CPIO(4-SysV)        RISC/os Reference Manual         CPIO(4-SysV)



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 length struc-
     tures, archive, together with other items describing the
     file.  Every instance of h_magic contains the constant
     070707 (octal).  The h_dev and h_inode values combine to
     make one unsigned 32-bit number, rather than two shorts.  It
     is a number created by cpio to uniquely identify linked
     files.  The h_dev contains the high-order 16 bits of the
     32-bit number, and h_inode contains the low-order 16 bits of
     the 32-bit number.  This number does not reflect the actual
     device/inode pair of the file.  The first number assigned by
     cpio is 3, and is sequentially incremented for each file
     processed by cpio.  The items h_mode through h_mtime have
     meanings explained in stat(2).  The length of the null-
     terminated path name h_name, including the null byte, is
     given by h_namesize.

     The last record of the archive always contains the name
     TRAILER!!!.  Special files, directories, and the trailer are
     recorded with h_filesize equal to zero.




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CPIO(4-SysV)        RISC/os Reference Manual         CPIO(4-SysV)



SEE ALSO
     stat(2).
     cpio(1), find(1) in the User's Reference Manual.




















































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