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Packit Service	1d0348	`TAR(5) BSD File Formats Manual TAR(5)`
Packit Service	1d0348
Packit Service	1d0348	`NAME`
Packit Service	1d0348
Packit Service	1d0348	`tar — format of`
Packit Service	1d0348	`tape archive files`
Packit Service	1d0348
Packit Service	1d0348	`DESCRIPTION`
Packit Service	1d0348
Packit Service	1d0348	`The tar archive format`
Packit Service	1d0348	`collects any number of files, directories, and other file`
Packit Service	1d0348	`system objects (symbolic links, device nodes, etc.) into a`
Packit Service	1d0348	`single stream of bytes. The format was originally designed`
Packit Service	1d0348	`to be used with tape drives that operate with fixed-size`
Packit Service	1d0348	`blocks, but is widely used as a general packaging`
Packit Service	1d0348	`mechanism.`
Packit Service	1d0348
Packit Service	1d0348	`General`
Packit Service	1d0348	`Format`
Packit Service	1d0348	`A tar archive consists of a series of 512-byte`
Packit Service	1d0348	`records. Each file system object requires a header record`
Packit Service	1d0348	`which stores basic metadata (pathname, owner, permissions,`
Packit Service	1d0348	`etc.) and zero or more records containing any file data. The`
Packit Service	1d0348	`end of the archive is indicated by two records consisting`
Packit Service	1d0348	`entirely of zero bytes.`
Packit Service	1d0348
Packit Service	1d0348	`For`
Packit Service	1d0348	`compatibility with tape drives that use fixed block sizes,`
Packit Service	1d0348	`programs that read or write tar files always read or write a`
Packit Service	1d0348	`fixed number of records with each I/O operation. These`
Packit Service	1d0348	`’’blocks’’ are always a multiple of`
Packit Service	1d0348	`the record size. The maximum block size supported by early`
Packit Service	1d0348	`implementations was 10240 bytes or 20 records. This is still`
Packit Service	1d0348	`the default for most implementations although block sizes of`
Packit Service	1d0348	`1MiB (2048 records) or larger are commonly used with modern`
Packit Service	1d0348	`high-speed tape drives. (Note: the terms`
Packit Service	1d0348	`’’block’’ and`
Packit Service	1d0348	`’’record’’ here are not entirely`
Packit Service	1d0348	`standard; this document follows the convention established`
Packit Service	1d0348	`by John Gilmore in documenting pdtar.)`
Packit Service	1d0348
Packit Service	1d0348	`Old-Style`
Packit Service	1d0348	`Archive Format`
Packit Service	1d0348	`The original tar archive format has been extended many times`
Packit Service	1d0348	`to include additional information that various implementors`
Packit Service	1d0348	`found necessary. This section describes the variant`
Packit Service	1d0348	`implemented by the tar command included in Version 7`
Packit Service	1d0348	`AT&T UNIX, which seems to be the earliest widely-used`
Packit Service	1d0348	`version of the tar program.`
Packit Service	1d0348
Packit Service	1d0348	`The header`
Packit Service	1d0348	`record for an old-style tar archive consists of the`
Packit Service	1d0348	`following:`
Packit Service	1d0348
Packit Service	1d0348	`struct`
Packit Service	1d0348	`header_old_tar {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`cellspacing="0" cellpadding="0">`
Packit Service	1d0348
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Packit Service	1d0348	`char name[100];`
Packit Service	1d0348
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Packit Service	1d0348	`char mode[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char uid[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char gid[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char size[12];`
Packit Service	1d0348
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Packit Service	1d0348	`char mtime[12];`
Packit Service	1d0348
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Packit Service	1d0348	`char checksum[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char linkflag[1];`
Packit Service	1d0348
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Packit Service	1d0348
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Packit Service	1d0348	`char linkname[100];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char pad[255];`
Packit Service	1d0348
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Packit Service	1d0348	`};`
Packit Service	1d0348
Packit Service	1d0348	`All unused bytes in the header`
Packit Service	1d0348	`record are filled with nulls.`
Packit Service	1d0348
Packit Service	1d0348	`name`
Packit Service	1d0348
Packit Service	1d0348	`Pathname,`
Packit Service	1d0348	`stored as a null-terminated string. Early tar`
Packit Service	1d0348	`implementations only stored regular files (including`
Packit Service	1d0348	`hardlinks to those files). One common early convention used`
Packit Service	1d0348	`a trailing "/" character to indicate a directory`
Packit Service	1d0348	`name, allowing directory permissions and owner information`
Packit Service	1d0348	`to be archived and restored.`
Packit Service	1d0348
Packit Service	1d0348	`mode`
Packit Service	1d0348
Packit Service	1d0348	`File mode,`
Packit Service	1d0348	`stored as an octal number in ASCII.`
Packit Service	1d0348
Packit Service	1d0348	`uid, gid`
Packit Service	1d0348
Packit Service	1d0348	`User id and group id of owner,`
