Add OBJF_SYMS flag and use it to decide whether or not we have already

[deliverable/binutils-gdb.git] / binutils / binutils.texinfo

\input texinfo
@setfilename binutils.info
@synindex ky cp
@c
@c This file documents the GNU binary utilities "ar", "ld", "objdump", "nm", 
@c "size", "strip", and "ranlib".
@c
@c Copyright (C) 1991 Free Software Foundation, Inc.
@c 
@c This text may be freely distributed under the terms of the GNU
@c General Public License.
@c
@c $Id$
@iftex
@finalout
@c @smallbook
@end iftex
@c @cropmarks
@setchapternewpage odd
@settitle GNU Binary Utilities
@titlepage
@title The GNU Binary Utilities
@subtitle Version 1.90
@sp 1
@subtitle October 1991
@author Roland H. Pesch
@author Cygnus Support
@page

@tex
\def\$#1${{#1}} % Kluge: collect RCS revision info without $...$
\xdef\manvers{\$Revision$} % For use in headers, footers too
{\parskip=0pt \hfill Cygnus Support\par \hfill \manvers\par \hfill
\TeX{}info \texinfoversion\par }
@end tex

@vskip 0pt plus 1filll
Copyright @copyright{} 1991 Free Software Foundation, Inc.

Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
are preserved on all copies.

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided also that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Permission is granted to copy and distribute translations of this manual
into another language, under the above conditions for modified versions.
@end titlepage

@node Top, ar, (dir), (dir)
@chapter Introduction

@cindex version
This brief manual contains preliminary documentation for the GNU binary
utilities (collectively version 1.90): 
@table @code
@item ar
Create, modify, and extract from archives

@item nm
List symbols from object files

@item objdump
Display information from object files

@item ranlib
Generate index to archive contents

@item size
List section sizes and total size

@item strip
Discard symbols
@end table

@ifinfo
Copyright @copyright{} 1991 Free Software Foundation, Inc.

Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
are preserved on all copies.

@ignore
Permission is granted to process this file through TeX and print the
results, provided the printed document carries a copying permission
notice identical to this one except for the removal of this paragraph
(this paragraph not being relevant to the printed manual).

@end ignore

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided also that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Permission is granted to copy and distribute translations of this manual
into another language, under the above conditions for modified versions.
@end ifinfo

@menu
* ar::                          Create, modify, and extract from archives
* ld::                          See ld.info
* nm::                          List symbols from object files
* objdump::                     Display information from object files
* ranlib::                      Generate index to archive contents
* size::                        List section sizes and total size
* strip::                       Discard symbols
* Index::
@end menu

@node ar, ld, Top, Top
@chapter ar

@kindex ar
@cindex archives
@cindex collections of files
@smallexample
  ar [-]@var{p}@var{mod} [ @var{membername} ] @var{archive} @var{files}@dots{}
@end smallexample

The GNU @code{ar} program creates, modifies, and extracts from
archives.  An @dfn{archive} is a single file holding a collection of
other files in a structure that makes it possible to retrieve
the original individual files (called @dfn{members} of the archive).

The original files' contents, mode (permissions), timestamp, owner, and
group are preserved in the archive, and may be reconstituted on
extraction.  

@cindex name length
GNU @code{ar} can maintain archives whose members have names of any
length; however, depending on how @code{ar} is configured on your
system, a limit on member-name length may be imposed (for compatibility
with archive formats maintained with other tools).  If it exists, the
limit is often 15 characters (typical of formats related to a.out) or 16
characters (typical of formats related to coff).

@cindex libraries
@code{ar} is considered a binary utility because archives of this sort
are most often used as @dfn{libraries} holding commonly needed
subroutines.

@cindex symbol index
@code{ar} will create an index to the symbols defined in relocatable
object modules in the archive when you specify the modifier @samp{s}.
Once created, this index is updated in the archive whenever @code{ar}
makes a change to its contents (save for the @samp{q} update operation).
An archive with such an index speeds up linking to the library, and
allows routines in the library to call each other without regard to
their placement in the archive.

You may use @samp{nm -s} or @samp{nm +print-armap} to list this index
table.  If an archive lacks the table, another form of @code{ar} called
@code{ranlib} can be used to add just the table.

