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Trailing-Edge - PDP-10 Archives - SRI_NIC_PERM_FS_1_19910112 - c/old/include/ar.h
There are no other files named ar.h in the archive.
#define	ARMAG	"!<arch>\n"
#define	SARMAG	8

#define	ARFMAG	"`\n"

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];
};