1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities.
9 * ar: (binutils)ar. Create, modify, and extract from archives
10 * nm: (binutils)nm. List symbols from object files
11 * objcopy: (binutils)objcopy. Copy and translate object files
12 * objdump: (binutils)objdump. Display information from object files
13 * ranlib: (binutils)ranlib. Generate index to archive contents
14 * readelf: (binutils)readelf. Display the contents of ELF format files.
15 * size: (binutils)size. List section sizes and total size
16 * strings: (binutils)strings. List printable strings from files
17 * strip: (binutils)strip. Discard symbols
18 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
19 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
20 * addr2line: (binutils)addr2line. Convert addresses to file and line
21 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
22 * windres: (binutils)windres. Manipulate Windows resources
23 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
29 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
31 Permission is granted to make and distribute verbatim copies of
32 this manual provided the copyright notice and this permission notice
33 are preserved on all copies.
36 Permission is granted to process this file through TeX and print the
37 results, provided the printed document carries a copying permission
38 notice identical to this one except for the removal of this paragraph
39 (this paragraph not being relevant to the printed manual).
43 Permission is granted to copy and distribute modified versions of this
44 manual under the conditions for verbatim copying, provided also that
45 the entire resulting derived work is distributed under the terms of a
46 permission notice identical to this one.
48 Permission is granted to copy and distribute translations of this manual
49 into another language, under the above conditions for modified versions.
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
57 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
59 @c This text may be freely distributed under the terms of the GNU
60 @c General Public License.
63 @setchapternewpage odd
64 @settitle @sc{gnu} Binary Utilities
67 @title The @sc{gnu} Binary Utilities
68 @subtitle Version @value{VERSION}
71 @author Roland H. Pesch
72 @author Jeffrey M. Osier
73 @author Cygnus Support
77 {\parskip=0pt \hfill Cygnus Support\par \hfill
78 \TeX{}info \texinfoversion\par }
81 @vskip 0pt plus 1filll
82 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
84 Permission is granted to make and distribute verbatim copies of
85 this manual provided the copyright notice and this permission notice
86 are preserved on all copies.
88 Permission is granted to copy and distribute modified versions of this
89 manual under the conditions for verbatim copying, provided also that
90 the entire resulting derived work is distributed under the terms of a
91 permission notice identical to this one.
93 Permission is granted to copy and distribute translations of this manual
94 into another language, under the above conditions for modified versions.
101 This brief manual contains preliminary documentation for the @sc{gnu} binary
102 utilities (collectively version @value{VERSION}):
107 Create, modify, and extract from archives
110 List symbols from object files
113 Copy and translate object files
116 Display information from object files
119 Generate index to archive contents
122 Display the contents of ELF format files.
125 List file section sizes and total size
128 List printable strings from files
134 Demangle encoded C++ symbols (on MS-DOS, this program is named
138 Convert addresses into file names and line numbers
141 Convert object code into a Netware Loadable Module
144 Manipulate Windows resources
147 Create the files needed to build and use Dynamic Link Libraries
152 * ar:: Create, modify, and extract from archives
153 * nm:: List symbols from object files
154 * objcopy:: Copy and translate object files
155 * objdump:: Display information from object files
156 * ranlib:: Generate index to archive contents
157 * readelf:: Display the contents of ELF format files.
158 * size:: List section sizes and total size
159 * strings:: List printable strings from files
160 * strip:: Discard symbols
161 * c++filt:: Filter to demangle encoded C++ symbols
162 * cxxfilt: c++filt. MS-DOS name for c++filt
163 * addr2line:: Convert addresses to file and line
164 * nlmconv:: Converts object code into an NLM
165 * windres:: Manipulate Windows resources
166 * dlltool:: Create files needed to build and use DLLs
167 * Selecting The Target System:: How these utilities determine the target.
168 * Reporting Bugs:: Reporting Bugs
177 @cindex collections of files
179 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
180 ar -M [ <mri-script ]
183 The @sc{gnu} @code{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} @code{ar} can maintain archives whose members have names of any
194 length; however, depending on how @code{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 @code{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @code{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 @code{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 @code{ar} called
216 @code{ranlib} can be used to add just the table.
218 @cindex compatibility, @code{ar}
219 @cindex @code{ar} compatibility
220 @sc{gnu} @code{ar} is designed to be compatible with two different
221 facilities. You can control its activity using command-line options,
222 like the different varieties of @code{ar} on Unix systems; or, if you
223 specify the single command-line option @samp{-M}, you can control it
224 with a script supplied via standard input, like the MRI ``librarian''
228 * ar cmdline:: Controlling @code{ar} on the command line
229 * ar scripts:: Controlling @code{ar} with a script
234 @section Controlling @code{ar} on the command line
237 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
240 @cindex Unix compatibility, @code{ar}
241 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
242 arguments to execute: one keyletter specifying the @emph{operation}
243 (optionally accompanied by other keyletters specifying
244 @emph{modifiers}), and the archive name to act on.
246 Most operations can also accept further @var{member} arguments,
247 specifying particular files to operate on.
249 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
250 flags @var{mod} in any order, within the first command-line argument.
252 If you wish, you may begin the first command-line argument with a
255 @cindex operations on archive
256 The @var{p} keyletter specifies what operation to execute; it may be
257 any of the following, but you must specify only one of them:
261 @cindex deleting from archive
262 @emph{Delete} modules from the archive. Specify the names of modules to
263 be deleted as @var{member}@dots{}; the archive is untouched if you
264 specify no files to delete.
266 If you specify the @samp{v} modifier, @code{ar} lists each module
270 @cindex moving in archive
271 Use this operation to @emph{move} members in an archive.
273 The ordering of members in an archive can make a difference in how
274 programs are linked using the library, if a symbol is defined in more
277 If no modifiers are used with @code{m}, any members you name in the
278 @var{member} arguments are moved to the @emph{end} of the archive;
279 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
280 specified place instead.
283 @cindex printing from archive
284 @emph{Print} the specified members of the archive, to the standard
285 output file. If the @samp{v} modifier is specified, show the member
286 name before copying its contents to standard output.
288 If you specify no @var{member} arguments, all the files in the archive are
292 @cindex quick append to archive
293 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
294 @var{archive}, without checking for replacement.
296 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
297 operation; new members are always placed at the end of the archive.
299 The modifier @samp{v} makes @code{ar} list each file as it is appended.
301 Since the point of this operation is speed, the archive's symbol table
302 index is not updated, even if it already existed; you can use @samp{ar s} or
303 @code{ranlib} explicitly to update the symbol table index.
305 However, too many different systems assume quick append rebuilds the
306 index, so GNU ar implements @code{q} as a synonym for @code{r}.
309 @cindex replacement in archive
310 Insert the files @var{member}@dots{} into @var{archive} (with
311 @emph{replacement}). This operation differs from @samp{q} in that any
312 previously existing members are deleted if their names match those being
315 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
316 displays an error message, and leaves undisturbed any existing members
317 of the archive matching that name.
319 By default, new members are added at the end of the file; but you may
320 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
321 placement relative to some existing member.
323 The modifier @samp{v} used with this operation elicits a line of
324 output for each file inserted, along with one of the letters @samp{a} or
325 @samp{r} to indicate whether the file was appended (no old member
326 deleted) or replaced.
329 @cindex contents of archive
330 Display a @emph{table} listing the contents of @var{archive}, or those
331 of the files listed in @var{member}@dots{} that are present in the
332 archive. Normally only the member name is shown; if you also want to
333 see the modes (permissions), timestamp, owner, group, and size, you can
334 request that by also specifying the @samp{v} modifier.
336 If you do not specify a @var{member}, all files in the archive
339 @cindex repeated names in archive
340 @cindex name duplication in archive
341 If there is more than one file with the same name (say, @samp{fie}) in
342 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
343 first instance; to see them all, you must ask for a complete
344 listing---in our example, @samp{ar t b.a}.
345 @c WRS only; per Gumby, this is implementation-dependent, and in a more
346 @c recent case in fact works the other way.
349 @cindex extract from archive
350 @emph{Extract} members (named @var{member}) from the archive. You can
351 use the @samp{v} modifier with this operation, to request that
352 @code{ar} list each name as it extracts it.
354 If you do not specify a @var{member}, all files in the archive
359 A number of modifiers (@var{mod}) may immediately follow the @var{p}
360 keyletter, to specify variations on an operation's behavior:
364 @cindex relative placement in archive
365 Add new files @emph{after} an existing member of the
366 archive. If you use the modifier @samp{a}, the name of an existing archive
367 member must be present as the @var{relpos} argument, before the
368 @var{archive} specification.
371 Add new files @emph{before} an existing member of the
372 archive. If you use the modifier @samp{b}, the name of an existing archive
373 member must be present as the @var{relpos} argument, before the
374 @var{archive} specification. (same as @samp{i}).
377 @cindex creating archives
378 @emph{Create} the archive. The specified @var{archive} is always
379 created if it did not exist, when you request an update. But a warning is
380 issued unless you specify in advance that you expect to create it, by
384 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
385 names of any length. This will cause it to create archives which are
386 not compatible with the native @code{ar} program on some systems. If
387 this is a concern, the @samp{f} modifier may be used to truncate file
388 names when putting them in the archive.
391 Insert new files @emph{before} an existing member of the
392 archive. If you use the modifier @samp{i}, the name of an existing archive
393 member must be present as the @var{relpos} argument, before the
394 @var{archive} specification. (same as @samp{b}).
397 This modifier is accepted but not used.
398 @c whaffor ar l modifier??? presumably compat; with
399 @c what???---doc@@cygnus.com, 25jan91
402 Uses the @var{count} parameter. This is used if there are multiple
403 entries in the archive with the same name. Extract or delete instance
404 @var{count} of the given name from the archive.
407 @cindex dates in archive
408 Preserve the @emph{original} dates of members when extracting them. If
409 you do not specify this modifier, files extracted from the archive
410 are stamped with the time of extraction.
413 Use the full path name when matching names in the archive. @sc{gnu}
414 @code{ar} can not create an archive with a full path name (such archives
415 are not POSIX complaint), but other archive creators can. This option
416 will cause @sc{gnu} @code{ar} to match file names using a complete path
417 name, which can be convenient when extracting a single file from an
418 archive created by another tool.
