NAME

ar - maintain portable archive or library

SYNOPSIS

ar [ --V ] -- key [ arg ] [ posname ] afile [ name. . . ]

DESCRIPTION

The ar command maintains groups of files combined into a single archive file. Its main use is to create and update library files. However, it can be used for any similar purpose. The magic string and the file headers used by ar consist of printable ASCII characters. If an archive is composed of printable files, the entire archive is printable.

When ar creates an archive, it creates headers in a format that is portable across all machines. The portable archive format and structure are described in detail in ar(4). The archive symbol table (described in ar(4)) is used by the link editor ld to effect multiple passes over libraries of object files in an efficient manner. An archive symbol table is only created and maintained by ar when there is at least one object file in the archive. The archive symbol table is in a specially named file that is always the first file in the archive. This file is never mentioned or accessible to the user. Whenever the ar command is used to create or update the contents of such an archive, the symbol table is rebuilt. The s option described below will force the symbol table to be rebuilt.

OPTIONS

-V

ar prints its version number on standard error.

Unlike command options, the key is a required part of the ar command line. The key is formed with one of the following letters: drqtpmx. Arguments to the key, alternatively, are made with one or more of the following set: vuaibcs. posname is an archive member name used as a reference point in positioning other files in the archive. afile is the archive file. The names are constituent files in the archive file. The meanings of the key characters are as follows:

d

Delete the named files from the archive file.

r

Replace the named files in the archive file. If the optional character u is used with r, then only those files with dates of modification later than the archive files are replaced. If an optional positioning character from the set abi is used, then the posname argument must be present and specifies that new files are to be placed after (a )or before (b or i) posname. Otherwise new files are placed at the end.

q

Quickly append the named files to the end of the archive file. Optional positioning characters are invalid. The command does not check whether the added members are already in the archive. This option is useful to avoid quadratic behavior when creating a large archive piece-by-piece.

t

Print a table of contents of the archive file. If no names are given, all files in the archive are listed. If names are given, only those files are listed.

p

Print the named files in the archive.

m

Move the named files to the end of the archive. If a positioning character is present, then the posname argument must be present and, as in r, specifies where the files are to be moved.

x

Extract the named files. If no names are given, all files in the archive are extracted. In neither case does x alter the archive file.

The meanings of the other key arguments are as follows:

v

Give a verbose file-by-file description of the making of a new archive file from the old archive and the constituent files. When used with t, give a long listing of all information about the files. When used with x ,print the filename preceding each extraction.

c

Suppress the message that is produced by default when afile is created.

s

Force the regeneration of the archive symbol table even if ar(1) is not invoked with a command which will modify the archive contents. This command is useful to restore the archive symbol table after the strip(1) command has been used on the archive.

SEE ALSO

ld(1), lorder(1), strip(1), a.out (4),ar(4)

NOTES

If the same file is mentioned twice in an argument list, it may be put in the archive twice.

By convention, archives are suffixed with the characters .a .