ultrix man page for ar

ar(5)								File Formats Manual							     ar(5)

Name
       ar - archive (library) file format

Syntax
       #include <ar.h>

Description
       The archive command, combines several files into one.  Archives are used mainly as libraries to be searched by the link-editor,

       A  file	produced  by has a magic string at the start, followed by the constituent files, each preceded by a file header.  The magic number
       and header layout as described in the include file are:
       #define ARMAG  "!<arch>
"
       #define SARMAG 8

       #define ARFMAG "`
"

       struct ar_hdr {
	       char   ar_name[16];
	       char   ar_date[12];
	       char   ar_uid[6];
	       char   ar_gid[6];
	       char   ar_mode[8];
	       char   ar_size[10];
	       char   ar_fmag[2];
       };

       The name is a blank-padded string.  The ar_fmag field contains ARFMAG to help verify the presence of a header.  The other fields are  left-
       adjusted, blank-padded numbers.	They are decimal except for ar_mode, which is octal.  The date is the modification date of the file at the
       time of its insertion into the archive.

       Each file begins on an even (0 mod 2) boundary; a new-line is inserted between files if necessary.  The size given reflects the actual size
       of the file exclusive of padding.

       Provisions are not made for empty areas in an archive file.

       The encoding of the header is portable across machines.	If an archive contains printable files, the archive itself is printable.

Restrictions
       A filename loses trailing blanks.  Most software dealing with archives takes an included blank as a name terminator.

See Also
       ar(1), ld(1), nm(1)

								       RISC								     ar(5)