Packit Service	1d0348	`as octal numbers in ASCII.`
Packit Service	1d0348
Packit Service	1d0348	`size`
Packit Service	1d0348
Packit Service	1d0348	`Size of file,`
Packit Service	1d0348	`as octal number in ASCII. For regular files only, this`
Packit Service	1d0348	`indicates the amount of data that follows the header. In`
Packit Service	1d0348	`particular, this field was ignored by early tar`
Packit Service	1d0348	`implementations when extracting hardlinks. Modern writers`
Packit Service	1d0348	`should always store a zero length for hardlink entries.`
Packit Service	1d0348
Packit Service	1d0348	`mtime`
Packit Service	1d0348
Packit Service	1d0348	`Modification`
Packit Service	1d0348	`time of file, as an octal number in ASCII. This indicates`
Packit Service	1d0348	`the number of seconds since the start of the epoch, 00:00:00`
Packit Service	1d0348	`UTC January 1, 1970. Note that negative values should be`
Packit Service	1d0348	`avoided here, as they are handled inconsistently.`
Packit Service	1d0348
Packit Service	1d0348	`checksum`
Packit Service	1d0348
Packit Service	1d0348	`Header checksum, stored as an`
Packit Service	1d0348	`octal number in ASCII. To compute the checksum, set the`
Packit Service	1d0348	`checksum field to all spaces, then sum all bytes in the`
Packit Service	1d0348	`header using unsigned arithmetic. This field should be`
Packit Service	1d0348	`stored as six octal digits followed by a null and a space`
Packit Service	1d0348	`character. Note that many early implementations of tar used`
Packit Service	1d0348	`signed arithmetic for the checksum field, which can cause`
Packit Service	1d0348	`interoperability problems when transferring archives between`
Packit Service	1d0348	`systems. Modern robust readers compute the checksum both`
Packit Service	1d0348	`ways and accept the header if either computation`
Packit Service	1d0348	`matches.`
Packit Service	1d0348
Packit Service	1d0348	`linkflag,`
Packit Service	1d0348	`linkname`
Packit Service	1d0348
Packit Service	1d0348	`In order to preserve hardlinks`
Packit Service	1d0348	`and conserve tape, a file with multiple links is only`
Packit Service	1d0348	`written to the archive the first time it is encountered. The`
Packit Service	1d0348	`next time it is encountered, the linkflag is set to`
Packit Service	1d0348	`an ASCII ’1’ and the linkname field holds`
Packit Service	1d0348	`the first name under which this file appears. (Note that`
Packit Service	1d0348	`regular files have a null value in the linkflag`
Packit Service	1d0348	`field.)`
Packit Service	1d0348
Packit Service	1d0348	`Early tar`
Packit Service	1d0348	`implementations varied in how they terminated these fields.`
Packit Service	1d0348	`The tar command in Version 7 AT&T UNIX used the`
Packit Service	1d0348	`following conventions (this is also documented in early BSD`
Packit Service	1d0348	`manpages): the pathname must be null-terminated; the mode,`
Packit Service	1d0348	`uid, and gid fields must end in a space and a null byte; the`
Packit Service	1d0348	`size and mtime fields must end in a space; the checksum is`
Packit Service	1d0348	`terminated by a null and a space. Early implementations`
Packit Service	1d0348	`filled the numeric fields with leading spaces. This seems to`
Packit Service	1d0348	`have been common practice until the IEEE Std 1003.1-1988`
Packit Service	1d0348	`(’’POSIX.1’’) standard was released.`
Packit Service	1d0348	`For best portability, modern implementations should fill the`
Packit Service	1d0348	`numeric fields with leading zeros.`
Packit Service	1d0348
Packit Service	1d0348	`Pre-POSIX`
Packit Service	1d0348	`Archives`
Packit Service	1d0348	`An early draft of IEEE Std 1003.1-1988`
Packit Service	1d0348	`(’’POSIX.1’’) served as the basis`
Packit Service	1d0348	`for John Gilmore’s pdtar program and many`
Packit Service	1d0348	`system implementations from the late 1980s and early 1990s.`
Packit Service	1d0348	`These archives generally follow the POSIX ustar format`
Packit Service	1d0348	`described below with the following variations:`
Packit Service	1d0348
Packit Service	1d0348	`•`
Packit Service	1d0348
Packit Service	1d0348	`The magic value consists of the`
Packit Service	1d0348	`five characters ’’ustar’’ followed`
Packit Service	1d0348	`by a space. The version field contains a space character`
Packit Service	1d0348	`followed by a null.`
Packit Service	1d0348
Packit Service	1d0348	`•`
Packit Service	1d0348
Packit Service	1d0348	`The numeric fields are`
Packit Service	1d0348	`generally filled with leading spaces (not leading zeros as`
Packit Service	1d0348	`recommended in the final standard).`
Packit Service	1d0348
Packit Service	1d0348	`•`
Packit Service	1d0348
Packit Service	1d0348	`The prefix field is often not`
Packit Service	1d0348	`used, limiting pathnames to the 100 characters of old-style`
Packit Service	1d0348	`archives.`
Packit Service	1d0348
Packit Service	1d0348	`POSIX ustar`
Packit Service	1d0348	`Archives`
Packit Service	1d0348	`IEEE Std 1003.1-1988 (’’POSIX.1’’)`
Packit Service	1d0348	`defined a standard tar file format to be read and written by`
Packit Service	1d0348	`compliant implementations of tar(1). This format is often`
Packit Service	1d0348	`called the ’’ustar’’ format, after`
Packit Service	1d0348	`the magic value used in the header. (The name is an acronym`