421 @cindex writing archive index
422 Write an object-file index into the archive, or update an existing one,
423 even if no other change is made to the archive. You may use this modifier
424 flag either with any operation, or alone. Running @samp{ar s} on an
425 archive is equivalent to running @samp{ranlib} on it.
428 @cindex not writing archive index
429 Do not generate an archive symbol table. This can speed up building a
430 large library in several steps. The resulting archive can not be used
431 with the linker. In order to build a symbol table, you must omit the
432 @samp{S} modifier on the last execution of @samp{ar}, or you must run
433 @samp{ranlib} on the archive.
436 @cindex updating an archive
437 Normally, @samp{ar r}@dots{} inserts all files
438 listed into the archive. If you would like to insert @emph{only} those
439 of the files you list that are newer than existing members of the same
440 names, use this modifier. The @samp{u} modifier is allowed only for the
441 operation @samp{r} (replace). In particular, the combination @samp{qu} is
442 not allowed, since checking the timestamps would lose any speed
443 advantage from the operation @samp{q}.
446 This modifier requests the @emph{verbose} version of an operation. Many
447 operations display additional information, such as filenames processed,
448 when the modifier @samp{v} is appended.
451 This modifier shows the version number of @code{ar}.
455 @section Controlling @code{ar} with a script
458 ar -M [ <@var{script} ]
461 @cindex MRI compatibility, @code{ar}
462 @cindex scripts, @code{ar}
463 If you use the single command-line option @samp{-M} with @code{ar}, you
464 can control its operation with a rudimentary command language. This
465 form of @code{ar} operates interactively if standard input is coming
466 directly from a terminal. During interactive use, @code{ar} prompts for
467 input (the prompt is @samp{AR >}), and continues executing even after
468 errors. If you redirect standard input to a script file, no prompts are
469 issued, and @code{ar} abandons execution (with a nonzero exit code)
472 The @code{ar} command language is @emph{not} designed to be equivalent
473 to the command-line options; in fact, it provides somewhat less control
474 over archives. The only purpose of the command language is to ease the
475 transition to @sc{gnu} @code{ar} for developers who already have scripts
476 written for the MRI ``librarian'' program.
478 The syntax for the @code{ar} command language is straightforward:
481 commands are recognized in upper or lower case; for example, @code{LIST}
482 is the same as @code{list}. In the following descriptions, commands are
483 shown in upper case for clarity.
486 a single command may appear on each line; it is the first word on the
490 empty lines are allowed, and have no effect.
493 comments are allowed; text after either of the characters @samp{*}
494 or @samp{;} is ignored.
497 Whenever you use a list of names as part of the argument to an @code{ar}
498 command, you can separate the individual names with either commas or
499 blanks. Commas are shown in the explanations below, for clarity.
502 @samp{+} is used as a line continuation character; if @samp{+} appears
503 at the end of a line, the text on the following line is considered part
504 of the current command.
507 Here are the commands you can use in @code{ar} scripts, or when using
508 @code{ar} interactively. Three of them have special significance:
510 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
511 a temporary file required for most of the other commands.
513 @code{SAVE} commits the changes so far specified by the script. Prior
514 to @code{SAVE}, commands affect only the temporary copy of the current
518 @item ADDLIB @var{archive}
519 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
520 Add all the contents of @var{archive} (or, if specified, each named
521 @var{module} from @var{archive}) to the current archive.
523 Requires prior use of @code{OPEN} or @code{CREATE}.
525 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
526 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
527 @c else like "ar q..."
528 Add each named @var{member} as a module in the current archive.
530 Requires prior use of @code{OPEN} or @code{CREATE}.
533 Discard the contents of the current archive, canceling the effect of
534 any operations since the last @code{SAVE}. May be executed (with no
535 effect) even if no current archive is specified.
537 @item CREATE @var{archive}
538 Creates an archive, and makes it the current archive (required for many
539 other commands). The new archive is created with a temporary name; it
540 is not actually saved as @var{archive} until you use @code{SAVE}.
541 You can overwrite existing archives; similarly, the contents of any
542 existing file named @var{archive} will not be destroyed until @code{SAVE}.
544 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
545 Delete each listed @var{module} from the current archive; equivalent to
546 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
548 Requires prior use of @code{OPEN} or @code{CREATE}.
550 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
551 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
552 List each named @var{module} present in @var{archive}. The separate
553 command @code{VERBOSE} specifies the form of the output: when verbose
554 output is off, output is like that of @samp{ar -t @var{archive}
555 @var{module}@dots{}}. When verbose output is on, the listing is like
556 @samp{ar -tv @var{archive} @var{module}@dots{}}.
558 Output normally goes to the standard output stream; however, if you
559 specify @var{outputfile} as a final argument, @code{ar} directs the
563 Exit from @code{ar}, with a @code{0} exit code to indicate successful
564 completion. This command does not save the output file; if you have
565 changed the current archive since the last @code{SAVE} command, those
568 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
569 Extract each named @var{module} from the current archive, writing them
570 into the current directory as separate files. Equivalent to @samp{ar -x
571 @var{archive} @var{module}@dots{}}.
573 Requires prior use of @code{OPEN} or @code{CREATE}.
576 @c FIXME Tokens but no commands???
583 Display full contents of the current archive, in ``verbose'' style
584 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
585 tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
586 enhancement, rather than present for MRI compatibility.)
588 Requires prior use of @code{OPEN} or @code{CREATE}.
590 @item OPEN @var{archive}
591 Opens an existing archive for use as the current archive (required for
592 many other commands). Any changes as the result of subsequent commands
593 will not actually affect @var{archive} until you next use @code{SAVE}.
595 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
596 In the current archive, replace each existing @var{module} (named in
597 the @code{REPLACE} arguments) from files in the current working directory.
598 To execute this command without errors, both the file, and the module in
599 the current archive, must exist.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 Toggle an internal flag governing the output from @code{DIRECTORY}.
605 When the flag is on, @code{DIRECTORY} output matches output from
606 @samp{ar -tv }@dots{}.
609 Commit your changes to the current archive, and actually save it as a
610 file with the name specified in the last @code{CREATE} or @code{OPEN}
613 Requires prior use of @code{OPEN} or @code{CREATE}.
622 The @sc{gnu} linker @code{ld} is now described in a separate manual.
623 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
632 nm [ -a | --debug-syms ] [ -g | --extern-only ]
633 [ -B ] [ -C | --demangle[=@var{style}] ] [ -D | --dynamic ]
634 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
635 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
636 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
637 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
638 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
639 [ --defined-only ] [-l | --line-numbers ]
640 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
643 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
644 If no object files are listed as arguments, @code{nm} assumes the file
647 For each symbol, @code{nm} shows:
651 The symbol value, in the radix selected by options (see below), or
652 hexadecimal by default.
655 The symbol type. At least the following types are used; others are, as
656 well, depending on the object file format. If lowercase, the symbol is
657 local; if uppercase, the symbol is global (external).
659 @c Some more detail on exactly what these symbol types are used for
663 The symbol's value is absolute, and will not be changed by further
667 The symbol is in the uninitialized data section (known as BSS).
670 The symbol is common. Common symbols are uninitialized data. When
671 linking, multiple common symbols may appear with the same name. If the
672 symbol is defined anywhere, the common symbols are treated as undefined
673 references. For more details on common symbols, see the discussion of
674 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
677 The symbol is in the initialized data section.
680 The symbol is in an initialized data section for small objects. Some
681 object file formats permit more efficient access to small data objects,
682 such as a global int variable as opposed to a large global array.
685 The symbol is an indirect reference to another symbol. This is a GNU
686 extension to the a.out object file format which is rarely used.
689 The symbol is a debugging symbol.
692 The symbol is in a read only data section.
695 The symbol is in an uninitialized data section for small objects.
698 The symbol is in the text (code) section.
701 The symbol is undefined.
704 The symbol is a weak object. When a weak defined symbol is linked with
705 a normal defined symbol, the normal defined symbol is used with no error.
706 When a weak undefined symbol is linked and the symbol is not defined,
707 the value of the weak symbol becomes zero with no error.
710 The symbol is a weak symbol that has not been specifically tagged as a
711 weak object symbol. When a weak defined symbol is linked with a normal
712 defined symbol, the normal defined symbol is used with no error.
713 When a weak undefined symbol is linked and the symbol is not defined,
714 the value of the weak symbol becomes zero with no error.
717 The symbol is a stabs symbol in an a.out object file. In this case, the
718 next values printed are the stabs other field, the stabs desc field, and
719 the stab type. Stabs symbols are used to hold debugging information;
720 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
721 ``stabs'' debug format}.
724 The symbol type is unknown, or object file format specific.
731 The long and short forms of options, shown here as alternatives, are
737 @itemx --print-file-name
738 @cindex input file name
740 @cindex source file name
741 Precede each symbol by the name of the input file (or archive member)
742 in which it was found, rather than identifying the input file once only,
743 before all of its symbols.
747 @cindex debugging symbols
748 Display all symbols, even debugger-only symbols; normally these are not
752 @cindex @code{nm} format
753 @cindex @code{nm} compatibility
754 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
757 @itemx --demangle[=@var{style}]
758 @cindex demangling in nm
759 Decode (@dfn{demangle}) low-level symbol names into user-level names.
760 Besides removing any initial underscore prepended by the system, this
761 makes C++ function names readable. Different compilers have different
762 mangling styles. The optional demangling style argument can be used to
763 choose an appropriate demangling style for your compiler. @xref{c++filt},
764 for more information on demangling.
767 Do not demangle low-level symbol names. This is the default.
771 @cindex dynamic symbols
772 Display the dynamic symbols rather than the normal symbols. This is
773 only meaningful for dynamic objects, such as certain types of shared
776 @item -f @var{format}
777 @itemx --format=@var{format}
778 @cindex @code{nm} format
779 @cindex @code{nm} compatibility
780 Use the output format @var{format}, which can be @code{bsd},
781 @code{sysv}, or @code{posix}. The default is @code{bsd}.
782 Only the first character of @var{format} is significant; it can be
783 either upper or lower case.
787 @cindex external symbols
788 Display only external symbols.
791 @itemx --line-numbers
792 @cindex symbol line numbers
793 For each symbol, use debugging information to try to find a filename and
794 line number. For a defined symbol, look for the line number of the
795 address of the symbol. For an undefined symbol, look for the line
796 number of a relocation entry which refers to the symbol. If line number
797 information can be found, print it after the other symbol information.
