CPIO(5)                     BSD Programmer's Manual                    CPIO(5)

NAME
     cpio - format of cpio archive

DESCRIPTION
     The header structure, when the -c option of cpio(1) is not used, is:

           struct {
                   short   h_magic,
                           h_dev;
                   ushort  h_ino,
                           h_mode,
                           h_uid,
                           h_gid;
                   short   h_nlink,
                           h_rdev,
                           h_mtime[2],
                           h_namesize,
                           h_filesize[2];
                   char    h_name[h_namesize rounded to word];
           } Hdr;

     When the -c option is used, the header information is described by:

           sscanf(Chdr,"%6o%6o%6o%6o%6o%6o%6o%6o%11lo%6o%11lo%s",
           &Hdr.h_magic, &Hdr.h_dev, &Hdr.h_ino, &Hdr.h_mode,
           &Hdr.h_uid, &Hdr.h_gid, &Hdr.h_nlink, &Hdr.h_rdev,
           &Longtime, &Hdr.h_namesize,&Longfile,Hdr.h_name);

     Longtime and Longfile are equivalent to Hdr.h_mtime and Hdr.h_filesize,
     respectively.  The contents of each file are recorded in an element of
     the array of varying lenght structures, archive, together with other
     items describing the file.  Every instance of h_magic contains the con-
     stant 070707 (octal).  The itimes h_dev through h_mtime have meanings ex-
     plained in stat(2).  The length of the null-terminated path name H_name,
     icluding the null byte, is given by h_namesize.

     The last record of the archive always contains the name TRAILER!!!.  Spe-
     cial files, directories, and the trailer are recorded with H_filesize
     equal to zero.

SEE ALSO
     cpio(1),  find(1),  stat(2)

HISTORY
     A cpio(1) command appeared in AT&T System V UNIX.  This file format is
     derived from the AT&T System V UNIX sources which were contributed to the
     public domain by AT&T.

BSDI BSD/386                    March 27, 1993                               1