When creating a DLL, along with the source for the DLL, it is necessary
3959 to have three other files. @command{dlltool} can help with the creation of
3962 The first file is a @file{.def} file which specifies which functions are
3963 exported from the DLL, which functions the DLL imports, and so on. This
3964 is a text file and can be created by hand, or @command{dlltool} can be used
3965 to create it using the @option{-z} option. In this case @command{dlltool}
3966 will scan the object files specified on its command line looking for
3967 those functions which have been specially marked as being exported and
3968 put entries for them in the @file{.def} file it creates.
3970 In order to mark a function as being exported from a DLL, it needs to
3971 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3972 section of the object file. This can be done in C by using the
3976 asm (".section .drectve");
3977 asm (".ascii \"-export:my_func\"");
3979 int my_func (void) @{ @dots{} @}
3982 The second file needed for DLL creation is an exports file. This file
3983 is linked with the object files that make up the body of the DLL and it
3984 handles the interface between the DLL and the outside world. This is a
3985 binary file and it can be created by giving the @option{-e} option to
3986 @command{dlltool} when it is creating or reading in a @file{.def} file.
3988 The third file needed for DLL creation is the library file that programs
3989 will link with in order to access the functions in the DLL (an `import
3990 library'). This file can be created by giving the @option{-l} option to
3991 dlltool when it is creating or reading in a @file{.def} file.
3993 If the @option{-y} option is specified, dlltool generates a delay-import
3994 library that can be used instead of the normal import library to allow
3995 a program to link to the dll only as soon as an imported function is
3996 called for the first time. The resulting executable will need to be
3997 linked to the static delayimp library containing __delayLoadHelper2(),
3998 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4000 @command{dlltool} builds the library file by hand, but it builds the
4001 exports file by creating temporary files containing assembler statements
4002 and then assembling these. The @option{-S} command line option can be
4003 used to specify the path to the assembler that dlltool will use,
4004 and the @option{-f} option can be used to pass specific flags to that
4005 assembler. The @option{-n} can be used to prevent dlltool from deleting
4006 these temporary assembler files when it is done, and if @option{-n} is
4007 specified twice then this will prevent dlltool from deleting the
4008 temporary object files it used to build the library.
4010 Here is an example of creating a DLL from a source file @samp{dll.c} and
4011 also creating a program (from an object file called @samp{program.o})
4016 dlltool -e exports.o -l dll.lib dll.o
4017 gcc dll.o exports.o -o dll.dll
4018 gcc program.o dll.lib -o program
4022 @command{dlltool} may also be used to query an existing import library
4023 to determine the name of the DLL to which it is associated. See the
4024 description of the @option{-I} or @option{--identify} option.
4028 @c man begin OPTIONS dlltool
4030 The command line options have the following meanings:
4034 @item -d @var{filename}
4035 @itemx --input-def @var{filename}
4036 @cindex input .def file
4037 Specifies the name of a @file{.def} file to be read in and processed.
4039 @item -b @var{filename}
4040 @itemx --base-file @var{filename}
4042 Specifies the name of a base file to be read in and processed. The
4043 contents of this file will be added to the relocation section in the
4044 exports file generated by dlltool.
4046 @item -e @var{filename}
4047 @itemx --output-exp @var{filename}
4048 Specifies the name of the export file to be created by dlltool.
4050 @item -z @var{filename}
4051 @itemx --output-def @var{filename}
4052 Specifies the name of the @file{.def} file to be created by dlltool.
4054 @item -l @var{filename}
4055 @itemx --output-lib @var{filename}
4056 Specifies the name of the library file to be created by dlltool.
4058 @item -y @var{filename}
4059 @itemx --output-delaylib @var{filename}
4060 Specifies the name of the delay-import library file to be created by dlltool.
4062 @item --export-all-symbols
4063 Treat all global and weak defined symbols found in the input object
4064 files as symbols to be exported. There is a small list of symbols which
4065 are not exported by default; see the @option{--no-default-excludes}
4066 option. You may add to the list of symbols to not export by using the
4067 @option{--exclude-symbols} option.
4069 @item --no-export-all-symbols
4070 Only export symbols explicitly listed in an input @file{.def} file or in
4071 @samp{.drectve} sections in the input object files. This is the default
4072 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4073 attributes in the source code.