801 @itemx --numeric-sort
802 Sort symbols numerically by their addresses, rather than alphabetically
807 @cindex sorting symbols
808 Do not bother to sort the symbols in any order; print them in the order
813 Use the POSIX.2 standard output format instead of the default format.
814 Equivalent to @samp{-f posix}.
818 @cindex symbol index, listing
819 When listing symbols from archive members, include the index: a mapping
820 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
821 contain definitions for which names.
824 @itemx --reverse-sort
825 Reverse the order of the sort (whether numeric or alphabetic); let the
829 Sort symbols by size. The size is computed as the difference between
830 the value of the symbol and the value of the symbol with the next higher
831 value. The size of the symbol is printed, rather than the value.
834 @itemx --radix=@var{radix}
835 Use @var{radix} as the radix for printing the symbol values. It must be
836 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
838 @item --target=@var{bfdname}
839 @cindex object code format
840 Specify an object code format other than your system's default format.
841 @xref{Target Selection}, for more information.
844 @itemx --undefined-only
845 @cindex external symbols
846 @cindex undefined symbols
847 Display only undefined symbols (those external to each object file).
850 @cindex external symbols
851 @cindex undefined symbols
852 Display only defined symbols for each object file.
856 Show the version number of @code{nm} and exit.
859 Show a summary of the options to @code{nm} and exit.
866 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
867 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
868 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
869 [ -S | --strip-all ] [ -g | --strip-debug ]
870 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
871 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
872 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
873 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
874 [ -x | --discard-all ] [ -X | --discard-locals ]
875 [ -b @var{byte} | --byte=@var{byte} ]
876 [ -i @var{interleave} | --interleave=@var{interleave} ]
877 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
878 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
879 [ -p | --preserve-dates ] [ --debugging ]
880 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
881 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
882 [ --change-addresses=@var{incr} ]
883 [ --change-section-address @var{section}@{=,+,-@}@var{val} ]
884 [ --change-section-lma @var{section}@{=,+,-@}@var{val} ]
885 [ --change-section-vma @var{section}@{=,+,-@}@var{val} ]
886 [ --change-warnings ] [ --no-change-warnings ]
887 [ --set-section-flags @var{section}=@var{flags} ]
888 [ --add-section @var{sectionname}=@var{filename} ]
889 [ --change-leading-char ] [ --remove-leading-char ]
890 [ --redefine-sym @var{old}=@var{new} ] [ --weaken ]
891 [ -v | --verbose ] [ -V | --version ] [ --help ]
892 @var{infile} [@var{outfile}]
895 The @sc{gnu} @code{objcopy} utility copies the contents of an object
896 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
897 read and write the object files. It can write the destination object
898 file in a format different from that of the source object file. The
899 exact behavior of @code{objcopy} is controlled by command-line options.
900 Note that @code{objcopy} should be able to copy a fully linked file
901 between any two formats. However, copying a relocatable object file
902 between any two formats may not work as expected.
904 @code{objcopy} creates temporary files to do its translations and
905 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
906 translation work; it has access to all the formats described in @sc{bfd}
907 and thus is able to recognize most formats without being told
908 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
910 @code{objcopy} can be used to generate S-records by using an output
911 target of @samp{srec} (e.g., use @samp{-O srec}).
913 @code{objcopy} can be used to generate a raw binary file by using an
914 output target of @samp{binary} (e.g., use @samp{-O binary}). When
915 @code{objcopy} generates a raw binary file, it will essentially produce
916 a memory dump of the contents of the input object file. All symbols and
917 relocation information will be discarded. The memory dump will start at
918 the load address of the lowest section copied into the output file.
920 When generating an S-record or a raw binary file, it may be helpful to
921 use @samp{-S} to remove sections containing debugging information. In
922 some cases @samp{-R} will be useful to remove sections which contain
923 information that is not needed by the binary file.
928 The input and output files, respectively.
929 If you do not specify @var{outfile}, @code{objcopy} creates a
930 temporary file and destructively renames the result with
931 the name of @var{infile}.
933 @item -I @var{bfdname}
934 @itemx --input-target=@var{bfdname}
935 Consider the source file's object format to be @var{bfdname}, rather than
936 attempting to deduce it. @xref{Target Selection}, for more information.
938 @item -O @var{bfdname}
939 @itemx --output-target=@var{bfdname}
940 Write the output file using the object format @var{bfdname}.
941 @xref{Target Selection}, for more information.
943 @item -F @var{bfdname}
944 @itemx --target=@var{bfdname}
945 Use @var{bfdname} as the object format for both the input and the output
946 file; i.e., simply transfer data from source to destination with no
947 translation. @xref{Target Selection}, for more information.
949 @item -j @var{sectionname}
950 @itemx --only-section=@var{sectionname}
951 Copy only the named section from the input file to the output file.
952 This option may be given more than once. Note that using this option
953 inappropriately may make the output file unusable.
955 @item -R @var{sectionname}
956 @itemx --remove-section=@var{sectionname}
957 Remove any section named @var{sectionname} from the output file. This
958 option may be given more than once. Note that using this option
959 inappropriately may make the output file unusable.
963 Do not copy relocation and symbol information from the source file.
967 Do not copy debugging symbols from the source file.
969 @item --strip-unneeded
970 Strip all symbols that are not needed for relocation processing.
972 @item -K @var{symbolname}
973 @itemx --keep-symbol=@var{symbolname}
974 Copy only symbol @var{symbolname} from the source file. This option may
975 be given more than once.
977 @item -N @var{symbolname}
978 @itemx --strip-symbol=@var{symbolname}
979 Do not copy symbol @var{symbolname} from the source file. This option
980 may be given more than once.
982 @item -L @var{symbolname}
983 @itemx --localize-symbol=@var{symbolname}
984 Make symbol @var{symbolname} local to the file, so that it is not
985 visible externally. This option may be given more than once.
987 @item -W @var{symbolname}
988 @itemx --weaken-symbol=@var{symbolname}
989 Make symbol @var{symbolname} weak. This option may be given more than once.
993 Do not copy non-global symbols from the source file.
994 @c FIXME any reason to prefer "non-global" to "local" here?
997 @itemx --discard-locals
998 Do not copy compiler-generated local symbols.
999 (These usually start with @samp{L} or @samp{.}.)
1002 @itemx --byte=@var{byte}
1003 Keep only every @var{byte}th byte of the input file (header data is not
1004 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1005 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
1006 option, or the default of 4. This option is useful for creating files
1007 to program @sc{rom}. It is typically used with an @code{srec} output
1010 @item -i @var{interleave}
1011 @itemx --interleave=@var{interleave}
1012 Only copy one out of every @var{interleave} bytes. Select which byte to
1013 copy with the @var{-b} or @samp{--byte} option. The default is 4.
1014 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
1018 @itemx --preserve-dates
1019 Set the access and modification dates of the output file to be the same
1020 as those of the input file.
1023 Convert debugging information, if possible. This is not the default
1024 because only certain debugging formats are supported, and the
1025 conversion process can be time consuming.
1027 @item --gap-fill @var{val}
1028 Fill gaps between sections with @var{val}. This operation applies to
1029 the @emph{load address} (LMA) of the sections. It is done by increasing
1030 the size of the section with the lower address, and filling in the extra
1031 space created with @var{val}.
1033 @item --pad-to @var{address}
1034 Pad the output file up to the load address @var{address}. This is
1035 done by increasing the size of the last section. The extra space is
1036 filled in with the value specified by @samp{--gap-fill} (default zero).
1038 @item --set-start @var{val}
1039 Set the start address of the new file to @var{val}. Not all object file
1040 formats support setting the start address.
1042 @item --change-start @var{incr}
1043 @itemx --adjust-start @var{incr}
1044 @cindex changing start address
1045 Change the start address by adding @var{incr}. Not all object file
1046 formats support setting the start address.
1048 @item --change-addresses @var{incr}
1049 @itemx --adjust-vma @var{incr}
1050 @cindex changing object addresses
1051 Change the VMA and LMA addresses of all sections, as well as the start
1052 address, by adding @var{incr}. Some object file formats do not permit
1053 section addresses to be changed arbitrarily. Note that this does not
1054 relocate the sections; if the program expects sections to be loaded at a
1055 certain address, and this option is used to change the sections such
1056 that they are loaded at a different address, the program may fail.
1058 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1059 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1060 @cindex changing section address
1061 Set or change both the VMA address and the LMA address of the named
1062 @var{section}. If @samp{=} is used, the section address is set to
1063 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1064 section address. See the comments under @samp{--change-addresses},
1065 above. If @var{section} does not exist in the input file, a warning will
1066 be issued, unless @samp{--no-change-warnings} is used.
1068 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1069 @cindex changing section LMA
1070 Set or change the LMA address of the named @var{section}. The LMA
1071 address is the address where the section will be loaded into memory at
1072 program load time. Normally this is the same as the VMA address, which
1073 is the address of the section at program run time, but on some systems,
1074 especially those where a program is held in ROM, the two can be
1075 different. If @samp{=} is used, the section address is set to
1076 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1077 section address. See the comments under @samp{--change-addresses},
1078 above. If @var{section} does not exist in the input file, a warning
1079 will be issued, unless @samp{--no-change-warnings} is used.
1081 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1082 @cindex changing section VMA
1083 Set or change the VMA address of the named @var{section}. The VMA
1084 address is the address where the section will be located once the
1085 program has started executing. Normally this is the same as the LMA
1086 address, which is the address where the section will be loaded into
1087 memory, but on some systems, especially those where a program is held in
1088 ROM, the two can be different. If @samp{=} is used, the section address
1089 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1090 from the section address. See the comments under
1091 @samp{--change-addresses}, above. If @var{section} does not exist in
1092 the input file, a warning will be issued, unless
1093 @samp{--no-change-warnings} is used.
1095 @item --change-warnings
1096 @itemx --adjust-warnings
1097 If @samp{--change-section-address} or @samp{--change-section-lma} or
1098 @samp{--change-section-vma} is used, and the named section does not
1099 exist, issue a warning. This is the default.
1101 @item --no-change-warnings
1102 @itemx --no-adjust-warnings
1103 Do not issue a warning if @samp{--change-section-address} or
1104 @samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1105 if the named section does not exist.
