cpio.5

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)cpio.5	8.1	9/11/90
.TH cpio 5 
.SH Name
cpio \- format of cpio archive
.SH Description
.NXR "cpio file" "format"
.NXAM "cpio command" "cpio file"
The header
structure, when the
.PN \-c
option of 
.MS cpio 1
is not used, is:
.EX
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;
.EE
When the 
.PN \-c
option is used, the header
information is described by:
.EX 
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);
.EE
The
.I Longtime
and
.I Longfile 
are equivalent to 
.I Hdr.h_mtime
and
.I Hdr.h_filesize,
respectively.  The contents of each file are recorded in an
element of the array of varying length structures,
.I archive,
together with other items describing the file.
Every instance of
.I h_magic
contains the constant 070707 (octal).  The items
.I h_dev 
through
.I h_mtime
have meanings explained in 
.MS stat 2 .
The length of the null-terminated path name
.IR h_name , 
including the null byte, is given by
.IR h_namesize .
.PP
The last record of the
.I archive
always contains the name 
.PN TRAILER!!!
Special
files, directories, and the trailer are recorded
with
.I h_filesize
equal to zero.
.SH See Also
cpio(1), find(1), stat(2)