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NAME

       ar - create, modify, and extract from archives

SYNOPSIS

       ar [--plugin name] [-X32_64] [-]p[mod [relpos] [count]] archive
       [member...]

DESCRIPTION

       The GNU ar program creates, modifies, and extracts from archives.  An
       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 members of the archive).

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

       GNU ar can maintain archives whose members have names of any length;
       however, depending on how 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).

       ar is considered a binary utility because archives of this sort are
       most often used as libraries holding commonly needed subroutines.

       ar creates an index to the symbols defined in relocatable object
       modules in the archive when you specify the modifier s.  Once created,
       this index is updated in the archive whenever ar makes a change to its
       contents (save for the 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 nm -s or nm --print-armap to list this index table.  If an
       archive lacks the table, another form of ar called ranlib can be used
       to add just the table.

       GNU ar can optionally create a thin archive, which contains a symbol
       index and references to the original copies of the member files of the
       archives.  Such an archive is useful for building libraries for use
       within a local build, where the relocatable objects are expected to
       remain available, and copying the contents of each object would only
       waste time and space.  Thin archives are also flattened, so that adding
       one or more archives to a thin archive will add the elements of the
       nested archive individually.  The paths to the elements of the archive
       are stored relative to the archive itself.

       GNU ar is designed to be compatible with two different facilities.  You
       can control its activity using command-line options, like the different
       varieties of ar on Unix systems; or, if you specify the single command-
       line option -M, you can control it with a script supplied via standard
       input, like the MRI "librarian" program.

OPTIONS

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

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

       The p keyletter specifies what operation to execute; it may be any of
       the following, but you must specify only one of them:

       d   Delete modules from the archive.  Specify the names of modules to
           be deleted as member...; the archive is untouched if you specify no
           files to delete.

           If you specify the v modifier, ar lists each module as it is
           deleted.

       m   Use this operation to 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 "m", any members you name in the
           member arguments are moved to the end of the archive; you can use
           the a, b, or i modifiers to move them to a specified place instead.

       p   Print the specified members of the archive, to the standard output
           file.  If the v modifier is specified, show the member name before
           copying its contents to standard output.

           If you specify no member arguments, all the files in the archive
           are printed.

       q   Quick append; Historically, add the files member... to the end of
           archive, without checking for replacement.

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

           The modifier v makes 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
           ar s or ranlib explicitly to update the symbol table index.

           However, too many different systems assume quick append rebuilds
           the index, so GNU ar implements q as a synonym for r.

       r   Insert the files member... into archive (with replacement). This
           operation differs from q in that any previously existing members
           are deleted if their names match those being added.

           If one of the files named in member... does not exist, 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 a, b, or i to request placement
           relative to some existing member.

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

       t   Display a table listing the contents of archive, or those of the
           files listed in member... 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 v modifier.

           If you do not specify a member, all files in the archive are
           listed.

           If there is more than one file with the same name (say, fie) in an
           archive (say b.a), ar t b.a fie lists only the first instance; to
           see them all, you must ask for a complete listing---in our example,
           ar t b.a.

       x   Extract members (named member) from the archive.  You can use the v
           modifier with this operation, to request that ar list each name as
           it extracts it.

           If you do not specify a member, all files in the archive are
           extracted.

           Files cannot be extracted from a thin archive.

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

       a   Add new files after an existing member of the archive.  If you use
           the modifier a, the name of an existing archive member must be
           present as the relpos argument, before the archive specification.

       b   Add new files before an existing member of the archive.  If you use
           the modifier b, the name of an existing archive member must be
           present as the relpos argument, before the archive specification.
           (same as i).

       c   Create the archive.  The specified archive is always created if it
           did not 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.

       D   Operate in deterministic mode.  When adding files and the archive
           index use zero for UIDs, GIDs, timestamps, and use consistent file
           modes for all files.  When this option is used, if ar is used with
           identical options and identical input files, multiple runs will
           create identical output files regardless of the input files'
           owners, groups, file modes, or modification times.

       f   Truncate names in the archive.  GNU ar will normally permit file
           names of any length.  This will cause it to create archives which
           are not compatible with the native ar program on some systems.  If
           this is a concern, the f modifier may be used to truncate file
           names when putting them in the archive.

       i   Insert new files before an existing member of the archive.  If you
           use the modifier i, the name of an existing archive member must be
           present as the relpos argument, before the archive specification.
           (same as b).

       l   This modifier is accepted but not used.

       N   Uses the count parameter.  This is used if there are multiple
           entries in the archive with the same name.  Extract or delete
           instance count of the given name from the archive.

       o   Preserve the original dates of members when extracting them.  If
           you do not specify this modifier, files extracted from the archive
           are stamped with the time of extraction.

       P   Use the full path name when matching names in the archive.  GNU ar
           can not create an archive with a full path name (such archives are
           not POSIX complaint), but other archive creators can.  This option
           will cause GNU ar to match file names using a complete path name,
           which can be convenient when extracting a single file from an
           archive created by another tool.

       s   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 ar
           s on an archive is equivalent to running ranlib on it.

       S   Do not generate an archive symbol table.  This can speed up
           building a large library in several steps.  The resulting archive
           can not be used with the linker.  In order to build a symbol table,
           you must omit the S modifier on the last execution of ar, or you
           must run ranlib on the archive.

       T   Make the specified archive a thin archive.  If it already exists
           and is a regular archive, the existing members must be present in
           the same directory as archive.

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

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

       V   This modifier shows the version number of ar.

       ar ignores an initial option spelt -X32_64, for compatibility with AIX.
       The behaviour produced by this option is the default for GNU ar.  ar
       does not support any of the other -X options; in particular, it does
       not support -X32 which is the default for AIX ar.

       The optional command line switch --plugin name causes ar to load the
       plugin called name which adds support for more file formats.  This
       option is only available if the toolchain has been built with plugin
       support enabled.

       @file
           Read command-line options from file.  The options read are inserted
           in place of the original @file option.  If file does not exist, or
           cannot be read, then the option will be treated literally, and not
           removed.

           Options in file are separated by whitespace.  A whitespace
           character may be included in an option by surrounding the entire
           option in either single or double quotes.  Any character (including
           a backslash) may be included by prefixing the character to be
           included with a backslash.  The file may itself contain additional
           @file options; any such options will be processed recursively.

SEE ALSO

       nm(1), ranlib(1), and the Info entries for binutils.

COPYRIGHT

       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free
       Software Foundation, Inc.

       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is included in the section entitled "GNU
       Free Documentation License".