1107 @item --set-section-flags @var{section}=@var{flags}
1108 Set the flags for the named section. The @var{flags} argument is a
1109 comma separated string of flag names. The recognized names are
1110 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1111 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1112 @samp{debug}. You can set the @samp{contents} flag for a section which
1113 does not have contents, but it is not meaningful to clear the
1114 @samp{contents} flag of a section which does have contents--just remove
1115 the section instead. Not all flags are meaningful for all object file
1118 @item --add-section @var{sectionname}=@var{filename}
1119 Add a new section named @var{sectionname} while copying the file. The
1120 contents of the new section are taken from the file @var{filename}. The
1121 size of the section will be the size of the file. This option only
1122 works on file formats which can support sections with arbitrary names.
1124 @item --change-leading-char
1125 Some object file formats use special characters at the start of
1126 symbols. The most common such character is underscore, which compilers
1127 often add before every symbol. This option tells @code{objcopy} to
1128 change the leading character of every symbol when it converts between
1129 object file formats. If the object file formats use the same leading
1130 character, this option has no effect. Otherwise, it will add a
1131 character, or remove a character, or change a character, as
1134 @item --remove-leading-char
1135 If the first character of a global symbol is a special symbol leading
1136 character used by the object file format, remove the character. The
1137 most common symbol leading character is underscore. This option will
1138 remove a leading underscore from all global symbols. This can be useful
1139 if you want to link together objects of different file formats with
1140 different conventions for symbol names. This is different from
1141 @code{--change-leading-char} because it always changes the symbol name
1142 when appropriate, regardless of the object file format of the output
1145 @item --redefine-sym @var{old}=@var{new}
1146 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1147 when one is trying link two things together for which you have no
1148 source, and there are name collisions.
1151 Change all global symbols in the file to be weak. This can be useful
1152 when building an object which will be linked against other objects using
1153 the @code{-R} option to the linker. This option is only effective when
1154 using an object file format which supports weak symbols.
1158 Show the version number of @code{objcopy}.
1162 Verbose output: list all object files modified. In the case of
1163 archives, @samp{objcopy -V} lists all members of the archive.
1166 Show a summary of the options to @code{objcopy}.
1172 @cindex object file information
1176 objdump [ -a | --archive-headers ]
1177 [ -b @var{bfdname} | --target=@var{bfdname} ]
1178 [ -C | --demangle[=@var{style}] ]
1179 [ -d | --disassemble ]
1180 [ -D | --disassemble-all ]
1181 [ -z | --disassemble-zeroes ]
1182 [ -EB | -EL | --endian=@{big | little @} ]
1183 [ -f | --file-headers ]
1184 [ --file-start-context ]
1185 [ -g | --debugging ]
1186 [ -h | --section-headers | --headers ]
1188 [ -j @var{section} | --section=@var{section} ]
1189 [ -l | --line-numbers ]
1191 [ -m @var{machine} | --architecture=@var{machine} ]
1192 [ -M @var{options} | --disassembler-options=@var{options}]
1193 [ -p | --private-headers ]
1195 [ -R | --dynamic-reloc ]
1196 [ -s | --full-contents ]
1199 [ -T | --dynamic-syms ]
1200 [ -x | --all-headers ]
1202 [ --start-address=@var{address} ]
1203 [ --stop-address=@var{address} ]
1204 [ --prefix-addresses]
1205 [ --[no-]show-raw-insn ]
1206 [ --adjust-vma=@var{offset} ]
1209 @var{objfile}@dots{}
1212 @code{objdump} displays information about one or more object files.
1213 The options control what particular information to display. This
1214 information is mostly useful to programmers who are working on the
1215 compilation tools, as opposed to programmers who just want their
1216 program to compile and work.
1218 @var{objfile}@dots{} are the object files to be examined. When you
1219 specify archives, @code{objdump} shows information on each of the member
1222 The long and short forms of options, shown here as alternatives, are
1223 equivalent. At least one option from the list
1224 @samp{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given.
1228 @itemx --archive-header
1229 @cindex archive headers
1230 If any of the @var{objfile} files are archives, display the archive
1231 header information (in a format similar to @samp{ls -l}). Besides the
1232 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1233 the object file format of each archive member.
1235 @item --adjust-vma=@var{offset}
1236 @cindex section addresses in objdump
1237 @cindex VMA in objdump
1238 When dumping information, first add @var{offset} to all the section
1239 addresses. This is useful if the section addresses do not correspond to
1240 the symbol table, which can happen when putting sections at particular
1241 addresses when using a format which can not represent section addresses,
1244 @item -b @var{bfdname}
1245 @itemx --target=@var{bfdname}
1246 @cindex object code format
1247 Specify that the object-code format for the object files is
1248 @var{bfdname}. This option may not be necessary; @var{objdump} can
1249 automatically recognize many formats.
1253 objdump -b oasys -m vax -h fu.o
1256 displays summary information from the section headers (@samp{-h}) of
1257 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1258 file in the format produced by Oasys compilers. You can list the
1259 formats available with the @samp{-i} option.
1260 @xref{Target Selection}, for more information.
1263 @itemx --demangle[=@var{style}]
1264 @cindex demangling in objdump
1265 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1266 Besides removing any initial underscore prepended by the system, this
1267 makes C++ function names readable. Different compilers have different
1268 mangling styles. The optional demangling style argument can be used to
1269 choose an appropriate demangling style for your compiler. @xref{c++filt},
1270 for more information on demangling.
1274 Display debugging information. This attempts to parse debugging
1275 information stored in the file and print it out using a C like syntax.
1276 Only certain types of debugging information have been implemented.
1279 @itemx --disassemble
1280 @cindex disassembling object code
1281 @cindex machine instructions
1282 Display the assembler mnemonics for the machine instructions from
1283 @var{objfile}. This option only disassembles those sections which are
1284 expected to contain instructions.
1287 @itemx --disassemble-all
1288 Like @samp{-d}, but disassemble the contents of all sections, not just
1289 those expected to contain instructions.
1291 @item --prefix-addresses
1292 When disassembling, print the complete address on each line. This is
1293 the older disassembly format.
1295 @item --disassemble-zeroes
1296 Normally the disassembly output will skip blocks of zeroes. This
1297 option directs the disassembler to disassemble those blocks, just like
1302 @itemx --endian=@{big|little@}
1304 @cindex disassembly endianness
1305 Specify the endianness of the object files. This only affects
1306 disassembly. This can be useful when disassembling a file format which
1307 does not describe endianness information, such as S-records.
1310 @itemx --file-header
1311 @cindex object file header
1312 Display summary information from the overall header of
1313 each of the @var{objfile} files.
1315 @item --file-start-context
1316 @cindex source code context
1317 Specify that when displaying interlisted source code/disassembly
1318 (assumes '-S') from a file that has not yet been displayed, extend the
1319 context to the start of the file.
1322 @itemx --section-header
1324 @cindex section headers
1325 Display summary information from the section headers of the
1328 File segments may be relocated to nonstandard addresses, for example by
1329 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1330 @code{ld}. However, some object file formats, such as a.out, do not
1331 store the starting address of the file segments. In those situations,
1332 although @code{ld} relocates the sections correctly, using @samp{objdump
1333 -h} to list the file section headers cannot show the correct addresses.
1334 Instead, it shows the usual addresses, which are implicit for the
1338 Print a summary of the options to @code{objdump} and exit.
1342 @cindex architectures available
1343 @cindex object formats available
1344 Display a list showing all architectures and object formats available
1345 for specification with @samp{-b} or @samp{-m}.
1348 @itemx --section=@var{name}
1349 @cindex section information
1350 Display information only for section @var{name}.
1353 @itemx --line-numbers
1354 @cindex source filenames for object files
1355 Label the display (using debugging information) with the filename and
1356 source line numbers corresponding to the object code or relocs shown.
1357 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1359 @item -m @var{machine}
1360 @itemx --architecture=@var{machine}
1361 @cindex architecture
1362 @cindex disassembly architecture
1363 Specify the architecture to use when disassembling object files. This
1364 can be useful when disassembling object files which do not describe
1365 architecture information, such as S-records. You can list the available
1366 architectures with the @samp{-i} option.
1368 @item -M @var{options}
1369 @itemx --disassembler-options=@var{options}
1370 Pass target specific information to the disassembler. Only supported on
1373 If the target is an ARM architecture then this switch can be used to
1374 select which register name set is used during disassembler. Specifying
1375 @samp{-M reg-name-std} (the default) will select the register names as
1376 used in ARM's instruction set documentation, but with register 13 called
1377 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1378 @samp{-M reg-names-apcs} will select the name set used by the ARM
1379 Procedure Call Standard, whilst specifying @samp{-M reg-names-raw} will
1380 just use @samp{r} followed by the register number.
1382 There are also two variants on the APCS register naming scheme enabled
1383 by @samp{-M reg-names-atpcs} and @samp{-M reg-names-special-atpcs} which
1384 use the ARM/Thumb Procedure Call Standard naming conventions. (Eiuther
1385 with the normal register name sor the special register names).
1387 This option can also be used for ARM architectures to force the
1388 disassembler to interpret all instructions as THUMB instructions by
1389 using the switch @samp{--disassembler-options=force-thumb}. This can be
1390 useful when attempting to disassemble thumb code produced by other
1394 @itemx --private-headers
1395 Print information that is specific to the object file format. The exact
1396 information printed depends upon the object file format. For some
1397 object file formats, no additional information is printed.
1401 @cindex relocation entries, in object file
1402 Print the relocation entries of the file. If used with @samp{-d} or
1403 @samp{-D}, the relocations are printed interspersed with the
1407 @itemx --dynamic-reloc
1408 @cindex dynamic relocation entries, in object file
1409 Print the dynamic relocation entries of the file. This is only
1410 meaningful for dynamic objects, such as certain types of shared
1414 @itemx --full-contents
1415 @cindex sections, full contents
1416 @cindex object file sections
1417 Display the full contents of any sections requested.
1421 @cindex source disassembly
1422 @cindex disassembly, with source
1423 Display source code intermixed with disassembly, if possible. Implies
1426 @item --show-raw-insn
1427 When disassembling instructions, print the instruction in hex as well as
1428 in symbolic form. This is the default except when
1429 @code{--prefix-addresses} is used.