4075 @item --exclude-symbols @var{list}
4076 Do not export the symbols in @var{list}. This is a list of symbol names
4077 separated by comma or colon characters. The symbol names should not
4078 contain a leading underscore. This is only meaningful when
4079 @option{--export-all-symbols} is used.
4081 @item --no-default-excludes
4082 When @option{--export-all-symbols} is used, it will by default avoid
4083 exporting certain special symbols. The current list of symbols to avoid
4084 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4085 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4086 to go ahead and export these special symbols. This is only meaningful
4087 when @option{--export-all-symbols} is used.
4090 @itemx --as @var{path}
4091 Specifies the path, including the filename, of the assembler to be used
4092 to create the exports file.
4094 @item -f @var{options}
4095 @itemx --as-flags @var{options}
4096 Specifies any specific command line options to be passed to the
4097 assembler when building the exports file. This option will work even if
4098 the @option{-S} option is not used. This option only takes one argument,
4099 and if it occurs more than once on the command line, then later
4100 occurrences will override earlier occurrences. So if it is necessary to
4101 pass multiple options to the assembler they should be enclosed in
4105 @itemx --dll-name @var{name}
4106 Specifies the name to be stored in the @file{.def} file as the name of
4107 the DLL when the @option{-e} option is used. If this option is not
4108 present, then the filename given to the @option{-e} option will be
4109 used as the name of the DLL.
4111 @item -m @var{machine}
4112 @itemx -machine @var{machine}
4113 Specifies the type of machine for which the library file should be
4114 built. @command{dlltool} has a built in default type, depending upon how
4115 it was created, but this option can be used to override that. This is
4116 normally only useful when creating DLLs for an ARM processor, when the
4117 contents of the DLL are actually encode using Thumb instructions.
4120 @itemx --add-indirect
4121 Specifies that when @command{dlltool} is creating the exports file it
4122 should add a section which allows the exported functions to be
4123 referenced without using the import library. Whatever the hell that
4127 @itemx --add-underscore
4128 Specifies that when @command{dlltool} is creating the exports file it
4129 should prepend an underscore to the names of @emph{all} exported symbols.
4131 @item --no-leading-underscore
4132 @item --leading-underscore
4133 Specifies whether standard symbol should be forced to be prefixed, or
4136 @item --add-stdcall-underscore
4137 Specifies that when @command{dlltool} is creating the exports file it
4138 should prepend an underscore to the names of exported @emph{stdcall}
4139 functions. Variable names and non-stdcall function names are not modified.
4140 This option is useful when creating GNU-compatible import libs for third
4141 party DLLs that were built with MS-Windows tools.
4145 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4146 of stdcall functions that will be imported from the DLL. This is
4147 useful when creating an import library for a DLL which exports stdcall
4148 functions but without the usual @samp{@@<number>} symbol name suffix.
4150 This does not change the naming of symbols provided by the import library
4151 to programs linked against it, but only the entries in the import table
4152 (ie the .idata section).
4155 @itemx --add-stdcall-alias
4156 Specifies that when @command{dlltool} is creating the exports file it
4157 should add aliases for stdcall symbols without @samp{@@ <number>}
4158 in addition to the symbols with @samp{@@ <number>}.
4161 @itemx --ext-prefix-alias @var{prefix}
4162 Causes @command{dlltool} to create external aliases for all DLL
4163 imports with the specified prefix. The aliases are created for both
4164 external and import symbols with no leading underscore.
4168 Specifies that when @command{dlltool} is creating the exports and library
4169 files it should omit the @code{.idata4} section. This is for compatibility
4170 with certain operating systems.
4172 @item --use-nul-prefixed-import-tables
4173 Specifies that when @command{dlltool} is creating the exports and library
4174 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4175 element. This emulates old gnu import library generation of
4176 @code{dlltool}. By default this option is turned off.
4180 Specifies that when @command{dlltool} is creating the exports and library
4181 files it should omit the @code{.idata5} section. This is for compatibility
4182 with certain operating systems.
4184 @item -I @var{filename}
4185 @itemx --identify @var{filename}
4186 Specifies that @command{dlltool} should inspect the import library
4187 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4188 of the associated DLL(s). This can be performed in addition to any
4189 other operations indicated by the other options and arguments.
4190 @command{dlltool} fails if the import library does not exist or is not
4191 actually an import library. See also @option{--identify-strict}.
