AR(5) — UNIX Programmer’s Manual
NAME
ar − archive (library) file format
SYNOPSIS
#include <ar.h>
DESCRIPTION
N.B.: This archive format is new to this distribution. See old(8) and arcv(1) for programs to deal with the old format.
The archive command ar is used to combine several files into one. Archives are used mainly as libraries to be searched by the link-editor ld.
A file produced by ar 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:
/∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗ ∗∗∗∗∗∗∗∗∗∗∗∗∗
\ Copyright 1982
\ VALID LOGIC SYSTEMS INCORPORATED
This listing contains confidential proprietary information which is not to
be disclosed to unauthorized persons without written consent of an officer
of Valid Logic Systems Incorporated.
The copyright notice appearing above is included to provide statutory
protection in the event of unauthorized or unintentional public disclosure.
∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗ ∗∗∗∗∗∗∗∗∗∗/
#defineARMAG0177545
structar_hdr {
charar_name[14];
longar_date;
charar_uid;
charar_gid;
shortar_mode;
longar_size;
};
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 a even (0 mod 2) boundary; a new-line is inserted between files if necessary. Nevertheless the size given reflects the actual size of the file exclusive of padding.
There is no provision 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.
SEE ALSO
BUGS
File names lose trailing blanks. Most software dealing with archives takes even an included blank as a name terminator.
4th Berkeley Distribution — %W% %Q% %Y%