1431 @item --no-show-raw-insn
1432 When disassembling instructions, do not print the instruction bytes.
1433 This is the default when @code{--prefix-addresses} is used.
1439 @cindex debug symbols
1440 @cindex ELF object file format
1441 Display the full contents of any sections requested. Display the
1442 contents of the .stab and .stab.index and .stab.excl sections from an
1443 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1444 @code{.stab} debugging symbol-table entries are carried in an ELF
1445 section. In most other file formats, debugging symbol-table entries are
1446 interleaved with linkage symbols, and are visible in the @samp{--syms}
1447 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1448 Overview,stabs.info, The ``stabs'' debug format}.
1450 @item --start-address=@var{address}
1451 @cindex start-address
1452 Start displaying data at the specified address. This affects the output
1453 of the @code{-d}, @code{-r} and @code{-s} options.
1455 @item --stop-address=@var{address}
1456 @cindex stop-address
1457 Stop displaying data at the specified address. This affects the output
1458 of the @code{-d}, @code{-r} and @code{-s} options.
1462 @cindex symbol table entries, printing
1463 Print the symbol table entries of the file.
1464 This is similar to the information provided by the @samp{nm} program.
1467 @itemx --dynamic-syms
1468 @cindex dynamic symbol table entries, printing
1469 Print the dynamic symbol table entries of the file. This is only
1470 meaningful for dynamic objects, such as certain types of shared
1471 libraries. This is similar to the information provided by the @samp{nm}
1472 program when given the @samp{-D} (@samp{--dynamic}) option.
1475 Print the version number of @code{objdump} and exit.
1479 @cindex all header information, object file
1480 @cindex header information, all
1481 Display all available header information, including the symbol table and
1482 relocation entries. Using @samp{-x} is equivalent to specifying all of
1483 @samp{-a -f -h -r -t}.
1487 @cindex wide output, printing
1488 Format some lines for output devices that have more than 80 columns.
1495 @cindex archive contents
1496 @cindex symbol index
1499 ranlib [-vV] @var{archive}
1502 @code{ranlib} generates an index to the contents of an archive and
1503 stores it in the archive. The index lists each symbol defined by a
1504 member of an archive that is a relocatable object file.
1506 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1508 An archive with such an index speeds up linking to the library and
1509 allows routines in the library to call each other without regard to
1510 their placement in the archive.
1512 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1513 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1520 Show the version number of @code{ranlib}.
1527 @cindex section sizes
1530 size [ -A | -B | --format=@var{compatibility} ]
1531 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1532 [ --target=@var{bfdname} ] [ -V | --version ]
1533 [ @var{objfile}@dots{} ]
1536 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1537 size---for each of the object or archive files @var{objfile} in its
1538 argument list. By default, one line of output is generated for each
1539 object file or each module in an archive.
1541 @var{objfile}@dots{} are the object files to be examined.
1542 If none are specified, the file @code{a.out} will be used.
1544 The command line options have the following meanings:
1549 @itemx --format=@var{compatibility}
1550 @cindex @code{size} display format
1551 Using one of these options, you can choose whether the output from @sc{gnu}
1552 @code{size} resembles output from System V @code{size} (using @samp{-A},
1553 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1554 @samp{--format=berkeley}). The default is the one-line format similar to
1556 @c Bonus for doc-source readers: you can also say --format=strange (or
1557 @c anything else that starts with 's') for sysv, and --format=boring (or
1558 @c anything else that starts with 'b') for Berkeley.
1560 Here is an example of the Berkeley (default) format of output from
1563 $ size --format=Berkeley ranlib size
1564 text data bss dec hex filename
1565 294880 81920 11592 388392 5ed28 ranlib
1566 294880 81920 11888 388688 5ee50 size
1570 This is the same data, but displayed closer to System V conventions:
1573 $ size --format=SysV ranlib size
1591 Show a summary of acceptable arguments and options.
1596 @itemx --radix=@var{number}
1597 @cindex @code{size} number format
1598 @cindex radix for section sizes
1599 Using one of these options, you can control whether the size of each
1600 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1601 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1602 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1603 values (8, 10, 16) are supported. The total size is always given in two
1604 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1605 octal and hexadecimal if you're using @samp{-o}.
1607 @item --target=@var{bfdname}
1608 @cindex object code format
1609 Specify that the object-code format for @var{objfile} is
1610 @var{bfdname}. This option may not be necessary; @code{size} can
1611 automatically recognize many formats.
1612 @xref{Target Selection}, for more information.
1616 Display the version number of @code{size}.
1622 @cindex listings strings
1623 @cindex printing strings
1624 @cindex strings, printing
1627 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1628 [--all] [--print-file-name] [--bytes=@var{min-len}]
1629 [--radix=@var{radix}] [--target=@var{bfdname}]
1630 [--help] [--version] @var{file}@dots{}
1633 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1634 character sequences that are at least 4 characters long (or the number
1635 given with the options below) and are followed by an unprintable
1636 character. By default, it only prints the strings from the initialized
1637 and loaded sections of object files; for other types of files, it prints
1638 the strings from the whole file.
1640 @code{strings} is mainly useful for determining the contents of non-text
1647 Do not scan only the initialized and loaded sections of object files;
1648 scan the whole files.
1651 @itemx --print-file-name
1652 Print the name of the file before each string.
1655 Print a summary of the program usage on the standard output and exit.
1657 @item -@var{min-len}
1658 @itemx -n @var{min-len}
1659 @itemx --bytes=@var{min-len}
1660 Print sequences of characters that are at least @var{min-len} characters
1661 long, instead of the default 4.
1664 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1665 act like @samp{-t d} instead. Since we can not be compatible with both
1666 ways, we simply chose one.
1668 @item -t @var{radix}
1669 @itemx --radix=@var{radix}
1670 Print the offset within the file before each string. The single
1671 character argument specifies the radix of the offset---@samp{o} for
1672 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1674 @item --target=@var{bfdname}
1675 @cindex object code format
1676 Specify an object code format other than your system's default format.
1677 @xref{Target Selection}, for more information.
1681 Print the program version number on the standard output and exit.
1688 @cindex removing symbols
1689 @cindex discarding symbols
1690 @cindex symbols, discarding
1693 strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1694 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1695 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1696 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1697 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1698 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1699 [ -x | --discard-all ] [ -X | --discard-locals ]
1700 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1701 [ -o @var{file} ] [ -p | --preserve-dates ]
1702 [ -v | --verbose ] [ -V | --version ] [ --help ]
1703 @var{objfile}@dots{}
1706 @sc{gnu} @code{strip} discards all symbols from object files
1707 @var{objfile}. The list of object files may include archives.
1708 At least one object file must be given.
1710 @code{strip} modifies the files named in its argument,
1711 rather than writing modified copies under different names.
1714 @item -F @var{bfdname}
1715 @itemx --target=@var{bfdname}
1716 Treat the original @var{objfile} as a file with the object
1717 code format @var{bfdname}, and rewrite it in the same format.
1718 @xref{Target Selection}, for more information.
1721 Show a summary of the options to @code{strip} and exit.
1723 @item -I @var{bfdname}
1724 @itemx --input-target=@var{bfdname}
1725 Treat the original @var{objfile} as a file with the object
1726 code format @var{bfdname}.
1727 @xref{Target Selection}, for more information.
1729 @item -O @var{bfdname}
1730 @itemx --output-target=@var{bfdname}
1731 Replace @var{objfile} with a file in the output format @var{bfdname}.
1732 @xref{Target Selection}, for more information.
1734 @item -R @var{sectionname}
1735 @itemx --remove-section=@var{sectionname}
1736 Remove any section named @var{sectionname} from the output file. This
1737 option may be given more than once. Note that using this option
1738 inappropriately may make the output file unusable.
1746 @itemx --strip-debug
1747 Remove debugging symbols only.
1749 @item --strip-unneeded
1750 Remove all symbols that are not needed for relocation processing.
1752 @item -K @var{symbolname}
1753 @itemx --keep-symbol=@var{symbolname}
1754 Keep only symbol @var{symbolname} from the source file. This option may
1755 be given more than once.
1757 @item -N @var{symbolname}
1758 @itemx --strip-symbol=@var{symbolname}
1759 Remove symbol @var{symbolname} from the source file. This option may be
1760 given more than once, and may be combined with strip options other than
1764 Put the stripped output in @var{file}, rather than replacing the
1765 existing file. When this argument is used, only one @var{objfile}
1766 argument may be specified.
1769 @itemx --preserve-dates
1770 Preserve the access and modification dates of the file.
1773 @itemx --discard-all
1774 Remove non-global symbols.
1777 @itemx --discard-locals
1778 Remove compiler-generated local symbols.
1779 (These usually start with @samp{L} or @samp{.}.)
1783 Show the version number for @code{strip}.
1787 Verbose output: list all object files modified. In the case of
1788 archives, @samp{strip -v} lists all members of the archive.
1791 @node c++filt, addr2line, strip, Top
1795 @cindex demangling C++ symbols
1798 c++filt [ -_ | --strip-underscores ]
1800 [ -n | --no-strip-underscores ]
1801 [ -s @var{format} | --format=@var{format} ]
1802 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1806 The C++ and Java languages provides function overloading, which means
1807 that you can write many functions with the same name (providing each
1808 takes parameters of different types). All C++ and Java function names
1809 are encoded into a low-level assembly label (this process is known as
1810 @dfn{mangling}). The @code{c++filt}
1811 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1812 MS-DOS this program is named @code{cxxfilt}.}
1813 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1814 names into user-level names so that the linker can keep these overloaded
1815 functions from clashing.
1817 Every alphanumeric word (consisting of letters, digits, underscores,
1818 dollars, or periods) seen in the input is a potential label. If the
1819 label decodes into a C++ name, the C++ name replaces the low-level
1822 You can use @code{c++filt} to decipher individual symbols:
1825 c++filt @var{symbol}
1828 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1829 names from the standard input and writes the demangled names to the
1830 standard output. All results are printed on the standard output.
1834 @itemx --strip-underscores
1835 On some systems, both the C and C++ compilers put an underscore in front
1836 of every name. For example, the C name @code{foo} gets the low-level
1837 name @code{_foo}. This option removes the initial underscore. Whether
1838 @code{c++filt} removes the underscore by default is target dependent.