Packit Service	1d0348	`for ’’Unix Standard TAR’’.) It`
Packit Service	1d0348	`extends the historic format with new fields:`
Packit Service	1d0348
Packit Service	1d0348	`struct`
Packit Service	1d0348	`header_posix_ustar {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`cellspacing="0" cellpadding="0">`
Packit Service	1d0348
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Packit Service	1d0348	`char name[100];`
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Packit Service	1d0348	`char mode[8];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348	`char uid[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char gid[8];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char size[12];`
Packit Service	1d0348
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Packit Service	1d0348	`char mtime[12];`
Packit Service	1d0348
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Packit Service	1d0348	`char checksum[8];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char typeflag[1];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char linkname[100];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char magic[6];`
Packit Service	1d0348
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Packit Service	1d0348	`char version[2];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348	`char uname[32];`
Packit Service	1d0348
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Packit Service	1d0348
Packit Service	1d0348	`char gname[32];`
Packit Service	1d0348
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Packit Service	1d0348	`char devmajor[8];`
Packit Service	1d0348
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Packit Service	1d0348
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Packit Service	1d0348	`char devminor[8];`
Packit Service	1d0348
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Packit Service	1d0348	`char prefix[155];`
Packit Service	1d0348
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Packit Service	1d0348	`char pad[12];`
Packit Service	1d0348
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Packit Service	1d0348	`};`
Packit Service	1d0348
Packit Service	1d0348	`typeflag`
Packit Service	1d0348
Packit Service	1d0348	`Type of entry. POSIX extended`
Packit Service	1d0348	`the earlier linkflag field with several new type`
Packit Service	1d0348	`values:`
Packit Service	1d0348
Packit Service	1d0348	`’’0’’`
Packit Service	1d0348
Packit Service	1d0348	`Regular file.`
Packit Service	1d0348	`NUL should be treated as a synonym, for compatibility`
Packit Service	1d0348	`purposes.`
Packit Service	1d0348
Packit Service	1d0348	`’’1’’`
Packit Service	1d0348
Packit Service	1d0348	`Hard link.`
Packit Service	1d0348
Packit Service	1d0348	`’’2’’`
Packit Service	1d0348
Packit Service	1d0348	`Symbolic`
Packit Service	1d0348	`link.`
Packit Service	1d0348
Packit Service	1d0348	`’’3’’`
Packit Service	1d0348
Packit Service	1d0348	`Character`
Packit Service	1d0348	`device node.`
Packit Service	1d0348
Packit Service	1d0348	`’’4’’`
Packit Service	1d0348
Packit Service	1d0348	`Block device`
Packit Service	1d0348	`node.`
Packit Service	1d0348
Packit Service	1d0348	`’’5’’`
Packit Service	1d0348
Packit Service	1d0348	`Directory.`
Packit Service	1d0348
Packit Service	1d0348	`’’6’’`
Packit Service	1d0348
Packit Service	1d0348	`FIFO node.`
Packit Service	1d0348
Packit Service	1d0348	`’’7’’`
Packit Service	1d0348
Packit Service	1d0348	`Reserved.`
Packit Service	1d0348
Packit Service	1d0348	`Other`
Packit Service	1d0348
Packit Service	1d0348	`A`
Packit Service	1d0348	`POSIX-compliant implementation must treat any unrecognized`
Packit Service	1d0348	`typeflag value as a regular file. In particular, writers`
Packit Service	1d0348	`should ensure that all entries have a valid filename so that`
Packit Service	1d0348	`they can be restored by readers that do not support the`
Packit Service	1d0348	`corresponding extension. Uppercase letters "A"`
Packit Service	1d0348	`through "Z" are reserved for custom extensions.`
Packit Service	1d0348	`Note that sockets and whiteout entries are not`
Packit Service	1d0348	`archivable.`
Packit Service	1d0348
Packit Service	1d0348	`It is worth noting that the`
Packit Service	1d0348	`size field, in particular, has different meanings`
Packit Service	1d0348	`depending on the type. For regular files, of course, it`
Packit Service	1d0348	`indicates the amount of data following the header. For`
Packit Service	1d0348	`directories, it may be used to indicate the total size of`
Packit Service	1d0348	`all files in the directory, for use by operating systems`
Packit Service	1d0348	`that pre-allocate directory space. For all other types, it`
Packit Service	1d0348	`should be set to zero by writers and ignored by readers.`
Packit Service	1d0348
Packit Service	1d0348	`magic`
Packit Service	1d0348
Packit Service	1d0348	`Contains the`
Packit Service	1d0348	`magic value ’’ustar’’ followed by a`
Packit Service	1d0348	`NUL byte to indicate that this is a POSIX standard archive.`
Packit Service	1d0348	`Full compliance requires the uname and gname fields be`
Packit Service	1d0348	`properly set.`
Packit Service	1d0348
Packit Service	1d0348	`version`
Packit Service	1d0348
Packit Service	1d0348	`Version. This should be`
Packit Service	1d0348	`’’00’’ (two copies of the ASCII`
