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diff --git a/libarchive/libarchive-2.8.0/doc/html/cpio.5.html b/libarchive/libarchive-2.8.0/doc/html/cpio.5.html new file mode 100644 index 0000000..8d4768d --- /dev/null +++ b/libarchive/libarchive-2.8.0/doc/html/cpio.5.html @@ -0,0 +1,422 @@ +<!-- Creator : groff version 1.19.2 --> +<!-- CreationDate: Thu Feb 4 20:36:34 2010 --> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" +"http://www.w3.org/TR/html4/loose.dtd"> +<html> +<head> +<meta name="generator" content="groff -Thtml, see www.gnu.org"> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<meta name="Content-Style" content="text/css"> +<style type="text/css"> + p { margin-top: 0; margin-bottom: 0; } + pre { margin-top: 0; margin-bottom: 0; } + table { margin-top: 0; margin-bottom: 0; } +</style> +<title></title> +</head> +<body> + +<hr> + + +<p valign="top">CPIO(5) FreeBSD File Formats Manual +CPIO(5)</p> + +<p style="margin-top: 1em" valign="top"><b>NAME</b></p> + +<p style="margin-left:8%;"><b>cpio</b> — format of +cpio archive files</p> + + +<p style="margin-top: 1em" valign="top"><b>DESCRIPTION</b></p> + +<p style="margin-left:8%;">The <b>cpio</b> archive format +collects any number of files, directories, and other file +system objects (symbolic links, device nodes, etc.) into a +single stream of bytes.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>General +Format</b> <br> +Each file system object in a <b>cpio</b> archive comprises a +header record with basic numeric metadata followed by the +full pathname of the entry and the file data. The header +record stores a series of integer values that generally +follow the fields in <i>struct stat</i>. (See stat(2) for +details.) The variants differ primarily in how they store +those integers (binary, octal, or hexadecimal). The header +is followed by the pathname of the entry (the length of the +pathname is stored in the header) and any file data. The end +of the archive is indicated by a special record with the +pathname ‘‘TRAILER!!!’’.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>PWB +format</b> <br> +XXX Any documentation of the original PWB/UNIX 1.0 format? +XXX</p> + +<p style="margin-left:8%; margin-top: 1em"><b>Old Binary +Format</b> <br> +The old binary <b>cpio</b> format stores numbers as 2-byte +and 4-byte binary values. Each entry begins with a header in +the following format:</p> + +<p style="margin-left:17%; margin-top: 1em">struct +header_old_cpio { <br> +unsigned short c_magic; <br> +unsigned short c_dev; <br> +unsigned short c_ino; <br> +unsigned short c_mode; <br> +unsigned short c_uid; <br> +unsigned short c_gid; <br> +unsigned short c_nlink; <br> +unsigned short c_rdev;</p> + +<table width="100%" border=0 rules="none" frame="void" + cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="29%"></td> +<td width="13%"> + + +<p valign="top">unsigned short c_mtime[2];</p></td> +<td width="58%"> +</td> +</table> + +<p style="margin-left:17%;">unsigned short c_namesize;</p> + +<table width="100%" border=0 rules="none" frame="void" + cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="29%"></td> +<td width="71%"> + + +<p valign="top">unsigned short c_filesize[2];</p></td> +</table> + +<p style="margin-left:17%;">};</p> + +<p style="margin-left:8%; margin-top: 1em">The <i>unsigned +short</i> fields here are 16-bit integer values; the +<i>unsigned int</i> fields are 32-bit integer values. The +fields are as follows</p> + +<p style="margin-top: 1em" valign="top"><i>magic</i></p> + +<p style="margin-left:20%; margin-top: 1em">The integer +value octal 070707. This value can be used to determine +whether this archive is written with little-endian or +big-endian integers.</p> + +<p style="margin-top: 1em" valign="top"><i>dev</i>, +<i>ino</i></p> + +<p style="margin-left:20%;">The device and inode numbers +from the disk. These are used by programs that read +<b>cpio</b> archives to determine when two entries refer to +the same file. Programs that synthesize <b>cpio</b> archives +should be careful to set these to distinct values for each +entry.</p> + +<p style="margin-top: 1em" valign="top"><i>mode</i></p> + +<p style="margin-left:20%; margin-top: 1em">The mode +specifies both the regular permissions and the file type. It +consists of several bit fields as follows:</p> + +<p valign="top">0170000</p> + +<p style="margin-left:34%; margin-top: 1em">This masks the +file type bits.</p> + +<p valign="top">0140000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for sockets.</p> + +<p valign="top">0120000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for symbolic links. For symbolic links, the link body is +stored as file data.