1842 Prints demangled names using Java syntax. The default is to use C++
1846 @itemx --no-strip-underscores
1847 Do not remove the initial underscore.
1849 @item -s @var{format}
1850 @itemx --format=@var{format}
1851 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1852 different C++ compilers. The argument to this option selects which
1857 the one used by the @sc{gnu} compiler (the default method)
1859 the one used by the Lucid compiler
1861 the one specified by the C++ Annotated Reference Manual
1863 the one used by the HP compiler
1865 the one used by the EDG compiler
1867 the one used by the @sc{gnu} compiler with the new ABI.
1871 Print a summary of the options to @code{c++filt} and exit.
1874 Print the version number of @code{c++filt} and exit.
1878 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1879 user interface are subject to change in future releases. In particular,
1880 a command-line option may be required in the the future to decode a name
1881 passed as an argument on the command line; in other words,
1884 c++filt @var{symbol}
1888 may in a future release become
1891 c++filt @var{option} @var{symbol}
1899 @cindex address to file name and line number
1902 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1903 [ -C | --demangle[=@var{style} ]
1904 [ -e @var{filename} | --exe=@var{filename} ]
1905 [ -f | --functions ] [ -s | --basename ]
1906 [ -H | --help ] [ -V | --version ]
1910 @code{addr2line} translates program addresses into file names and line
1911 numbers. Given an address and an executable, it uses the debugging
1912 information in the executable to figure out which file name and line
1913 number are associated with a given address.
1915 The executable to use is specified with the @code{-e} option. The
1916 default is the file @file{a.out}.
1918 @code{addr2line} has two modes of operation.
1920 In the first, hexadecimal addresses are specified on the command line,
1921 and @code{addr2line} displays the file name and line number for each
1924 In the second, @code{addr2line} reads hexadecimal addresses from
1925 standard input, and prints the file name and line number for each
1926 address on standard output. In this mode, @code{addr2line} may be used
1927 in a pipe to convert dynamically chosen addresses.
1929 The format of the output is @samp{FILENAME:LINENO}. The file name and
1930 line number for each address is printed on a separate line. If the
1931 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1932 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1933 containing the address.
1935 If the file name or function name can not be determined,
1936 @code{addr2line} will print two question marks in their place. If the
1937 line number can not be determined, @code{addr2line} will print 0.
1939 The long and short forms of options, shown here as alternatives, are
1943 @item -b @var{bfdname}
1944 @itemx --target=@var{bfdname}
1945 @cindex object code format
1946 Specify that the object-code format for the object files is
1950 @itemx --demangle[=@var{style}]
1951 @cindex demangling in objdump
1952 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1953 Besides removing any initial underscore prepended by the system, this
1954 makes C++ function names readable. Different compilers have different
1955 mangling styles. The optional demangling style argument can be used to
1956 choose an appropriate demangling style for your compiler. @xref{c++filt},
1957 for more information on demangling.
1959 @item -e @var{filename}
1960 @itemx --exe=@var{filename}
1961 Specify the name of the executable for which addresses should be
1962 translated. The default file is @file{a.out}.
1966 Display function names as well as file and line number information.
1970 Display only the base of each file name.
1975 @code{nlmconv} converts a relocatable object file into a NetWare
1979 @code{nlmconv} currently works with @samp{i386} object
1980 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1981 object files in @sc{elf}, or @code{a.out} format@footnote{
1982 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1983 format in the Binary File Descriptor library. It has only been tested
1984 with the above formats.}.
1988 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1989 utilities, since it is only useful for NLM targets.
1993 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1994 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1995 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1996 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1997 [ -h | --help ] [ -V | --version ]
1998 @var{infile} @var{outfile}
2001 @code{nlmconv} converts the relocatable @samp{i386} object file
2002 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2003 reading @var{headerfile} for NLM header information. For instructions
2004 on writing the NLM command file language used in header files, see the
2005 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2006 Development and Tools Overview}, which is part of the NLM Software
2007 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2008 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2009 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
2012 @code{nlmconv} can perform a link step. In other words, you can list
2013 more than one object file for input if you list them in the definitions
2014 file (rather than simply specifying one input file on the command line).
2015 In this case, @code{nlmconv} calls the linker for you.
2018 @item -I @var{bfdname}
2019 @itemx --input-target=@var{bfdname}
2020 Object format of the input file. @code{nlmconv} can usually determine
2021 the format of a given file (so no default is necessary).
2022 @xref{Target Selection}, for more information.
2024 @item -O @var{bfdname}
2025 @itemx --output-target=@var{bfdname}
2026 Object format of the output file. @code{nlmconv} infers the output
2027 format based on the input format, e.g. for a @samp{i386} input file the
2028 output format is @samp{nlm32-i386}.
2029 @xref{Target Selection}, for more information.
2031 @item -T @var{headerfile}
2032 @itemx --header-file=@var{headerfile}
2033 Reads @var{headerfile} for NLM header information. For instructions on
2034 writing the NLM command file language used in header files, see@ see the
2035 @samp{linkers} section, of the @cite{NLM Development and Tools
2036 Overview}, which is part of the NLM Software Developer's Kit, available
2041 Displays (on standard error) the linker command line used by @code{nlmconv}.
2043 @item -l @var{linker}
2044 @itemx --linker=@var{linker}
2045 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2050 Prints a usage summary.
2054 Prints the version number for @code{nlmconv}.
2060 @code{windres} may be used to manipulate Windows resources.
2063 @emph{Warning:} @code{windres} is not always built as part of the binary
2064 utilities, since it is only useful for Windows targets.
2068 windres [options] [input-file] [output-file]
2071 @code{windres} reads resources from an input file and copies them into
2072 an output file. Either file may be in one of three formats:
2076 A text format read by the Resource Compiler.
2079 A binary format generated by the Resource Compiler.
2082 A COFF object or executable.
2085 The exact description of these different formats is available in
2086 documentation from Microsoft.
2088 When @code{windres} converts from the @code{rc} format to the @code{res}
2089 format, it is acting like the Windows Resource Compiler. When
2090 @code{windres} converts from the @code{res} format to the @code{coff}
2091 format, it is acting like the Windows @code{CVTRES} program.
2093 When @code{windres} generates an @code{rc} file, the output is similar
2094 but not identical to the format expected for the input. When an input
2095 @code{rc} file refers to an external filename, an output @code{rc} file
2096 will instead include the file contents.
2098 If the input or output format is not specified, @code{windres} will
2099 guess based on the file name, or, for the input file, the file contents.
2100 A file with an extension of @file{.rc} will be treated as an @code{rc}
2101 file, a file with an extension of @file{.res} will be treated as a
2102 @code{res} file, and a file with an extension of @file{.o} or
2103 @file{.exe} will be treated as a @code{coff} file.
2105 If no output file is specified, @code{windres} will print the resources
2106 in @code{rc} format to standard output.
2108 The normal use is for you to write an @code{rc} file, use @code{windres}
2109 to convert it to a COFF object file, and then link the COFF file into
2110 your application. This will make the resources described in the
2111 @code{rc} file available to Windows.
2114 @item -i @var{filename}
2115 @itemx --input @var{filename}
2116 The name of the input file. If this option is not used, then
2117 @code{windres} will use the first non-option argument as the input file
2118 name. If there are no non-option arguments, then @code{windres} will
2119 read from standard input. @code{windres} can not read a COFF file from
2122 @item -o @var{filename}
2123 @itemx --output @var{filename}
2124 The name of the output file. If this option is not used, then
2125 @code{windres} will use the first non-option argument, after any used
2126 for the input file name, as the output file name. If there is no
2127 non-option argument, then @code{windres} will write to standard output.
2128 @code{windres} can not write a COFF file to standard output.
2130 @item -I @var{format}
2131 @itemx --input-format @var{format}
2132 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2133 @samp{coff}. If no input format is specified, @code{windres} will
2134 guess, as described above.
2136 @item -O @var{format}
2137 @itemx --output-format @var{format}
2138 The output format to generate. @var{format} may be @samp{res},
2139 @samp{rc}, or @samp{coff}. If no output format is specified,
2140 @code{windres} will guess, as described above.
2142 @item -F @var{target}
2143 @itemx --target @var{target}
2144 Specify the BFD format to use for a COFF file as input or output. This
2145 is a BFD target name; you can use the @code{--help} option to see a list
2146 of supported targets. Normally @code{windres} will use the default
2147 format, which is the first one listed by the @code{--help} option.
2148 @ref{Target Selection}.
2150 @item --preprocessor @var{program}
2151 When @code{windres} reads an @code{rc} file, it runs it through the C
2152 preprocessor first. This option may be used to specify the preprocessor
2153 to use, including any leading arguments. The default preprocessor
2154 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2156 @item --include-dir @var{directory}
2157 Specify an include directory to use when reading an @code{rc} file.
2158 @code{windres} will pass this to the preprocessor as an @code{-I}
2159 option. @code{windres} will also search this directory when looking for
2160 files named in the @code{rc} file.
2162 @item -D @var{target}
2163 @itemx --define @var{sym}[=@var{val}]
2164 Specify a @code{-D} option to pass to the preprocessor when reading an
2168 Enable verbose mode. This tells you what the preprocessor is if you
2171 @item --language @var{val}
2172 Specify the default language to use when reading an @code{rc} file.
2173 @var{val} should be a hexadecimal language code. The low eight bits are
2174 the language, and the high eight bits are the sublanguage.
2176 @item --use-temp-file
2177 Use a temporary file to instead of using popen to read the output of
2178 the preprocessor. Use this option if the popen implementation is buggy
2179 on the host (eg., certain non-English language versions of Windows 95 and
2180 Windows 98 are known to have buggy popen where the output will instead
2183 @item --no-use-temp-file
2184 Use popen, not a temporary file, to read the output of the preprocessor.
2185 This is the default behaviour.
2188 Prints a usage summary.
2191 Prints the version number for @code{windres}.
2194 If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2195 this will turn on parser debugging.
2200 @chapter Create files needed to build and use DLLs
2204 @code{dlltool} may be used to create the files needed to build and use
2205 dynamic link libraries (DLLs).
2208 @emph{Warning:} @code{dlltool} is not always built as part of the binary
2209 utilities, since it is only useful for those targets which support DLLs.