Packit Service	1d0348	`digit zero) for POSIX standard archives.`
Packit Service	1d0348
Packit Service	1d0348	`uname, gname`
Packit Service	1d0348
Packit Service	1d0348	`User and group names, as`
Packit Service	1d0348	`null-terminated ASCII strings. These should be used in`
Packit Service	1d0348	`preference to the uid/gid values when they are set and the`
Packit Service	1d0348	`corresponding names exist on the system.`
Packit Service	1d0348
Packit Service	1d0348	`devmajor,`
Packit Service	1d0348	`devminor`
Packit Service	1d0348
Packit Service	1d0348	`Major and minor numbers for`
Packit Service	1d0348	`character device or block device entry.`
Packit Service	1d0348
Packit Service	1d0348	`name, prefix`
Packit Service	1d0348
Packit Service	1d0348	`If the pathname is too long to`
Packit Service	1d0348	`fit in the 100 bytes provided by the standard format, it can`
Packit Service	1d0348	`be split at any / character with the first portion`
Packit Service	1d0348	`going into the prefix field. If the prefix field is not`
Packit Service	1d0348	`empty, the reader will prepend the prefix value and a`
Packit Service	1d0348	`/ character to the regular name field to obtain the`
Packit Service	1d0348	`full pathname. The standard does not require a trailing`
Packit Service	1d0348	`/ character on directory names, though most`
Packit Service	1d0348	`implementations still include this for compatibility`
Packit Service	1d0348	`reasons.`
Packit Service	1d0348
Packit Service	1d0348	`Note that all`
Packit Service	1d0348	`unused bytes must be set to NUL.`
Packit Service	1d0348
Packit Service	1d0348	`Field`
Packit Service	1d0348	`termination is specified slightly differently by POSIX than`
Packit Service	1d0348	`by previous implementations. The magic, uname,`
Packit Service	1d0348	`and gname fields must have a trailing NUL. The`
Packit Service	1d0348	`pathname, linkname, and prefix fields`
Packit Service	1d0348	`must have a trailing NUL unless they fill the entire field.`
Packit Service	1d0348	`(In particular, it is possible to store a 256-character`
Packit Service	1d0348	`pathname if it happens to have a / as the 156th`
Packit Service	1d0348	`character.) POSIX requires numeric fields to be zero-padded`
Packit Service	1d0348	`in the front, and requires them to be terminated with either`
Packit Service	1d0348	`space or NUL characters.`
Packit Service	1d0348
Packit Service	1d0348	`Currently, most`
Packit Service	1d0348	`tar implementations comply with the ustar format,`
Packit Service	1d0348	`occasionally extending it by adding new fields to the blank`
Packit Service	1d0348	`area at the end of the header record.`
Packit Service	1d0348
Packit Service	1d0348	`Numeric`
Packit Service	1d0348	`Extensions`
Packit Service	1d0348	`There have been several attempts to extend the range of`
Packit Service	1d0348	`sizes or times supported by modifying how numbers are stored`
Packit Service	1d0348	`in the header.`
Packit Service	1d0348
Packit Service	1d0348	`One obvious`
Packit Service	1d0348	`extension to increase the size of files is to eliminate the`
Packit Service	1d0348	`terminating characters from the various numeric fields. For`
Packit Service	1d0348	`example, the standard only allows the size field to contain`
Packit Service	1d0348	`11 octal digits, reserving the twelfth byte for a trailing`
Packit Service	1d0348	`NUL character. Allowing 12 octal digits allows file sizes up`
Packit Service	1d0348	`to 64 GB.`
Packit Service	1d0348
Packit Service	1d0348	`Another`
Packit Service	1d0348	`extension, utilized by GNU tar, star, and other newer`
Packit Service	1d0348	`tar implementations, permits binary numbers in the`
Packit Service	1d0348	`standard numeric fields. This is flagged by setting the high`
Packit Service	1d0348	`bit of the first byte. The remainder of the field is treated`
Packit Service	1d0348	`as a signed twos-complement value. This permits 95-bit`
Packit Service	1d0348	`values for the length and time fields and 63-bit values for`
Packit Service	1d0348	`the uid, gid, and device numbers. In particular, this`
Packit Service	1d0348	`provides a consistent way to handle negative time values.`
Packit Service	1d0348	`GNU tar supports this extension for the length, mtime,`
Packit Service	1d0348	`ctime, and atime fields. Joerg Schilling’s star`
Packit Service	1d0348	`program and the libarchive library support this extension`
Packit Service	1d0348	`for all numeric fields. Note that this extension is largely`
Packit Service	1d0348	`obsoleted by the extended attribute record provided by the`
Packit Service	1d0348	`pax interchange format.`
Packit Service	1d0348
Packit Service	1d0348	`Another early`
Packit Service	1d0348	`GNU extension allowed base-64 values rather than octal. This`
Packit Service	1d0348	`extension was short-lived and is no longer supported by any`
Packit Service	1d0348	`implementation.`
Packit Service	1d0348
Packit Service	1d0348	`Pax`
Packit Service	1d0348	`Interchange Format`
Packit Service	1d0348	`There are many attributes that cannot be portably stored in`
Packit Service	1d0348	`a POSIX ustar archive. IEEE Std 1003.1-2001`
Packit Service	1d0348	`(’’POSIX.1’’) defined a`
Packit Service	1d0348	`’’pax interchange format’’ that uses`
Packit Service	1d0348	`two new types of entries to hold text-formatted metadata`