</p> + +<p valign="top">0100000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for regular files.</p> + +<p valign="top">0060000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for block special devices.</p> + +<p valign="top">0040000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for directories.</p> + +<p valign="top">0020000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for character special devices.</p> + +<p valign="top">0010000</p> + +<p style="margin-left:34%; margin-top: 1em">File type value +for named pipes or FIFOs.</p> + +<p valign="top">0004000</p> + +<p style="margin-left:34%; margin-top: 1em">SUID bit.</p> + +<p valign="top">0002000</p> + +<p style="margin-left:34%; margin-top: 1em">SGID bit.</p> + +<p valign="top">0001000</p> + +<p style="margin-left:34%; margin-top: 1em">Sticky bit. On +some systems, this modifies the behavior of executables +and/or directories.</p> + +<p valign="top">0000777</p> + +<p style="margin-left:34%; margin-top: 1em">The lower 9 +bits specify read/write/execute permissions for world, +group, and user following standard POSIX conventions.</p> + +<p style="margin-top: 1em" valign="top"><i>uid</i>, +<i>gid</i></p> + +<p style="margin-left:20%;">The numeric user id and group +id of the owner.</p> + +<p style="margin-top: 1em" valign="top"><i>nlink</i></p> + +<p style="margin-left:20%; margin-top: 1em">The number of +links to this file. Directories always have a value of at +least two here. Note that hardlinked files include file data +with every copy in the archive.</p> + +<p style="margin-top: 1em" valign="top"><i>rdev</i></p> + +<p style="margin-left:20%; margin-top: 1em">For block +special and character special entries, this field contains +the associated device number. For all other entry types, it +should be set to zero by writers and ignored by readers.</p> + +<p style="margin-top: 1em" valign="top"><i>mtime</i></p> + +<p style="margin-left:20%; margin-top: 1em">Modification +time of the file, indicated as the number of seconds since +the start of the epoch, 00:00:00 UTC January 1, 1970. The +four-byte integer is stored with the most-significant 16 +bits first followed by the least-significant 16 bits. Each +of the two 16 bit values are stored in machine-native byte +order.</p> + + +<p style="margin-top: 1em" valign="top"><i>namesize</i></p> + +<p style="margin-left:20%;">The number of bytes in the +pathname that follows the header. This count includes the +trailing NUL byte.</p> + + +<p style="margin-top: 1em" valign="top"><i>filesize</i></p> + +<p style="margin-left:20%;">The size of the file. Note that +this archive format is limited to four gigabyte file sizes. +See <i>mtime</i> above for a description of the storage of +four-byte integers.</p> + +<p style="margin-left:8%; margin-top: 1em">The pathname +immediately follows the fixed header. If the <b>namesize</b> +is odd, an additional NUL byte is added after the pathname. +The file data is then appended, padded with NUL bytes to an +even length.</p> + +<p style="margin-left:8%; margin-top: 1em">Hardlinked files +are not given special treatment; the full file contents are +included with each copy of the file.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>Portable +ASCII Format</b> <br> +Version 2 of the Single UNIX Specification +(‘‘SUSv2’’) standardized an ASCII +variant that is portable across all platforms. It is +commonly known as the ‘‘old +character’’ format or as the +‘‘odc’’ format. It stores the same +numeric fields as the old binary format, but represents them +as 6-character or 11-character octal values.</p> + +<p style="margin-left:17%; margin-top: 1em">struct +cpio_odc_header { <br> +char c_magic[6]; <br> +char c_dev[6]; <br> +char c_ino[6]; <br> +char c_mode[6]; <br> +char c_uid[6]; <br> +char c_gid[6]; <br> +char c_nlink[6]; <br> +char c_rdev[6]; <br> +char c_mtime[11]; <br> +char c_namesize[6]; <br> +char c_filesize[11]; <br> +};</p> + +<p style="margin-left:8%; margin-top: 1em">The fields are +identical to those in the old binary format. The name and +file body follow the fixed header. Unlike the old binary +format, there is no additional padding after the pathname or +file contents. If the files being archived are themselves +entirely ASCII, then the resulting archive will be entirely +ASCII, except for the NUL byte that terminates the name +field.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>New ASCII +Format</b> <br> +The "new" ASCII format uses 8-byte hexadecimal +fields for all numbers and separates device numbers into +separate fields for major and minor numbers.