@code{ar} insists on at least two arguments to execute: one
keyletter specifying the @emph{operation} (optionally accompanied by other
keyletters specifying @emph{modifiers}), and the archive name to act on.

Most operations can also accept further @var{files} arguments,
specifying particular files to operate on.

GNU @code{ar} allows you to mix the operation code @var{p} and modifier
flags @var{mod} in any order, within the first command-line argument.

If you wish, you may begin the first command-line argument with a
dash.

@cindex operations on archive
The @var{p} keyletter specifies what operation to execute; it may be
any of the following, but you must specify only one of them:

@table @code
@item d
@cindex deleting from archive
@emph{Delete} modules from the archive.  Specify the names of modules to
be deleted as @var{files}; the archive is untouched if you
specify no files to delete.

If you specify the @samp{v} modifier, @code{ar} will list each module
as it is deleted.

@item m
@cindex moving in archive
Use this operation to @emph{move} members in an archive.

The ordering of members in an archive can make a difference in how
programs are linked using the library, if a symbol is defined in more
than one member.  

If no modifiers are used with @code{m}, any members you name in the
@var{files} arguments are moved to the @emph{end} of the archive;
you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
specified place instead.

@item p
@cindex printing from archive
@emph{Print} the specified members of the archive, to the standard
output file.  If the @samp{v} modifier is specified, show the member
name before copying its contents to standard output.

If you specify no @var{files}, all the files in the archive are printed.

@item q
@cindex quick append to archive
@emph{Quick append}; add @var{files} to the end of @var{archive},
without checking for replacement.  

The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
operation; new members are always placed at the end of the archive.

The modifier @samp{v} makes @code{ar} list each file as it is appended.

Since the point of this operation is speed, the archive's symbol table
index is not updated, even if it already existed; you can use @samp{ar s} or
@code{ranlib} explicitly to update the symbol table index.

@item r
@cindex replacement in archive
Insert @var{files} into @var{archive} (with @emph{replacement}). This
operation differs from @samp{q} in that any previously existing members
are deleted if their names match those being added.

If one of the files named in @var{files} doesn't exist, @code{ar}
displays an error message, and leaves undisturbed any existing members
of the archive matching that name.

By default, new members are added at the end of the file; but you may
use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
placement relative to some existing member.

The modifier @samp{v} used with this operation elicits a line of
output for each file inserted, along with one of the letters @samp{a} or
@samp{r} to indicate whether the file was appended (no old member
deleted) or replaced.

@item t
@cindex contents of archive
Display a @emph{table} listing the contents of @var{archive}, or those
of the files listed in @var{files} that are present in the
archive.  Normally only the member name is shown; if you also want to
see the modes (permissions), timestamp, owner, group, and size, you can
request that by also specifying the @samp{v} modifier.

If you do not specify any @var{files}, all files in the archive
are listed.

@cindex repeated names in archive
@cindex name duplication in archive
If there is more than one file with the same name (say, @samp{fie}) in
an archive (say @samp{b.a}), @samp{ar t b.a fie} will list only the
first instance; to see them all, you must ask for a complete
listing---in our example, @samp{ar t b.a}.
@c WRS only; per Gumby, this is implementation-dependent, and in a more
@c recent case in fact works the other way.

@item x
@cindex extract from archive
@emph{Extract} members (named @var{files}) from the archive.  You can
use the @samp{v} modifier with this operation, to request that
@code{ar} list each name as it extracts it.

If you do not specify any @var{files}, all files in the archive
are extracted.

@end table

A number of modifiers (@var{mod}) may immediately follow the @var{p}
keyletter, to specify variations on an operation's behavior:

@table @code
@item a
@cindex relative placement in archive
Add new files @emph{after} an existing member of the
archive.  If you use the modifier @code{a}, the name of an existing archive
member must be present as the @var{membername} argument, before the
@var{archive} specification.

@item b
Add new files @emph{before} an existing member of the
archive.  If you use the modifier @code{b}, the name of an existing archive
member must be present as the @var{membername} argument, before the
@var{archive} specification.  (same as @samp{i}).

@item c
@cindex creating archives
@emph{Create} the archive.  The specified @var{archive} is always
created if it didn't exist, when you request an update.  But a warning is
issued unless you specify in advance that you expect to create it, by
using this modifier.