4193 @item --identify-strict
4194 Modifies the behavior of the @option{--identify} option, such
4195 that an error is reported if @var{filename} is associated with
4200 Specifies that @command{dlltool} should mark the objects in the library
4201 file and exports file that it produces as supporting interworking
4202 between ARM and Thumb code.
4206 Makes @command{dlltool} preserve the temporary assembler files it used to
4207 create the exports file. If this option is repeated then dlltool will
4208 also preserve the temporary object files it uses to create the library
4211 @item -t @var{prefix}
4212 @itemx --temp-prefix @var{prefix}
4213 Makes @command{dlltool} use @var{prefix} when constructing the names of
4214 temporary assembler and object files. By default, the temp file prefix
4215 is generated from the pid.
4219 Make dlltool describe what it is doing.
4223 Displays a list of command line options and then exits.
4227 Displays dlltool's version number and then exits.
4234 * def file format:: The format of the dlltool @file{.def} file
4237 @node def file format
4238 @section The format of the @command{dlltool} @file{.def} file
4240 A @file{.def} file contains any number of the following commands:
4244 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4245 The result is going to be named @var{name}@code{.exe}.
4247 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4248 The result is going to be named @var{name}@code{.dll}.
4249 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4250 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4253 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4254 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4255 Declares @var{name1} as an exported symbol from the DLL, with optional
4256 ordinal number @var{integer}, or declares @var{name1} as an alias
4257 (forward) of the function @var{external-name} in the DLL.
4258 If @var{its_name} is specified, this name is used as string in export table.
4260 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4261 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4262 If you want to use LIBRARY as name then you need to quote it.
4264 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) [ == ) @var{its_name} @code{]} *}
4265 Declares that @var{external-name} or the exported function whose
4266 ordinal number is @var{integer} is to be imported from the file
4267 @var{module-name}. If @var{internal-name} is specified then this is
4268 the name that the imported function will be referred to in the body of
4270 If @var{its_name} is specified, this name is used as string in import table.
4271 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4272 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4273 If you want to use LIBRARY as name then you need to quote it.
4275 @item @code{DESCRIPTION} @var{string}
4276 Puts @var{string} into the output @file{.exp} file in the
4277 @code{.rdata} section.
4279 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4280 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4281 Generates @code{--stack} or @code{--heap}
4282 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4283 section. The linker will see this and act upon it.
4285 @item @code{CODE} @var{attr} @code{+}
4286 @item @code{DATA} @var{attr} @code{+}
4287 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4288 Generates @code{--attr} @var{section-name} @var{attr} in the output
4289 @code{.drectve} section, where @var{attr} is one of @code{READ},
4290 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4291 this and act upon it.
4296 @c man begin SEEALSO dlltool
4297 The Info pages for @file{binutils}.
4304 @cindex ELF file information
4307 @c man title readelf Displays information about ELF files.
4310 @c man begin SYNOPSIS readelf
4311 readelf [@option{-a}|@option{--all}]
4312 [@option{-h}|@option{--file-header}]
4313 [@option{-l}|@option{--program-headers}|@option{--segments}]
4314 [@option{-S}|@option{--section-headers}|@option{--sections}]
4315 [@option{-g}|@option{--section-groups}]
4316 [@option{-t}|@option{--section-details}]
4317 [@option{-e}|@option{--headers}]
4318 [@option{-s}|@option{--syms}|@option{--symbols}]
4319 [@option{--dyn-syms}]
4320 [@option{-n}|@option{--notes}]
4321 [@option{-r}|@option{--relocs}]
4322 [@option{-u}|@option{--unwind}]
4323 [@option{-d}|@option{--dynamic}]
4324 [@option{-V}|@option{--version-info}]
4325 [@option{-A}|@option{--arch-specific}]
4326 [@option{-D}|@option{--use-dynamic}]
4327 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4328 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4329 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4330 [@option{-c}|@option{--archive-index}]
4331 [@option{-w[lLiaprmfFsoRt]}|
4332 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
4333 [@option{--dwarf-depth=@var{n}}]
4334 [@option{--dwarf-start=@var{n}}]
4335 [@option{-I}|@option{--histogram}]
4336 [@option{-v}|@option{--version}]
4337 [@option{-W}|@option{--wide}]
4338 [@option{-H}|@option{--help}]
4339 @var{elffile}@dots{}
4343 @c man begin DESCRIPTION readelf
4345 @command{readelf} displays information about one or more ELF format object
4346 files. The options control what particular information to display.