</p> + +<p style="margin-left:17%; margin-top: 1em">struct +cpio_newc_header { <br> +char c_magic[6]; <br> +char c_ino[8]; <br> +char c_mode[8]; <br> +char c_uid[8]; <br> +char c_gid[8]; <br> +char c_nlink[8]; <br> +char c_mtime[8]; <br> +char c_filesize[8]; <br> +char c_devmajor[8]; <br> +char c_devminor[8]; <br> +char c_rdevmajor[8]; <br> +char c_rdevminor[8]; <br> +char c_namesize[8]; <br> +char c_check[8]; <br> +};</p> + +<p style="margin-left:8%; margin-top: 1em">Except as +specified below, the fields here match those specified for +the old binary format above.</p> + +<p style="margin-top: 1em" valign="top"><i>magic</i></p> + +<p style="margin-left:20%; margin-top: 1em">The string +‘‘070701’’.</p> + +<p style="margin-top: 1em" valign="top"><i>check</i></p> + +<p style="margin-left:20%; margin-top: 1em">This field is +always set to zero by writers and ignored by readers. See +the next section for more details.</p> + +<p style="margin-left:8%; margin-top: 1em">The pathname is +followed by NUL bytes so that the total size of the fixed +header plus pathname is a multiple of four. Likewise, the +file data is padded to a multiple of four bytes. Note that +this format supports only 4 gigabyte files (unlike the older +ASCII format, which supports 8 gigabyte files).</p> + +<p style="margin-left:8%; margin-top: 1em">In this format, +hardlinked files are handled by setting the filesize to zero +for each entry except the last one that appears in the +archive.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>New CRC +Format</b> <br> +The CRC format is identical to the new ASCII format +described in the previous section except that the magic +field is set to ‘‘070702’’ and the +<i>check</i> field is set to the sum of all bytes in the +file data. This sum is computed treating all bytes as +unsigned values and using unsigned arithmetic. Only the +least-significant 32 bits of the sum are stored.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>HP +variants</b> <br> +The <b>cpio</b> implementation distributed with HPUX used +XXXX but stored device numbers differently XXX.</p> + +<p style="margin-left:8%; margin-top: 1em"><b>Other +Extensions and Variants</b> <br> +Sun Solaris uses additional file types to store extended +file data, including ACLs and extended attributes, as +special entries in cpio archives.</p> + +<p style="margin-left:8%; margin-top: 1em">XXX Others? +XXX</p> + +<p style="margin-top: 1em" valign="top"><b>BUGS</b></p> + +<p style="margin-left:8%;">The +‘‘CRC’’ format is mis-named, as it +uses a simple checksum and not a cyclic redundancy +check.</p> + +<p style="margin-left:8%; margin-top: 1em">The old binary +format is limited to 16 bits for user id, group id, device, +and inode numbers. It is limited to 4 gigabyte file +sizes.</p> + +<p style="margin-left:8%; margin-top: 1em">The old ASCII +format is limited to 18 bits for the user id, group id, +device, and inode numbers. It is limited to 8 gigabyte file +sizes.</p> + +<p style="margin-left:8%; margin-top: 1em">The new ASCII +format is limited to 4 gigabyte file sizes.</p> + +<p style="margin-left:8%; margin-top: 1em">None of the cpio +formats store user or group names, which are essential when +moving files between systems with dissimilar user or group +numbering.</p> + +<p style="margin-left:8%; margin-top: 1em">Especially when +writing older cpio variants, it may be necessary to map +actual device/inode values to synthesized values that fit +the available fields. With very large filesystems, this may +be necessary even for the newer formats.</p> + +<p style="margin-top: 1em" valign="top"><b>SEE ALSO</b></p> + +<p style="margin-left:8%;">cpio(1), tar(5)</p> + + +<p style="margin-top: 1em" valign="top"><b>STANDARDS</b></p> + +<p style="margin-left:8%;">The <b>cpio</b> utility is no +longer a part of POSIX or the Single Unix Standard. It last +appeared in Version 2 of the Single UNIX Specification +(‘‘SUSv2’’). It has been supplanted +in subsequent standards by pax(1). The portable ASCII format +is currently part of the specification for the pax(1) +utility.</p> + +<p style="margin-top: 1em" valign="top"><b>HISTORY</b></p> + +<p style="margin-left:8%;">The original cpio utility was +written by Dick Haight while working in AT&T’s +Unix Support Group. It appeared in 1977 as part of PWB/UNIX +1.0, the ‘‘Programmer’s Work +Bench’’ derived from Version 6 AT&T +UNIX that was used internally at AT&T. Both the old +binary and old character formats were in use by 1980, +according to the System III source released by SCO under +their ‘‘Ancient Unix’’ license. The +character format was adopted as part of IEEE Std 1003.1-1988 +(‘‘POSIX.1’’). XXX when did +"newc" appear? Who invented it? When did HP come +out with their variant? When did Sun introduce ACLs and +extended attributes? XXX</p> + + +<p style="margin-left:8%; margin-top: 1em">FreeBSD 8.0 +October 5, 2007 FreeBSD 8.0</p> +<hr> +</body> +</html> |