2213 dlltool [-d|--input-def @var{def-file-name}]
2214 [-b|--base-file @var{base-file-name}]
2215 [-e|--output-exp @var{exports-file-name}]
2216 [-z|--output-def @var{def-file-name}]
2217 [-l|--output-lib @var{library-file-name}]
2218 [--export-all-symbols] [--no-export-all-symbols]
2219 [--exclude-symbols @var{list}]
2220 [--no-default-excludes]
2221 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2222 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2223 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2224 [-A|--add-stdcall-alias]
2225 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2226 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2227 [object-file @dots{}]
2230 @code{dlltool} reads its inputs, which can come from the @samp{-d} and
2231 @samp{-b} options as well as object files specified on the command
2232 line. It then processes these inputs and if the @samp{-e} option has
2233 been specified it creates a exports file. If the @samp{-l} option
2234 has been specified it creates a library file and if the @samp{-z} option
2235 has been specified it creates a def file. Any or all of the -e, -l
2236 and -z options can be present in one invocation of dlltool.
2238 When creating a DLL, along with the source for the DLL, it is necessary
2239 to have three other files. @code{dlltool} can help with the creation of
2242 The first file is a @samp{.def} file which specifies which functions are
2243 exported from the DLL, which functions the DLL imports, and so on. This
2244 is a text file and can be created by hand, or @code{dlltool} can be used
2245 to create it using the @samp{-z} option. In this case @code{dlltool}
2246 will scan the object files specified on its command line looking for
2247 those functions which have been specially marked as being exported and
2248 put entries for them in the .def file it creates.
2250 In order to mark a function as being exported from a DLL, it needs to
2251 have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2252 section of the object file. This can be done in C by using the
2256 asm (".section .drectve");
2257 asm (".ascii \"-export:my_func\"");
2259 int my_func (void) @{ @dots{} @}
2262 The second file needed for DLL creation is an exports file. This file
2263 is linked with the object files that make up the body of the DLL and it
2264 handles the interface between the DLL and the outside world. This is a
2265 binary file and it can be created by giving the @samp{-e} option to
2266 @code{dlltool} when it is creating or reading in a .def file.
2268 The third file needed for DLL creation is the library file that programs
2269 will link with in order to access the functions in the DLL. This file
2270 can be created by giving the @samp{-l} option to dlltool when it
2271 is creating or reading in a .def file.
2273 @code{dlltool} builds the library file by hand, but it builds the
2274 exports file by creating temporary files containing assembler statements
2275 and then assembling these. The @samp{-S} command line option can be
2276 used to specify the path to the assembler that dlltool will use,
2277 and the @samp{-f} option can be used to pass specific flags to that
2278 assembler. The @samp{-n} can be used to prevent dlltool from deleting
2279 these temporary assembler files when it is done, and if @samp{-n} is
2280 specified twice then this will prevent dlltool from deleting the
2281 temporary object files it used to build the library.
2283 Here is an example of creating a DLL from a source file @samp{dll.c} and
2284 also creating a program (from an object file called @samp{program.o})
2289 dlltool -e exports.o -l dll.lib dll.o
2290 gcc dll.o exports.o -o dll.dll
2291 gcc program.o dll.lib -o program
2294 The command line options have the following meanings:
2298 @item -d @var{filename}
2299 @itemx --input-def @var{filename}
2300 @cindex input .def file
2301 Specifies the name of a .def file to be read in and processed.
2303 @item -b @var{filename}
2304 @itemx --base-file @var{filename}
2306 Specifies the name of a base file to be read in and processed. The
2307 contents of this file will be added to the relocation section in the
2308 exports file generated by dlltool.
2310 @item -e @var{filename}
2311 @itemx --output-exp @var{filename}
2312 Specifies the name of the export file to be created by dlltool.
2314 @item -z @var{filename}
2315 @itemx --output-def @var{filename}
2316 Specifies the name of the .def file to be created by dlltool.
2318 @item -l @var{filename}
2319 @itemx --output-lib @var{filename}
2320 Specifies the name of the library file to be created by dlltool.
2322 @item --export-all-symbols
2323 Treat all global and weak defined symbols found in the input object
2324 files as symbols to be exported. There is a small list of symbols which
2325 are not exported by default; see the @code{--no-default-excludes}
2326 option. You may add to the list of symbols to not export by using the
2327 @code{--exclude-symbols} option.
2329 @item --no-export-all-symbols
2330 Only export symbols explicitly listed in an input .def file or in
2331 @samp{.drectve} sections in the input object files. This is the default
2332 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2333 attributes in the source code.
2335 @item --exclude-symbols @var{list}
2336 Do not export the symbols in @var{list}. This is a list of symbol names
2337 separated by comma or colon characters. The symbol names should not
2338 contain a leading underscore. This is only meaningful when
2339 @code{--export-all-symbols} is used.
2341 @item --no-default-excludes
2342 When @code{--export-all-symbols} is used, it will by default avoid
2343 exporting certain special symbols. The current list of symbols to avoid
2344 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2345 @samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2346 to go ahead and export these special symbols. This is only meaningful
2347 when @code{--export-all-symbols} is used.
2350 @itemx --as @var{path}
2351 Specifies the path, including the filename, of the assembler to be used
2352 to create the exports file.
2354 @item -f @var{switches}
2355 @itemx --as-flags @var{switches}
2356 Specifies any specific command line switches to be passed to the
2357 assembler when building the exports file. This option will work even if
2358 the @samp{-S} option is not used. This option only takes one argument,
2359 and if it occurs more than once on the command line, then later
2360 occurrences will override earlier occurrences. So if it is necessary to
2361 pass multiple switches to the assembler they should be enclosed in
2365 @itemx --dll-name @var{name}
2366 Specifies the name to be stored in the .def file as the name of the DLL
2367 when the @samp{-e} option is used. If this option is not present, then
2368 the filename given to the @samp{-e} option will be used as the name of
2371 @item -m @var{machine}
2372 @itemx -machine @var{machine}
2373 Specifies the type of machine for which the library file should be
2374 built. @code{dlltool} has a built in default type, depending upon how
2375 it was created, but this option can be used to override that. This is
2376 normally only useful when creating DLLs for an ARM processor, when the
2377 contents of the DLL are actually encode using THUMB instructions.
2380 @itemx --add-indirect
2381 Specifies that when @code{dlltool} is creating the exports file it
2382 should add a section which allows the exported functions to be
2383 referenced without using the import library. Whatever the hell that
2387 @itemx --add-underscore
2388 Specifies that when @code{dlltool} is creating the exports file it
2389 should prepend an underscore to the names of the exported functions.
2393 Specifies that when @code{dlltool} is creating the exports file it
2394 should not append the string @samp{@@ <number>}. These numbers are
2395 called ordinal numbers and they represent another way of accessing the
2396 function in a DLL, other than by name.
2399 @itemx --add-stdcall-alias
2400 Specifies that when @code{dlltool} is creating the exports file it
2401 should add aliases for stdcall symbols without @samp{@@ <number>}
2402 in addition to the symbols with @samp{@@ <number>}.
2406 Specifies that when @code{dlltool} is creating the exports and library
2407 files it should omit the .idata4 section. This is for compatibility
2408 with certain operating systems.
2412 Specifies that when @code{dlltool} is creating the exports and library
2413 files it should omit the .idata5 section. This is for compatibility
2414 with certain operating systems.
2418 Specifies that @code{dlltool} should mark the objects in the library
2419 file and exports file that it produces as supporting interworking
2420 between ARM and THUMB code.
2424 Makes @code{dlltool} preserve the temporary assembler files it used to
2425 create the exports file. If this option is repeated then dlltool will
2426 also preserve the temporary object files it uses to create the library
2431 Make dlltool describe what it is doing.
2435 Displays a list of command line options and then exits.
2439 Displays dlltool's version number and then exits.
2446 @cindex ELF file information
2450 readelf [ -a | --all ]
2451 [ -h | --file-header]
2452 [ -l | --program-headers | --segments]
2453 [ -S | --section-headers | --sections]
2455 [ -s | --syms | --symbols]
2459 [ -V | --version-info]
2460 [ -D | --use-dynamic]
2461 [ -x <number> | --hex-dump=<number>]
2462 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2466 @var{elffile}@dots{}
2469 @code{readelf} displays information about one or more ELF format object
2470 files. The options control what particular information to display.
2472 @var{elffile}@dots{} are the object files to be examined. At the
2473 moment, @code{readelf} does not support examining archives, nor does it
2474 support examing 64 bit ELF files.
2476 The long and short forms of options, shown here as alternatives, are
2477 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2483 Equivalent to specifiying @samp{--file-header},
2484 @samp{--program-headers}, @samp{--sections}, @samp{--symbols},
2485 @samp{--relocs}, @samp{--dynamic}, @samp{--notes} and
2486 @samp{--version-info}.
2489 @itemx --file-header
2490 @cindex ELF file header information
2491 Displays the information contained in the ELF header at the start of the
2495 @itemx --program-headers
2497 @cindex ELF program header information
2498 @cindex ELF segment information
2499 Displays the information contained in the file's segment headers, if it
2504 @itemx --section-headers
2505 @cindex ELF section information
2506 Displays the information contained in the file's section headers, if it
2512 @cindex ELF symbol table information
2513 Displays the entries in symbol table section of the file, if it has one.
2517 Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2521 @cindex ELF core notes
2522 Displays the contents of the NOTE segment, if it exists.
2526 @cindex ELF reloc information
2527 Displays the contents of the file's relocation section, if it ha one.
2531 @cindex ELF dynamic section information
2532 Displays the contents of the file's dynamic section, if it has one.
2535 @itemx --version-info
2536 @cindex ELF version sections informations
2537 Displays the contents of the version sections in the file, it they
2541 @itemx --use-dynamic
2542 When displaying symbols, this option makes @code{readelf} use the
2543 symbol table in the file's dynamic section, rather than the one in the
2547 @itemx --hex-dump=<number>
2548 Displays the contents of the indicated section as a hexadecimal dump.
2551 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2552 Displays the contents of the debug sections in the file, if any are
2553 present. If one of the optional letters or words follows the switch
2554 then only data found in those specific sections will be dumped.
2557 Display a histogram of bucket list lengths when displaying the contents
2558 of the symbol tables.