4348 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4349 64-bit ELF files are supported, as are archives containing ELF files.
4351 This program performs a similar function to @command{objdump} but it
4352 goes into more detail and it exists independently of the @sc{bfd}
4353 library, so if there is a bug in @sc{bfd} then readelf will not be
4358 @c man begin OPTIONS readelf
4360 The long and short forms of options, shown here as alternatives, are
4361 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4367 Equivalent to specifying @option{--file-header},
4368 @option{--program-headers}, @option{--sections}, @option{--symbols},
4369 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4370 @option{--version-info}.
4373 @itemx --file-header
4374 @cindex ELF file header information
4375 Displays the information contained in the ELF header at the start of the
4379 @itemx --program-headers
4381 @cindex ELF program header information
4382 @cindex ELF segment information
4383 Displays the information contained in the file's segment headers, if it
4388 @itemx --section-headers
4389 @cindex ELF section information
4390 Displays the information contained in the file's section headers, if it
4394 @itemx --section-groups
4395 @cindex ELF section group information
4396 Displays the information contained in the file's section groups, if it
4400 @itemx --section-details
4401 @cindex ELF section information
4402 Displays the detailed section information. Implies @option{-S}.
4407 @cindex ELF symbol table information
4408 Displays the entries in symbol table section of the file, if it has one.
4411 @cindex ELF dynamic symbol table information
4412 Displays the entries in dynamic symbol table section of the file, if it
4417 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4422 Displays the contents of the NOTE segments and/or sections, if any.
4426 @cindex ELF reloc information
4427 Displays the contents of the file's relocation section, if it has one.
4431 @cindex unwind information
4432 Displays the contents of the file's unwind section, if it has one. Only
4433 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4434 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4438 @cindex ELF dynamic section information
4439 Displays the contents of the file's dynamic section, if it has one.
4442 @itemx --version-info
4443 @cindex ELF version sections information
4444 Displays the contents of the version sections in the file, it they
4448 @itemx --arch-specific
4449 Displays architecture-specific information in the file, if there
4453 @itemx --use-dynamic
4454 When displaying symbols, this option makes @command{readelf} use the
4455 symbol hash tables in the file's dynamic section, rather than the
4456 symbol table sections.
4458 @item -x <number or name>
4459 @itemx --hex-dump=<number or name>
4460 Displays the contents of the indicated section as a hexadecimal bytes.
4461 A number identifies a particular section by index in the section table;
4462 any other string identifies all sections with that name in the object file.
4464 @item -R <number or name>
4465 @itemx --relocated-dump=<number or name>
4466 Displays the contents of the indicated section as a hexadecimal
4467 bytes. A number identifies a particular section by index in the
4468 section table; any other string identifies all sections with that name
4469 in the object file. The contents of the section will be relocated
4470 before they are displayed.
4472 @item -p <number or name>
4473 @itemx --string-dump=<number or name>
4474 Displays the contents of the indicated section as printable strings.
4475 A number identifies a particular section by index in the section table;
4476 any other string identifies all sections with that name in the object file.
4479 @itemx --archive-index
4480 @cindex Archive file symbol index information
4481 Displays the file symbol index information contained in the header part
4482 of binary archives. Performs the same function as the @option{t}
4483 command to @command{ar}, but without using the BFD library. @xref{ar}.
4485 @item -w[lLiaprmfFsoRt]
4486 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
4487 Displays the contents of the debug sections in the file, if any are
4488 present. If one of the optional letters or words follows the switch
4489 then only data found in those specific sections will be dumped.
4491 Note that there is no single letter option to display the content of
4492 trace sections or .gdb_index.
4494 Note: the @option{=decodedline} option will display the interpreted
4495 contents of a .debug_line section whereas the @option{=rawline} option
4496 dumps the contents in a raw format.
4498 Note: the @option{=frames-interp} option will display the interpreted
4499 contents of a .debug_frame section whereas the @option{=frames} option
4500 dumps the contents in a raw format.
4502 Note: the output from the @option{=info} option can also be affected
4503 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4505 @item --dwarf-depth=@var{n}
4506 Limit the dump of the @code{.debug_info} section to @var{n} children.
4507 This is only useful with @option{--debug-dump=info}. The default is
4508 to print all DIEs; the special value 0 for @var{n} will also have this
4511 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4512 levels will not be printed. The range for @var{n} is zero-based.