Packit Service	1d0348	`that applies to following entries. Note that a pax`
Packit Service	1d0348	`interchange format archive is a ustar archive in every`
Packit Service	1d0348	`respect. The new data is stored in ustar-compatible archive`
Packit Service	1d0348	`entries that use the ’’x’’ or`
Packit Service	1d0348	`’’g’’ typeflag. In particular, older`
Packit Service	1d0348	`implementations that do not fully support these extensions`
Packit Service	1d0348	`will extract the metadata into regular files, where the`
Packit Service	1d0348	`metadata can be examined as necessary.`
Packit Service	1d0348
Packit Service	1d0348	`An entry in a`
Packit Service	1d0348	`pax interchange format archive consists of one or two`
Packit Service	1d0348	`standard ustar entries, each with its own header and data.`
Packit Service	1d0348	`The first optional entry stores the extended attributes for`
Packit Service	1d0348	`the following entry. This optional first entry has an`
Packit Service	1d0348	`"x" typeflag and a size field that indicates the`
Packit Service	1d0348	`total size of the extended attributes. The extended`
Packit Service	1d0348	`attributes themselves are stored as a series of text-format`
Packit Service	1d0348	`lines encoded in the portable UTF-8 encoding. Each line`
Packit Service	1d0348	`consists of a decimal number, a space, a key string, an`
Packit Service	1d0348	`equals sign, a value string, and a new line. The decimal`
Packit Service	1d0348	`number indicates the length of the entire line, including`
Packit Service	1d0348	`the initial length field and the trailing newline. An`
Packit Service	1d0348	`example of such a field is:`
Packit Service	1d0348
Packit Service	1d0348	`25 ctime=1084839148.1212\n`
Packit Service	1d0348
Packit Service	1d0348	`Keys in all lowercase are`
Packit Service	1d0348	`standard keys. Vendors can add their own keys by prefixing`
Packit Service	1d0348	`them with an all uppercase vendor name and a period. Note`
Packit Service	1d0348	`that, unlike the historic header, numeric values are stored`
Packit Service	1d0348	`using decimal, not octal. A description of some common keys`
Packit Service	1d0348	`follows:`
Packit Service	1d0348
Packit Service	1d0348	`atime, ctime,`
Packit Service	1d0348	`mtime`
Packit Service	1d0348
Packit Service	1d0348	`File access, inode change, and`
Packit Service	1d0348	`modification times. These fields can be negative or include`
Packit Service	1d0348	`a decimal point and a fractional value.`
Packit Service	1d0348
Packit Service	1d0348	`hdrcharset`
Packit Service	1d0348
Packit Service	1d0348	`The character set used by the`
Packit Service	1d0348	`pax extension values. By default, all textual values in the`
Packit Service	1d0348	`pax extended attributes are assumed to be in UTF-8,`
Packit Service	1d0348	`including pathnames, user names, and group names. In some`
Packit Service	1d0348	`cases, it is not possible to translate local conventions`
Packit Service	1d0348	`into UTF-8. If this key is present and the value is the`
Packit Service	1d0348	`six-character ASCII string`
Packit Service	1d0348	`’’BINARY’’, then all textual values`
Packit Service	1d0348	`are assumed to be in a platform-dependent multi-byte`
Packit Service	1d0348	`encoding. Note that there are only two valid values for this`
Packit Service	1d0348	`key: ’’BINARY’’ or`
Packit Service	1d0348	`’’ISO-IR 10646 2000 UTF-8’’.`
Packit Service	1d0348	`No other values are permitted by the standard, and the`
Packit Service	1d0348	`latter value should generally not be used as it is the`
Packit Service	1d0348	`default when this key is not specified. In particular, this`
Packit Service	1d0348	`flag should not be used as a general mechanism to allow`
Packit Service	1d0348	`filenames to be stored in arbitrary encodings.`
Packit Service	1d0348
Packit Service	1d0348	`uname, uid,`
Packit Service	1d0348	`gname, gid`
Packit Service	1d0348
Packit Service	1d0348	`User name, group name, and`
Packit Service	1d0348	`numeric UID and GID values. The user name and group name`
Packit Service	1d0348	`stored here are encoded in UTF8 and can thus include`
Packit Service	1d0348	`non-ASCII characters. The UID and GID fields can be of`
Packit Service	1d0348	`arbitrary length.`
Packit Service	1d0348
Packit Service	1d0348	`linkpath`
Packit Service	1d0348
Packit Service	1d0348	`The full path of the linked-to`
Packit Service	1d0348	`file. Note that this is encoded in UTF8 and can thus include`
Packit Service	1d0348	`non-ASCII characters.`
Packit Service	1d0348
Packit Service	1d0348	`path`
Packit Service	1d0348
Packit Service	1d0348	`The full`
Packit Service	1d0348	`pathname of the entry. Note that this is encoded in UTF8 and`
Packit Service	1d0348	`can thus include non-ASCII characters.`
Packit Service	1d0348
Packit Service	1d0348	`realtime.*,`
Packit Service	1d0348	`security.*`
Packit Service	1d0348
Packit Service	1d0348	`These keys are reserved and may`
Packit Service	1d0348	`be used for future standardization.`
Packit Service	1d0348
Packit Service	1d0348	`size`
Packit Service	1d0348
Packit Service	1d0348	`The size of the`
Packit Service	1d0348	`file. Note that there is no length limit on this field,`
Packit Service	1d0348	`allowing conforming archives to store files much larger than`
Packit Service	1d0348	`the historic 8GB limit.`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.*`
