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/* Extended tar format from POSIX.1.
Copyright (C) 1992, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by David J. MacKenzie.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _TAR_H
#define _TAR_H 1
/* A tar archive consists of 512-byte blocks.
Each file in the archive has a header block followed by 0+ data blocks.
Two blocks of NUL bytes indicate the end of the archive. */
/* The fields of header blocks:
All strings are stored as ISO 646 (approximately ASCII) strings.
Fields are numeric unless otherwise noted below; numbers are ISO 646
representations of octal numbers, with leading zeros as needed.
linkname is only valid when typeflag==LNKTYPE. It doesn't use prefix;
files that are links to pathnames >100 chars long can not be stored
in a tar archive.
If typeflag=={LNKTYPE,SYMTYPE,DIRTYPE} then size must be 0.
devmajor and devminor are only valid for typeflag=={BLKTYPE,CHRTYPE}.
chksum contains the sum of all 512 bytes in the header block,
treating each byte as an 8-bit unsigned value and treating the
8 bytes of chksum as blank characters.
uname and gname are used in preference to uid and gid, if those
names exist locally.
Field Name Byte Offset Length in Bytes Field Type
name 0 100 NUL-terminated if NUL fits
mode 100 8
uid 108 8
gid 116 8
size 124 12
mtime 136 12
chksum 148 8
typeflag 156 1 see below
linkname 157 100 NUL-terminated if NUL fits
magic 257 6 must be TMAGIC (NUL term.)
version 263 2 must be TVERSION
uname 265 32 NUL-terminated
gname 297 32 NUL-terminated
devmajor 329 8
devminor 337 8
prefix 345 155 NUL-terminated if NUL fits
If the first character of prefix is '\0', the file name is name;
otherwise, it is prefix/name. Files whose pathnames don't fit in that
length can not be stored in a tar archive. */
/* The bits in mode: */
#define TSUID 04000
#define TSGID 02000
#define TSVTX 01000
#define TUREAD 00400
#define TUWRITE 00200
#define TUEXEC 00100
#define TGREAD 00040
#define TGWRITE 00020
#define TGEXEC 00010
#define TOREAD 00004
#define TOWRITE 00002
#define TOEXEC 00001
/* The values for typeflag:
Values 'A'-'Z' are reserved for custom implementations.
All other values are reserved for future POSIX.1 revisions. */
#define REGTYPE '0' /* Regular file (preferred code). */
#define AREGTYPE '\0' /* Regular file (alternate code). */
#define LNKTYPE '1' /* Hard link. */
#define SYMTYPE '2' /* Symbolic link (hard if not supported). */
#define CHRTYPE '3' /* Character special. */
#define BLKTYPE '4' /* Block special. */
#define DIRTYPE '5' /* Directory. */
#define FIFOTYPE '6' /* Named pipe. */
#define CONTTYPE '7' /* Contiguous file */
/* (regular file if not supported). */
/* Contents of magic field and its length. */
#define TMAGIC "ustar"
#define TMAGLEN 6
/* Contents of the version field and its length. */
#define TVERSION "00"
#define TVERSLEN 2
#endif /* tar.h */