2562 Display the version number of readelf.
2566 Display the command line options understood by @code{readelf}.
2571 @node Selecting The Target System
2572 @chapter Selecting the target system
2574 You can specify three aspects of the target system to the @sc{gnu}
2575 binary file utilities, each in several ways:
2585 the linker emulation (which applies to the linker only)
2588 In the following summaries, the lists of ways to specify values are in
2589 order of decreasing precedence. The ways listed first override those
2592 The commands to list valid values only list the values for which the
2593 programs you are running were configured. If they were configured with
2594 @samp{--enable-targets=all}, the commands list most of the available
2595 values, but a few are left out; not all targets can be configured in at
2596 once because some of them can only be configured @dfn{native} (on hosts
2597 with the same type as the target system).
2600 * Target Selection::
2601 * Architecture Selection::
2602 * Linker Emulation Selection::
2605 @node Target Selection
2606 @section Target Selection
2608 A @dfn{target} is an object file format. A given target may be
2609 supported for multiple architectures (@pxref{Architecture Selection}).
2610 A target selection may also have variations for different operating
2611 systems or architectures.
2613 The command to list valid target values is @samp{objdump -i}
2614 (the first column of output contains the relevant information).
2616 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2617 @samp{a.out-sunos-big}.
2619 You can also specify a target using a configuration triplet. This is
2620 the same sort of name that is passed to @file{configure} to specify a
2621 target. When you use a configuration triplet as an argument, it must be
2622 fully canonicalized. You can see the canonical version of a triplet by
2623 running the shell script @file{config.sub} which is included with the
2626 Some sample configuration triplets are: @samp{m68k-hp-bsd},
2627 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2629 @subheading @code{objdump} Target
2635 command line option: @samp{-b} or @samp{--target}
2638 environment variable @code{GNUTARGET}
2641 deduced from the input file
2644 @subheading @code{objcopy} and @code{strip} Input Target
2650 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2653 environment variable @code{GNUTARGET}
2656 deduced from the input file
2659 @subheading @code{objcopy} and @code{strip} Output Target
2665 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2668 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2671 environment variable @code{GNUTARGET}
2674 deduced from the input file
2677 @subheading @code{nm}, @code{size}, and @code{strings} Target
2683 command line option: @samp{--target}
2686 environment variable @code{GNUTARGET}
2689 deduced from the input file
2692 @subheading Linker Input Target
2698 command line option: @samp{-b} or @samp{--format}
2699 (@pxref{Options,,Options,ld.info,Using LD})
2702 script command @code{TARGET}
2703 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2706 environment variable @code{GNUTARGET}
2707 (@pxref{Environment,,Environment,ld.info,Using LD})
2710 the default target of the selected linker emulation
2711 (@pxref{Linker Emulation Selection})
2714 @subheading Linker Output Target
2720 command line option: @samp{-oformat}
2721 (@pxref{Options,,Options,ld.info,Using LD})
2724 script command @code{OUTPUT_FORMAT}
2725 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2728 the linker input target (see ``Linker Input Target'' above)
2731 @node Architecture Selection
2732 @section Architecture selection
2734 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2735 to run. Its name may contain a colon, separating the name of the
2736 processor family from the name of the particular @sc{cpu}.
2738 The command to list valid architecture values is @samp{objdump -i} (the
2739 second column contains the relevant information).
2741 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2743 @subheading @code{objdump} Architecture
2749 command line option: @samp{-m} or @samp{--architecture}
2752 deduced from the input file
2755 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2761 deduced from the input file
2764 @subheading Linker Input Architecture
2770 deduced from the input file
2773 @subheading Linker Output Architecture
2779 script command @code{OUTPUT_ARCH}
2780 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2783 the default architecture from the linker output target
2784 (@pxref{Target Selection})
2787 @node Linker Emulation Selection
2788 @section Linker emulation selection
2790 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2791 the linker default values for the other aspects of the target system.
2792 In particular, it consists of
2802 several ``hook'' functions that are run at certain stages of the linking
2803 process to do special things that some targets require
2806 The command to list valid linker emulation values is @samp{ld -V}.
2808 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2814 command line option: @samp{-m}
2815 (@pxref{Options,,Options,ld.info,Using LD})
2818 environment variable @code{LDEMULATION}
2821 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2822 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2825 @node Reporting Bugs
2826 @chapter Reporting Bugs
2828 @cindex reporting bugs
2830 Your bug reports play an essential role in making the binary utilities
2833 Reporting a bug may help you by bringing a solution to your problem, or
2834 it may not. But in any case the principal function of a bug report is
2835 to help the entire community by making the next version of the binary
2836 utilities work better. Bug reports are your contribution to their
2839 In order for a bug report to serve its purpose, you must include the
2840 information that enables us to fix the bug.
2843 * Bug Criteria:: Have you found a bug?
2844 * Bug Reporting:: How to report bugs
2848 @section Have you found a bug?
2849 @cindex bug criteria
2851 If you are not sure whether you have found a bug, here are some guidelines:
2854 @cindex fatal signal
2857 If a binary utility gets a fatal signal, for any input whatever, that is
2858 a bug. Reliable utilities never crash.
2860 @cindex error on valid input
2862 If a binary utility produces an error message for valid input, that is a
2866 If you are an experienced user of binary utilities, your suggestions for
2867 improvement are welcome in any case.
2871 @section How to report bugs
2873 @cindex bugs, reporting
2875 A number of companies and individuals offer support for @sc{gnu}
2876 products. If you obtained the binary utilities from a support
2877 organization, we recommend you contact that organization first.
2879 You can find contact information for many support companies and
2880 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2883 In any event, we also recommend that you send bug reports for the binary
2884 utilities to @samp{bug-gnu-utils@@gnu.org}.
2886 The fundamental principle of reporting bugs usefully is this:
2887 @strong{report all the facts}. If you are not sure whether to state a
2888 fact or leave it out, state it!
2890 Often people omit facts because they think they know what causes the
2891 problem and assume that some details do not matter. Thus, you might
2892 assume that the name of a file you use in an example does not matter.
2893 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2894 a stray memory reference which happens to fetch from the location where
2895 that pathname is stored in memory; perhaps, if the pathname were
2896 different, the contents of that location would fool the utility into
2897 doing the right thing despite the bug. Play it safe and give a
2898 specific, complete example. That is the easiest thing for you to do,
2899 and the most helpful.
2901 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2902 it is new to us. Therefore, always write your bug reports on the assumption
2903 that the bug has not been reported previously.
2905 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2906 bell?'' Those bug reports are useless, and we urge everyone to
2907 @emph{refuse to respond to them} except to chide the sender to report
2910 To enable us to fix the bug, you should include all these things:
2914 The version of the utility. Each utility announces it if you start it
2915 with the @samp{--version} argument.
2917 Without this, we will not know whether there is any point in looking for
2918 the bug in the current version of the binary utilities.
2921 Any patches you may have applied to the source, including any patches
2922 made to the @code{BFD} library.
2925 The type of machine you are using, and the operating system name and
2929 What compiler (and its version) was used to compile the utilities---e.g.
2933 The command arguments you gave the utility to observe the bug. To
2934 guarantee you will not omit something important, list them all. A copy
2935 of the Makefile (or the output from make) is sufficient.
2937 If we were to try to guess the arguments, we would probably guess wrong
2938 and then we might not encounter the bug.
2941 A complete input file, or set of input files, that will reproduce the
2942 bug. If the utility is reading an object file or files, then it is
2943 generally most helpful to send the actual object files, uuencoded if
2944 necessary to get them through the mail system. Note that
2945 @samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2946 sending very large files to it. Making the files available for
2947 anonymous FTP is OK.
2949 If the source files were produced exclusively using @sc{gnu} programs
2950 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2951 may be OK to send the source files rather than the object files. In
2952 this case, be sure to say exactly what version of @code{gcc}, or
2953 whatever, was used to produce the object files. Also say how
2954 @code{gcc}, or whatever, was configured.
2957 A description of what behavior you observe that you believe is
2958 incorrect. For example, ``It gets a fatal signal.''
2960 Of course, if the bug is that the utility gets a fatal signal, then we
2961 will certainly notice it. But if the bug is incorrect output, we might
2962 not notice unless it is glaringly wrong. You might as well not give us
2963 a chance to make a mistake.
2965 Even if the problem you experience is a fatal signal, you should still
2966 say so explicitly. Suppose something strange is going on, such as your
2967 copy of the utility is out of synch, or you have encountered a bug in
2968 the C library on your system. (This has happened!) Your copy might
2969 crash and ours would not. If you told us to expect a crash, then when
2970 ours fails to crash, we would know that the bug was not happening for
2971 us. If you had not told us to expect a crash, then we would not be able
2972 to draw any conclusion from our observations.
2975 If you wish to suggest changes to the source, send us context diffs, as
2976 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2977 option. Always send diffs from the old file to the new file. If you
2978 wish to discuss something in the @code{ld} source, refer to it by
2979 context, not by line number.
2981 The line numbers in our development sources will not match those in your
2982 sources. Your line numbers would convey no useful information to us.
2985 Here are some things that are not necessary:
2989 A description of the envelope of the bug.
2991 Often people who encounter a bug spend a lot of time investigating
2992 which changes to the input file will make the bug go away and which
2993 changes will not affect it.
2995 This is often time consuming and not very useful, because the way we
2996 will find the bug is by running a single example under the debugger
2997 with breakpoints, not by pure deduction from a series of examples.
2998 We recommend that you save your time for something else.
3000 Of course, if you can find a simpler example to report @emph{instead}
3001 of the original one, that is a convenience for us. Errors in the
3002 output will be easier to spot, running under the debugger will take
3003 less time, and so on.
3005 However, simplification is not vital; if you do not want to do this,
3006 report the bug anyway and send us the entire test case you used.
3009 A patch for the bug.
3011 A patch for the bug does help us if it is a good one. But do not omit
3012 the necessary information, such as the test case, on the assumption that
3013 a patch is all we need. We might see problems with your patch and decide
3014 to fix the problem another way, or we might not understand it at all.
3016 Sometimes with programs as complicated as the binary utilities it is
3017 very hard to construct an example that will make the program follow a
3018 certain path through the code. If you do not send us the example, we
3019 will not be able to construct one, so we will not be able to verify that
3022 And if we cannot understand what bug you are trying to fix, or why your
3023 patch should be an improvement, we will not install it. A test case will
3024 help us to understand.
3027 A guess about what the bug is or what it depends on.
3029 Such guesses are usually wrong. Even we cannot guess right about such
3030 things without first using the debugger to find the facts.