@item i
Insert new files @emph{before} an existing member of the
archive.  If you use the modifier @code{i}, the name of an existing archive
member must be present as the @var{membername} argument, before the
@var{archive} specification.  (same as @samp{b}).

@item l
This modifier is accepted but not used.
@c whaffor ar l modifier??? presumably compat; with
@c what???---pesch@@cygnus.com, 25jan91 

@item o
@cindex dates in archive
Preserve the @emph{original} dates of members when extracting them.  If
you do not specify this modifier, files extracted from the archive
will be stamped with the time of extraction.

@item s
@cindex writing archive index
Write an object-file index into the archive, or update an existing one,
even if no other change is made to the archive.  You may use this modifier
flag either with any operation, or alone.  Running @samp{ar s} on an
archive is equivalent to running @samp{ranlib} on it.

@item u
@cindex updating an archive
Normally, @code{ar r}@dots{} inserts all files
listed into the archive.  If you would like to insert @emph{only} those
of the files you list that are newer than existing members of the same
names, use this modifier.  The @samp{u} modifier is allowed only for the
operation @samp{r} (replace).  In particular, the combination @samp{qu} is
not allowed, since checking the timestamps would lose any speed
advantage from the operation @samp{q}.

@item v
This modifier requests the @emph{verbose} version of an operation.  Many
operations display additional information, such as filenames processed,
when the modifier @samp{v} is appended.

@end table

@node ld, nm, ar, Top
@chapter ld
@cindex linker
@kindex ld
The GNU linker @code{ld} is now described in a separate manual.
@xref{Top,, Overview,, GLD: the GNU linker}.

@node nm, objdump, ld, Top
@chapter nm
@cindex symbols
@kindex nm

@smallexample
  nm [ -a | +debug-syms ]  [ -g | +extern-only ]
      [ -s | +print-armap ]  [ -o | +print-file-name ]  
      [ -n | +numeric-sort ]  [ -p | +no-sort ]
      [ -r | +reverse-sort ]  [ -u | +undefined-only ]  
      [ +target @var{bfdname} ]
      [ @var{objfiles}@dots{} ]
@end smallexample

GNU @code{nm} will list the symbols from object files @var{objfiles}.

The long and short forms of options, shown here as alternatives, are
equivalent.

@table @code
@item @var{objfiles}@dots{}
@kindex a.out
Object files whose symbols are to be listed.  If no object files are
listed as arguments, @code{nm} assumes @samp{a.out}.

@item -a
@itemx +debug-syms 
@cindex debugging symbols
Display debugger-only symbols; normally these are not listed.

@item -g
@itemx +extern-only 
@cindex external symbols
Display only external symbols.

@item -p
@itemx +no-sort 
@cindex sorting symbols
Don't bother to sort the symbols in any order; just print them in the
order encountered.

@item -n
@itemx +numeric-sort 
Sort symbols numerically by their addresses, not alphabetically by their
names. 

@item -s
@itemx +print-armap
@cindex symbol index, listing
When listing symbols from archive members, include the index: a mapping
(stored in the archive by @code{ar} or @code{ranlib}) of what modules
contain definitions for what names.

@item -o
@itemx +print-file-name 
@cindex input file name
@cindex file name
@cindex source file name
Precede each symbol by the name of the input file where it was found,
rather than identifying the input file once only before all of its
symbols. 

@item -r
@itemx +reverse-sort 
Reverse the sense of the sort (whether numeric or alphabetic); let the
last come first.

@item +target @var{bfdname}
@c @item +target
@cindex object code format
Specify an object code format other than your system's default format.
@xref{objdump}, for information on listing available formats.
@c FIXME what *does* +target/no arg do?

@item -u
@itemx +undefined-only 
@cindex external symbols
@cindex undefined symbols
Display only undefined symbols (those external to each object file).