Packit Service	1d0348
Packit Service	1d0348	`Vendor-specific attributes used`
Packit Service	1d0348	`by Joerg Schilling’s star implementation.`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.acl.access,`
Packit Service	1d0348	`SCHILY.acl.default, SCHILY.acl.ace`
Packit Service	1d0348
Packit Service	1d0348	`Stores the access, default and`
Packit Service	1d0348	`NFSv4 ACLs as textual strings in a format that is an`
Packit Service	1d0348	`extension of the format specified by POSIX.1e draft 17. In`
Packit Service	1d0348	`particular, each user or group access specification can`
Packit Service	1d0348	`include an additional colon-separated field with the numeric`
Packit Service	1d0348	`UID or GID. This allows ACLs to be restored on systems that`
Packit Service	1d0348	`may not have complete user or group information available`
Packit Service	1d0348	`(such as when NIS/YP or LDAP services are temporarily`
Packit Service	1d0348	`unavailable).`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.devminor,`
Packit Service	1d0348	`SCHILY.devmajor`
Packit Service	1d0348
Packit Service	1d0348	`The full minor and major`
Packit Service	1d0348	`numbers for device nodes.`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.fflags`
Packit Service	1d0348
Packit Service	1d0348	`The file flags.`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.realsize`
Packit Service	1d0348
Packit Service	1d0348	`The full size of the file on`
Packit Service	1d0348	`disk. XXX explain? XXX`
Packit Service	1d0348
Packit Service	1d0348	`SCHILY.dev, SCHILY.ino,`
Packit Service	1d0348	`SCHILY.nlinks`
Packit Service	1d0348
Packit Service	1d0348	`The device number, inode`
Packit Service	1d0348	`number, and link count for the entry. In particular, note`
Packit Service	1d0348	`that a pax interchange format archive using Joerg`
Packit Service	1d0348	`Schilling’s SCHILY.* extensions can store all`
Packit Service	1d0348	`of the data from struct stat.`
Packit Service	1d0348
Packit Service	1d0348	`LIBARCHIVE.*`
Packit Service	1d0348
Packit Service	1d0348	`Vendor-specific attributes used`
Packit Service	1d0348	`by the libarchive library and programs that use`
Packit Service	1d0348	`it.`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`LIBARCHIVE.creationtime`
Packit Service	1d0348
Packit Service	1d0348	`The time when the file was`
Packit Service	1d0348	`created. (This should not be confused with the POSIX`
Packit Service	1d0348	`’’ctime’’ attribute, which refers to`
Packit Service	1d0348	`the time when the file metadata was last changed.)`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`LIBARCHIVE.xattr.namespace.key`
Packit Service	1d0348
Packit Service	1d0348	`Libarchive stores`
Packit Service	1d0348	`POSIX.1e-style extended attributes using keys of this form.`
Packit Service	1d0348	`The key value is URL-encoded: All non-ASCII`
Packit Service	1d0348	`characters and the two special characters`
Packit Service	1d0348	`’’=’’ and`
Packit Service	1d0348	`’’%’’ are encoded as`
Packit Service	1d0348	`’’%’’ followed by two uppercase`
Packit Service	1d0348	`hexadecimal digits. The value of this key is the extended`
Packit Service	1d0348	`attribute value encoded in base 64. XXX Detail the base-64`
Packit Service	1d0348	`format here XXX`
Packit Service	1d0348
Packit Service	1d0348	`VENDOR.*`
Packit Service	1d0348
Packit Service	1d0348	`XXX document other`
Packit Service	1d0348	`vendor-specific extensions XXX`
Packit Service	1d0348
Packit Service	1d0348	`Any values`
Packit Service	1d0348	`stored in an extended attribute override the corresponding`
Packit Service	1d0348	`values in the regular tar header. Note that compliant`
Packit Service	1d0348	`readers should ignore the regular fields when they are`
Packit Service	1d0348	`overridden. This is important, as existing archivers are`
Packit Service	1d0348	`known to store non-compliant values in the standard header`
Packit Service	1d0348	`fields in this situation. There are no limits on length for`
Packit Service	1d0348	`any of these fields. In particular, numeric fields can be`
Packit Service	1d0348	`arbitrarily large. All text fields are encoded in UTF8.`
Packit Service	1d0348	`Compliant writers should store only portable 7-bit ASCII`
Packit Service	1d0348	`characters in the standard ustar header and use extended`
Packit Service	1d0348	`attributes whenever a text value contains non-ASCII`
Packit Service	1d0348	`characters.`
Packit Service	1d0348
Packit Service	1d0348	`In addition to`
Packit Service	1d0348	`the x entry described above, the pax interchange`
Packit Service	1d0348	`format also supports a g entry. The g entry is`
Packit Service	1d0348	`identical in format, but specifies attributes that serve as`
Packit Service	1d0348	`defaults for all subsequent archive entries. The g`
Packit Service	1d0348	`entry is not widely used.`
Packit Service	1d0348
Packit Service	1d0348	`Besides the new`
Packit Service	1d0348	`x and g entries, the pax interchange format`
Packit Service	1d0348	`has a few other minor variations from the earlier ustar`
Packit Service	1d0348	`format. The most troubling one is that hardlinks are`
Packit Service	1d0348	`permitted to have data following them. This allows readers`
Packit Service	1d0348	`to restore any hardlink to a file without having to rewind`
Packit Service	1d0348	`the archive to find an earlier entry. However, it creates`