4514 @item --dwarf-start=@var{n}
4515 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4516 useful with @option{--debug-dump=info}.
4518 If specified, this option will suppress printing of any header
4519 information and all DIEs before the DIE numbered @var{n}. Only
4520 siblings and children of the specified DIE will be printed.
4522 This can be used in conjunction with @option{--dwarf-depth}.
4526 Display a histogram of bucket list lengths when displaying the contents
4527 of the symbol tables.
4531 Display the version number of readelf.
4535 Don't break output lines to fit into 80 columns. By default
4536 @command{readelf} breaks section header and segment listing lines for
4537 64-bit ELF files, so that they fit into 80 columns. This option causes
4538 @command{readelf} to print each section header resp. each segment one a
4539 single line, which is far more readable on terminals wider than 80 columns.
4543 Display the command line options understood by @command{readelf}.
4550 @c man begin SEEALSO readelf
4551 objdump(1), and the Info entries for @file{binutils}.
4558 @cindex Update ELF header
4561 @c man title elfedit Update the ELF header of ELF files.
4564 @c man begin SYNOPSIS elfedit
4565 elfedit [@option{--input-mach=}@var{machine}]
4566 [@option{--input-type=}@var{type}]
4567 [@option{--input-osabi=}@var{osabi}]
4568 @option{--output-mach=}@var{machine}
4569 @option{--output-type=}@var{type}
4570 @option{--output-osabi=}@var{osabi}
4571 [@option{-v}|@option{--version}]
4572 [@option{-h}|@option{--help}]
4573 @var{elffile}@dots{}
4577 @c man begin DESCRIPTION elfedit
4579 @command{elfedit} updates the ELF header of ELF files which have
4580 the matching ELF machine and file types. The options control how and
4581 which fields in the ELF header should be updated.
4583 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4584 64-bit ELF files are supported, as are archives containing ELF files.
4587 @c man begin OPTIONS elfedit
4589 The long and short forms of options, shown here as alternatives, are
4590 equivalent. At least one of the @option{--output-mach},
4591 @option{--output-type} and @option{--output-osabi} options must be given.
4595 @item --input-mach=@var{machine}
4596 Set the matching input ELF machine type to @var{machine}. If
4597 @option{--input-mach} isn't specified, it will match any ELF
4600 The supported ELF machine types are, @var{L1OM}, @var{K1OM} and
4603 @item --output-mach=@var{machine}
4604 Change the ELF machine type in the ELF header to @var{machine}. The
4605 supported ELF machine types are the same as @option{--input-mach}.
4607 @item --input-type=@var{type}
4608 Set the matching input ELF file type to @var{type}. If
4609 @option{--input-type} isn't specified, it will match any ELF file types.
4611 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4613 @item --output-type=@var{type}
4614 Change the ELF file type in the ELF header to @var{type}. The
4615 supported ELF types are the same as @option{--input-type}.
4617 @item --input-osabi=@var{osabi}
4618 Set the matching input ELF file OSABI to @var{osabi}. If
4619 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4621 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4622 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4623 @var{Solaris}, @var{AIX}, @var{Irix},
4624 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4625 @var{NSK}, @var{AROS} and @var{FenixOS}.
4627 @item --output-osabi=@var{osabi}
4628 Change the ELF OSABI in the ELF header to @var{osabi}. The
4629 supported ELF OSABI are the same as @option{--input-osabi}.
4633 Display the version number of @command{elfedit}.
4637 Display the command line options understood by @command{elfedit}.
4644 @c man begin SEEALSO elfedit
4645 readelf(1), and the Info entries for @file{binutils}.
4649 @node Common Options
4650 @chapter Common Options
4652 The following command-line options are supported by all of the
4653 programs described in this manual.
4655 @c man begin OPTIONS
4657 @include at-file.texi
4661 Display the command-line options supported by the program.
4664 Display the version number of the program.
4666 @c man begin OPTIONS
4670 @node Selecting the Target System
4671 @chapter Selecting the Target System
4673 You can specify two aspects of the target system to the @sc{gnu}
4674 binary file utilities, each in several ways:
4684 In the following summaries, the lists of ways to specify values are in
4685 order of decreasing precedence. The ways listed first override those
4688 The commands to list valid values only list the values for which the
4689 programs you are running were configured. If they were configured with
4690 @option{--enable-targets=all}, the commands list most of the available
4691 values, but a few are left out; not all targets can be configured in at
4692 once because some of them can only be configured @dfn{native} (on hosts
4693 with the same type as the target system).
