V1/man/man5/archive.5

        11/3/71                                                   ARCHIVE (V)


NAME              archive (library) file format

SYNOPSIS

DESCRIPTION       The archive command ar is used to combine several files
                  into one. Its use has three benefits: when files are
                  combined, the file space consumed by the breakage at the
                  end of each file (256 bytes on the average) is saved;
                  directories are smaller and less confusing; archive files
                  of object programs may be searched as libraries by the
                  loader ld.

                  A file produced by ar has a "magic number" at the start,
                  followed by the constituent files, each preceded by a file
                  header. The magic number is --147(10), or 177555(8) (it was
                  chosen to be unlikely to occur anywhere else). The header
                  of each file is 16 bytes long:

                                     0--7
                        file name, null padded on the right

                                    8--Il
                        Modification time of the file

                                     12
                        User ID of file owner

                                     13
                        file mode

                                    14--15
                       file size

                  If the file is an odd number of bytes long, it is padded
                  with a null byte, but the size in the header is correct.

                  Notice there is no provision for empty areas in an archive
                  file.

FILES

SEE ALSO

DIAGNOSTICS

BUGS

OWNER             ken, dmr