Ausam/doc/man/man5/archive.5

.th ARCHIVE V 9/10/73
.sh NAME
archive \*- ar (library) file format
.sh DESCRIPTION
The archive command
.it ar
is used to combine several files into
one.
Archives are used mainly as libraries to be searched
by the link-editor
.it ld.
.s3
A file produced by
.it ar
has a magic number at the start,
followed by the constituent files, each preceded by a file header.
The magic number is
177545(8)
(it was chosen to be unlikely to occur anywhere else).
The header of each file is 26 bytes long:
.s3
.nf
struct	{
	char	name[14];	/* file name, null padded on right */
	long	date;		/* time of last modification */
	int	uid;		/* uid of files owner */
	int	mode;		/* modes */
	long	size;		/* size of file */
};
.fi
.s3
.i0
Each file begins on a word boundary;
a null byte is inserted between files if necessary.
Nevertheless the size given reflects the
actual size of the file exclusive of padding.
.s3
Notice there is no provision for empty areas in an archive
file.
.sh "SEE ALSO"
ar (I), ld (I)
.sh BUGS