4696 * Target Selection::
4697 * Architecture Selection::
4700 @node Target Selection
4701 @section Target Selection
4703 A @dfn{target} is an object file format. A given target may be
4704 supported for multiple architectures (@pxref{Architecture Selection}).
4705 A target selection may also have variations for different operating
4706 systems or architectures.
4708 The command to list valid target values is @samp{objdump -i}
4709 (the first column of output contains the relevant information).
4711 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4712 @samp{a.out-sunos-big}.
4714 You can also specify a target using a configuration triplet. This is
4715 the same sort of name that is passed to @file{configure} to specify a
4716 target. When you use a configuration triplet as an argument, it must be
4717 fully canonicalized. You can see the canonical version of a triplet by
4718 running the shell script @file{config.sub} which is included with the
4721 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4722 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4724 @subheading @command{objdump} Target
4730 command line option: @option{-b} or @option{--target}
4733 environment variable @code{GNUTARGET}
4736 deduced from the input file
4739 @subheading @command{objcopy} and @command{strip} Input Target
4745 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4748 environment variable @code{GNUTARGET}
4751 deduced from the input file
4754 @subheading @command{objcopy} and @command{strip} Output Target
4760 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4763 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4766 environment variable @code{GNUTARGET}
4769 deduced from the input file
4772 @subheading @command{nm}, @command{size}, and @command{strings} Target
4778 command line option: @option{--target}
4781 environment variable @code{GNUTARGET}
4784 deduced from the input file
4787 @node Architecture Selection
4788 @section Architecture Selection
4790 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4791 to run. Its name may contain a colon, separating the name of the
4792 processor family from the name of the particular @sc{cpu}.
4794 The command to list valid architecture values is @samp{objdump -i} (the
4795 second column contains the relevant information).
4797 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4799 @subheading @command{objdump} Architecture
4805 command line option: @option{-m} or @option{--architecture}
4808 deduced from the input file
4811 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4817 deduced from the input file
4820 @node Reporting Bugs
4821 @chapter Reporting Bugs
4823 @cindex reporting bugs
4825 Your bug reports play an essential role in making the binary utilities
4828 Reporting a bug may help you by bringing a solution to your problem, or
4829 it may not. But in any case the principal function of a bug report is
4830 to help the entire community by making the next version of the binary
4831 utilities work better. Bug reports are your contribution to their
4834 In order for a bug report to serve its purpose, you must include the
4835 information that enables us to fix the bug.
4838 * Bug Criteria:: Have you found a bug?
4839 * Bug Reporting:: How to report bugs
4843 @section Have You Found a Bug?
4844 @cindex bug criteria
4846 If you are not sure whether you have found a bug, here are some guidelines:
4849 @cindex fatal signal
4852 If a binary utility gets a fatal signal, for any input whatever, that is
4853 a bug. Reliable utilities never crash.
4855 @cindex error on valid input
4857 If a binary utility produces an error message for valid input, that is a
4861 If you are an experienced user of binary utilities, your suggestions for
4862 improvement are welcome in any case.
4866 @section How to Report Bugs
4868 @cindex bugs, reporting
4870 A number of companies and individuals offer support for @sc{gnu}
4871 products. If you obtained the binary utilities from a support
4872 organization, we recommend you contact that organization first.
4874 You can find contact information for many support companies and
4875 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4879 In any event, we also recommend that you send bug reports for the binary
4880 utilities to @value{BUGURL}.
4883 The fundamental principle of reporting bugs usefully is this:
4884 @strong{report all the facts}. If you are not sure whether to state a
4885 fact or leave it out, state it!
4887 Often people omit facts because they think they know what causes the
4888 problem and assume that some details do not matter. Thus, you might
4889 assume that the name of a file you use in an example does not matter.
4890 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4891 a stray memory reference which happens to fetch from the location where
4892 that pathname is stored in memory; perhaps, if the pathname were
4893 different, the contents of that location would fool the utility into
4894 doing the right thing despite the bug. Play it safe and give a
4895 specific, complete example. That is the easiest thing for you to do,
4896 and the most helpful.
