|
|
HP-UX Reference > Ccpio(4)HP-UX 11i Version 2: December 2007 Update |
|
NAMEcpio — format of cpio archive DESCRIPTIONThe header structure, when the -c option of cpio is not used (see cpio(1)), is: struct { short c_magic, c_dev; ushort c_ino, c_mode, c_uid, c_gid; short c_nlink, c_rdev, c_mtime[2], c_namesize, c_filesize[2]; char c_name[c_namesize rounded to word]; } Hdr; When the cpio -c option is used, the header information is described by: sscanf(Chdr,"%6ho%6ho%6ho%6ho%6ho%6ho%6ho%6ho%11lo%6ho%11lo", &Hdr.c_magic,&Hdr.c_dev,&Hdr.c_ino,&Hdr.c_mode, &Hdr.c_uid,&Hdr.c_gid,&Hdr.c_nlink,&Hdr.c_rdev, &Longtime,&Hdr.c_namesize,&Longfile); Longtime and Longfile are equivalent to Hdr.c_mtime and Hdr.c_filesize, respectively. The contents of each file are recorded together with other items describing the file. Every instance of c_magic contains the constant 070707 (octal). The items c_dev through c_mtime have meanings explained in stat(2). The length of the null-terminated path name c_name, including the null byte, is given by c_namesize. The last record of the archive always contains the name TRAILER!!!. Directories and the trailer are recorded with c_filesize equal to zero. It will not always be the case that c_dev and c_ino correspond to the results of stat(), but the values are always sufficient to tell whether two files in the archive are linked to each other. When a device special file is archived by HP-UX cpio (using the -x option), c_rdev contains a magic constant which is dependent upon the implementation doing the writing. H_rdev flags the device file as an HP-UX 32-bit device specifier, and c_filesize contains the 32-bit device specifier (see stat(2)). If the -x option is not present, special files are not archived or restored. Non-HPUX device special files are never restored. |
|