ar [-]{dmpqrtx}[abcilosSuvV] [membername] archivefiles...
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 may be reconstituted 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 will create 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.
ar insists on at least two arguments to execute: one
keyletter specifying the operation (optionally accompanied by other
keyletters specifying modifiers), and the archive name to act on.
Most operations can also accept further files arguments,
specifying particular files to operate on.
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 files; the archive is untouched if you
specify no files to delete.
If you specify the `v' modifier, ar will list 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
files 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 files, all the files in the archive are printed.
q
Quick append; add files 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 files 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 files doesn't 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 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 `v' modifier.
If you do not specify any files, 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' will list 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 files) 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 any files, all files in the archive
are extracted.
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 membername 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 membername argument, before the
archive specification. (same as `i').
c
Create the archive. The specified 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.
f
Truncate names in the archive.
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 membername argument, before the
archive specification. (same as `b').
l
This modifier is accepted but not used.
o
Preserve the 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.
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.
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.
SEE ALSO
`binutils'
entry in
info;
The GNU Binary Utilities, Roland H. Pesch (October 1991).
nm(1),
ranlib(1).
COPYING
Copyright (c) 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 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, except that this permission notice may be included in
translations approved by the Free Software Foundation instead of in
the original English.