4898 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4899 it is new to us. Therefore, always write your bug reports on the assumption
4900 that the bug has not been reported previously.
4902 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4903 bell?'' This cannot help us fix a bug, so it is basically useless. We
4904 respond by asking for enough details to enable us to investigate.
4905 You might as well expedite matters by sending them to begin with.
4907 To enable us to fix the bug, you should include all these things:
4911 The version of the utility. Each utility announces it if you start it
4912 with the @option{--version} argument.
4914 Without this, we will not know whether there is any point in looking for
4915 the bug in the current version of the binary utilities.
4918 Any patches you may have applied to the source, including any patches
4919 made to the @code{BFD} library.
4922 The type of machine you are using, and the operating system name and
4926 What compiler (and its version) was used to compile the utilities---e.g.
4930 The command arguments you gave the utility to observe the bug. To
4931 guarantee you will not omit something important, list them all. A copy
4932 of the Makefile (or the output from make) is sufficient.
4934 If we were to try to guess the arguments, we would probably guess wrong
4935 and then we might not encounter the bug.
4938 A complete input file, or set of input files, that will reproduce the
4939 bug. If the utility is reading an object file or files, then it is
4940 generally most helpful to send the actual object files.
4942 If the source files were produced exclusively using @sc{gnu} programs
4943 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4944 may be OK to send the source files rather than the object files. In
4945 this case, be sure to say exactly what version of @command{gcc}, or
4946 whatever, was used to produce the object files. Also say how
4947 @command{gcc}, or whatever, was configured.
4950 A description of what behavior you observe that you believe is
4951 incorrect. For example, ``It gets a fatal signal.''
4953 Of course, if the bug is that the utility gets a fatal signal, then we
4954 will certainly notice it. But if the bug is incorrect output, we might
4955 not notice unless it is glaringly wrong. You might as well not give us
4956 a chance to make a mistake.
4958 Even if the problem you experience is a fatal signal, you should still
4959 say so explicitly. Suppose something strange is going on, such as your
4960 copy of the utility is out of sync, or you have encountered a bug in
4961 the C library on your system. (This has happened!) Your copy might
4962 crash and ours would not. If you told us to expect a crash, then when
4963 ours fails to crash, we would know that the bug was not happening for
4964 us. If you had not told us to expect a crash, then we would not be able
4965 to draw any conclusion from our observations.
4968 If you wish to suggest changes to the source, send us context diffs, as
4969 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
4970 option. Always send diffs from the old file to the new file. If you
4971 wish to discuss something in the @command{ld} source, refer to it by
4972 context, not by line number.
4974 The line numbers in our development sources will not match those in your
4975 sources. Your line numbers would convey no useful information to us.
4978 Here are some things that are not necessary:
4982 A description of the envelope of the bug.
4984 Often people who encounter a bug spend a lot of time investigating
4985 which changes to the input file will make the bug go away and which
4986 changes will not affect it.
4988 This is often time consuming and not very useful, because the way we
4989 will find the bug is by running a single example under the debugger
4990 with breakpoints, not by pure deduction from a series of examples.
4991 We recommend that you save your time for something else.
4993 Of course, if you can find a simpler example to report @emph{instead}
4994 of the original one, that is a convenience for us. Errors in the
4995 output will be easier to spot, running under the debugger will take
4996 less time, and so on.
4998 However, simplification is not vital; if you do not want to do this,
4999 report the bug anyway and send us the entire test case you used.
5002 A patch for the bug.
5004 A patch for the bug does help us if it is a good one. But do not omit
5005 the necessary information, such as the test case, on the assumption that
5006 a patch is all we need. We might see problems with your patch and decide
5007 to fix the problem another way, or we might not understand it at all.
5009 Sometimes with programs as complicated as the binary utilities it is
5010 very hard to construct an example that will make the program follow a
5011 certain path through the code. If you do not send us the example, we
5012 will not be able to construct one, so we will not be able to verify that
5015 And if we cannot understand what bug you are trying to fix, or why your
5016 patch should be an improvement, we will not install it. A test case will
5017 help us to understand.
5020 A guess about what the bug is or what it depends on.
5022 Such guesses are usually wrong. Even we cannot guess right about such
5023 things without first using the debugger to find the facts.
5026 @node GNU Free Documentation License
5027 @appendix GNU Free Documentation License
5031 @node Binutils Index
5032 @unnumbered Binutils Index