@end table

@node objdump, ranlib, nm, Top
@chapter objdump

@cindex object file information
@kindex objdump

@smallexample
  objdump [ -a ]  [ -b @var{bfdname} ]  [ -d ]  [ -f ]
          [ -h | +header ]  [ -i ]  [ -j @var{section} ]  [ -l ]
          [ -m @var{machine} ]  [ -r | +reloc ]  [ -s ]
          [ -t | +syms ]  [ -x ]
          @var{objfiles}@dots{}
@end smallexample

@code{objdump} displays information about one or more object files.
The options control what particular information to display.  This
information is mostly useful to programmers who are working on the
compilation tools, as opposed to programmers who just want their
program to compile and work.

The long and short forms of options, shown here as alternatives, are
equivalent.

@table @code
@item @var{objfiles}@dots{}
The object files to be examined.  When you specify archives,
@code{objdump} shows information on each of the member object files.

@item -a
@c print_arelt_descr
@cindex archive headers
If any files from @var{objfiles} are archives, display the archive
header information (in a format similar to @samp{ls -l}).  Besides the
information you could list with @samp{ar tv}, @samp{objdump -a} shows
the object file format of each archive member.

@c suggest longname +target or +format or +bfd
@item -b @var{bfdname}
@cindex object code format
You can specify a particular object-code format for your object files as
@var{bfdname}.  This may not be necessary; @var{objdump} can
automatically recognize many formats.  For example,
@example
objdump -b oasys -m vax -h fu.o
@end example
@noindent
Displays summary information from the section headers (@samp{-h}) of
@file{fu.o}, which is explicitly identified (@samp{-m}) as a Vax object
file in the format produced by Oasys compilers.  You can list the
formats available with the @samp{-i} option.

@item -d
@cindex disassembling object code
@cindex machine instructions
Disassemble.  Display the assembler mnemonics for the machine
instructions from @var{objfiles}.

@item -f
@cindex object file header
File header.  Display summary information from the overall header of
each file in @var{objfiles}.

@item -h
@itemx +header
@cindex section headers
Header.  Display summary information from the section headers of the
object file.

@item -i
@cindex architectures available
@cindex object formats available
Display a list showing all architectures and object formats available
for specification with @code{-b} or @code{-m}.

@c suggest longname +section
@item -j @var{name}
@cindex section information
Display information only for section @var{name}

@c suggest longname +label or +linespec
@item -l
@cindex source filenames for object files
Label the display (using debugging information) with the source filename
and line numbers corresponding to the object code shown.

@c suggest longname +architecture
@item -m @var{machine}
@cindex architecture
Specify the object files @var{objfiles} are for architecture
@var{machine}.  You can list available architectures using the @samp{-i}
option. 

@item -r
@itemx +reloc
@cindex relocation entries, in object file
Relocation.  Print the relocation entries of the file.

@item -s
@cindex sections, full contents
@cindex object file sections
Display the full contents of any sections requested.

@item -t
@itemx +syms
@cindex symbol table entries, printing
Symbol Table.  Print the symbol table entries of the file.
This is similar to the information provided by the @samp{nm} program.

@item -x
@cindex all header information, object file
@cindex header information, all
Display all available header information, including the symbol table and
relocation entries.  Using @samp{-x} is equivalent to specifying all of
@samp{-a -f -h -r -t}.

@end table

@node ranlib, size, objdump, Top
@chapter ranlib

@kindex ranlib
@cindex archive contents
@cindex symbol index

@smallexample
  ranlib @var{archive}
@end smallexample

@code{ranlib} generates an index to the contents of an archive, and
stores it in the archive.  The index lists each symbol defined by a
member of an archive that is a relocatable object file.  

You may use @samp{nm -s} or @samp{nm +print-armap} to list this index.

An archive with such an index speeds up linking to the library, and
allows routines in the library to call each other without regard to
their placement in the archive.

The GNU @code{ranlib} program is another form of GNU @code{ar}; running
@code{ranlib} is completely equivalent to executing @samp{ar -s}.
@xref{ar}.

@node size, strip, ranlib, Top
@chapter size

@kindex size
@cindex section sizes

@smallexample
  size [ -A | -B | +format @var{compatibility} ]
       [ +help ]  [ -d | -o | -x | +radix @var{number} ]
       [ +target @var{bfdname} ]  [ -V | +version ]  
       @var{objfiles}@dots{}
@end smallexample

The GNU @code{size} utility lists the section sizes---and the total
size---for each of the object files @var{objfiles} in its argument list.
By default, one line of output is generated for each object file or each
module in an archive.