Packit Service	1d0348	`complications for robust readers, as it is no longer clear`
Packit Service	1d0348	`whether or not they should ignore the size field for`
Packit Service	1d0348	`hardlink entries.`
Packit Service	1d0348
Packit Service	1d0348	`GNU Tar`
Packit Service	1d0348	`Archives`
Packit Service	1d0348	`The GNU tar program started with a pre-POSIX format similar`
Packit Service	1d0348	`to that described earlier and has extended it using several`
Packit Service	1d0348	`different mechanisms: It added new fields to the empty space`
Packit Service	1d0348	`in the header (some of which was later used by POSIX for`
Packit Service	1d0348	`conflicting purposes); it allowed the header to be continued`
Packit Service	1d0348	`over multiple records; and it defined new entries that`
Packit Service	1d0348	`modify following entries (similar in principle to the`
Packit Service	1d0348	`x entry described above, but each GNU special entry`
Packit Service	1d0348	`is single-purpose, unlike the general-purpose x`
Packit Service	1d0348	`entry). As a result, GNU tar archives are not POSIX`
Packit Service	1d0348	`compatible, although more lenient POSIX-compliant readers`
Packit Service	1d0348	`can successfully extract most GNU tar archives.`
Packit Service	1d0348
Packit Service	1d0348	`struct`
Packit Service	1d0348	`header_gnu_tar {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`cellspacing="0" cellpadding="0">`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char name[100];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char mode[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char uid[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char gid[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char size[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char mtime[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char checksum[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char typeflag[1];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char linkname[100];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char magic[6];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char version[2];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char uname[32];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char gname[32];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char devmajor[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char devminor[8];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char atime[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char ctime[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char offset[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char longnames[4];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char unused[1];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`struct {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char offset[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char numbytes[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`} sparse[4];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char isextended[1];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char realsize[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char pad[17];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`};`
Packit Service	1d0348
Packit Service	1d0348	`typeflag`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar uses the following`
Packit Service	1d0348	`special entry types, in addition to those defined by`
Packit Service	1d0348	`POSIX:`
Packit Service	1d0348
Packit Service	1d0348	`7`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar treats`
Packit Service	1d0348	`type "7" records identically to type "0"`
Packit Service	1d0348	`records, except on one obscure RTOS where they are used to`
Packit Service	1d0348	`indicate the pre-allocation of a contiguous file on`
Packit Service	1d0348	`disk.`
Packit Service	1d0348
Packit Service	1d0348	`D`
Packit Service	1d0348
Packit Service	1d0348	`This indicates`
Packit Service	1d0348	`a directory entry. Unlike the POSIX-standard "5"`
Packit Service	1d0348	`typeflag, the header is followed by data records listing the`
Packit Service	1d0348	`names of files in this directory. Each name is preceded by`
Packit Service	1d0348	`an ASCII "Y" if the file is stored in this archive`
Packit Service	1d0348	`or "N" if the file is not stored in this archive.`
Packit Service	1d0348	`Each name is terminated with a null, and an extra null marks`
Packit Service	1d0348	`the end of the name list. The purpose of this entry is to`
Packit Service	1d0348	`support incremental backups; a program restoring from such`
Packit Service	1d0348	`an archive may wish to delete files on disk that did not`
Packit Service	1d0348	`exist in the directory when the archive was made.`
Packit Service	1d0348
Packit Service	1d0348	`Note that the`
Packit Service	1d0348	`"D" typeflag specifically violates POSIX, which`
Packit Service	1d0348	`requires that unrecognized typeflags be restored as normal`
Packit Service	1d0348	`files. In this case, restoring the "D" entry as a`
Packit Service	1d0348	`file could interfere with subsequent creation of the`
Packit Service	1d0348	`like-named directory.`
Packit Service	1d0348
Packit Service	1d0348	`K`
Packit Service	1d0348