The command line options have the following meanings:
@table @code
@item @var{objfiles}@dots{}
The object files to be examined.

@item -A
@itemx -B
@itemx +format @var{compatibility}
@cindex size display format
Using one of these options, you can choose whether the output from GNU
@code{size} resembles output from System V @code{size} (using @samp{-A},
or @samp{+format sysv}), or Berkeley @code{size} (using @samp{-B}, or
@samp{+format berkeley}).  The default is the one-line format similar to
Berkeley's.  
@c Bonus for doc-source readers: you can also say +format=strange (or
@c anything else that starts with 's') for sysv, and +format=boring (or
@c anything else that starts with 'b') for Berkeley.

Here is an example of the Berkeley (default) format of output from
@code{size}: 
@smallexample
 eg$  size +format Berkeley ranlib size
text    data    bss     dec     hex     filename
294880  81920   11592   388392  5ed28   ranlib
294880  81920   11888   388688  5ee50   size
@end smallexample

@noindent
This is the same data, but displayed closer to System V conventions:

@smallexample
 eg$  size +format SysV ranlib size
ranlib  :
section         size         addr
.text         294880         8192       
.data          81920       303104       
.bss           11592       385024       
Total         388392    


size  :
section         size         addr
.text         294880         8192       
.data          81920       303104       
.bss           11888       385024       
Total         388688    
@end smallexample

@item +help
Show a summary of acceptable arguments and options.

@item -d
@itemx -o
@itemx -x
@itemx +radix @var{number}
@cindex size number format
@cindex radix for section sizes
Using one of these options, you can control whether the size of each
section is given in decimal (@samp{-d}, or @samp{+radix 10}); octal
(@samp{-o}, or @samp{+radix 8}); or hexadecimal (@samp{-x}, or
@samp{+radix 16}).  In @samp{+radix @var{number}}, only the three
values (8, 10, 16) are supported.  The total size is always given in two
radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
octal and hexadecimal if you're using @samp{-o}.

@item +target @var{bfdname}
@cindex object code format
You can specify a particular object-code format for @var{objfiles} as
@var{bfdname}.  This may not be necessary; @var{size} can
automatically recognize many formats.  @xref{objdump}, for information
on listing available formats.

@item -V
@itemx +version
Display version number information on @code{size} itself.

@end table

@node strip, Index, size, Top
@chapter strip

@kindex strip
@cindex removing symbols
@cindex discarding symbols

@smallexample
  strip [ -s | +strip-all ]  [ -g | -S | +strip-debug ]
         [ -x | +discard-all ]  [ -X | +discard-locals ]
         [ -T @var{bfdname} ]
         @var{objfiles}@dots{}
@end smallexample

GNU @code{strip} will discard all symbols from object files
@var{objfiles}, if no options are specified; or only certain symbols,
depending on its command-line options.

@code{strip} will not execute unless at least one object file is listed.

@quotation
@emph{WARNING:} @code{strip} modifies the files named in its argument,
rather than writing modified copies under different names.
@end quotation

The long and short forms of options, shown here as alternatives, are
equivalent.

@table @code
@item -s
@itemx +strip-all 
@cindex all symbols, discarding
This is the default case: strip all symbol entries from @var{objfiles}.

@item -g
@itemx -S
@itemx +strip-debug 
@cindex debugging symbols, discarding
Discard only debugging symbol information from @var{objfiles}.

@item -x
@itemx +discard-all 
@cindex local symbols, discarding
Discard all symbols local to each file in @var{objfiles}.
@emph{WARNING:} Note that @code{+discard-all} discards only @emph{local}
symbols, in spite of its name.

@item -X
@itemx +discard-locals 
Discard local symbols starting with @samp{L} from each file in
@var{objfiles}.  (Some compilers produce internally-used symbols that
begin with @samp{L}.)

@item -T @var{bfdname}
@cindex object code format
You can specify a particular object-code format @var{bfdname} for
@var{objfiles}.  This may not be necessary; @var{strip} can automatically
recognize many formats.  @xref{objdump}, for information on listing
available formats.
@end table

@node Index, , strip, Top
@unnumbered Index

@printindex cp

@contents
@bye