Packit Service	1d0348	`The data for`
Packit Service	1d0348	`this entry is a long linkname for the following regular`
Packit Service	1d0348	`entry.`
Packit Service	1d0348
Packit Service	1d0348	`L`
Packit Service	1d0348
Packit Service	1d0348	`The data for`
Packit Service	1d0348	`this entry is a long pathname for the following regular`
Packit Service	1d0348	`entry.`
Packit Service	1d0348
Packit Service	1d0348	`M`
Packit Service	1d0348
Packit Service	1d0348	`This is a`
Packit Service	1d0348	`continuation of the last file on the previous volume. GNU`
Packit Service	1d0348	`multi-volume archives guarantee that each volume begins with`
Packit Service	1d0348	`a valid entry header. To ensure this, a file may be split,`
Packit Service	1d0348	`with part stored at the end of one volume, and part stored`
Packit Service	1d0348	`at the beginning of the next volume. The "M"`
Packit Service	1d0348	`typeflag indicates that this entry continues an existing`
Packit Service	1d0348	`file. Such entries can only occur as the first or second`
Packit Service	1d0348	`entry in an archive (the latter only if the first entry is a`
Packit Service	1d0348	`volume label). The size field specifies the size of`
Packit Service	1d0348	`this entry. The offset field at bytes 369-380`
Packit Service	1d0348	`specifies the offset where this file fragment begins. The`
Packit Service	1d0348	`realsize field specifies the total size of the file`
Packit Service	1d0348	`(which must equal size plus offset). When`
Packit Service	1d0348	`extracting, GNU tar checks that the header file name is the`
Packit Service	1d0348	`one it is expecting, that the header offset is in the`
Packit Service	1d0348	`correct sequence, and that the sum of offset and size is`
Packit Service	1d0348	`equal to realsize.`
Packit Service	1d0348
Packit Service	1d0348	`N`
Packit Service	1d0348
Packit Service	1d0348	`Type`
Packit Service	1d0348	`"N" records are no longer generated by GNU tar.`
Packit Service	1d0348	`They contained a list of files to be renamed or symlinked`
Packit Service	1d0348	`after extraction; this was originally used to support long`
Packit Service	1d0348	`names. The contents of this record are a text description of`
Packit Service	1d0348	`the operations to be done, in the form ’’Rename`
Packit Service	1d0348	`%s to %s\n’’ or ’’Symlink %s to`
Packit Service	1d0348	`%s\n’’; in either case, both filenames are`
Packit Service	1d0348	`escaped using K&R C syntax. Due to security concerns,`
Packit Service	1d0348	`"N" records are now generally ignored when reading`
Packit Service	1d0348	`archives.`
Packit Service	1d0348
Packit Service	1d0348	`S`
Packit Service	1d0348
Packit Service	1d0348	`This is a`
Packit Service	1d0348	`’’sparse’’ regular file. Sparse`
Packit Service	1d0348	`files are stored as a series of fragments. The header`
Packit Service	1d0348	`contains a list of fragment offset/length pairs. If more`
Packit Service	1d0348	`than four such entries are required, the header is extended`
Packit Service	1d0348	`as necessary with ’’extra’’ header`
Packit Service	1d0348	`extensions (an older format that is no longer used), or`
Packit Service	1d0348	`’’sparse’’ extensions.`
Packit Service	1d0348
Packit Service	1d0348	`V`
Packit Service	1d0348
Packit Service	1d0348	`The name`
Packit Service	1d0348	`field should be interpreted as a tape/volume header name.`
Packit Service	1d0348	`This entry should generally be ignored on extraction.`
Packit Service	1d0348
Packit Service	1d0348	`magic`
Packit Service	1d0348
Packit Service	1d0348	`The magic field`
Packit Service	1d0348	`holds the five characters ’’ustar’’`
Packit Service	1d0348	`followed by a space. Note that POSIX ustar archives have a`
Packit Service	1d0348	`trailing null.`
Packit Service	1d0348
Packit Service	1d0348	`version`
Packit Service	1d0348
Packit Service	1d0348	`The version field holds a space`
Packit Service	1d0348	`character followed by a null. Note that POSIX ustar archives`
Packit Service	1d0348	`use two copies of the ASCII digit`
Packit Service	1d0348	`’’0’’.`
Packit Service	1d0348
Packit Service	1d0348	`atime, ctime`
Packit Service	1d0348
Packit Service	1d0348	`The time the file was last`
Packit Service	1d0348	`accessed and the time of last change of file information,`
Packit Service	1d0348	`stored in octal as with mtime.`
Packit Service	1d0348
Packit Service	1d0348	`longnames`
Packit Service	1d0348
Packit Service	1d0348	`This field is apparently no`
Packit Service	1d0348	`longer used.`
Packit Service	1d0348
Packit Service	1d0348	`Sparse offset /`
Packit Service	1d0348	`numbytes`
Packit Service	1d0348
Packit Service	1d0348	`Each such structure specifies a`
Packit Service	1d0348	`single fragment of a sparse file. The two fields store`
Packit Service	1d0348	`values as octal numbers. The fragments are each padded to a`
Packit Service	1d0348	`multiple of 512 bytes in the archive. On extraction, the`
Packit Service	1d0348	`list of fragments is collected from the header (including`
Packit Service	1d0348	`any extension headers), and the data is then read and`
Packit Service	1d0348	`written to the file at appropriate offsets.`
Packit Service	1d0348
Packit Service	1d0348	`isextended`
Packit Service	1d0348
Packit Service	1d0348	`If this is set to non-zero, the`
Packit Service	1d0348	`header will be followed by additional ’’sparse`
Packit Service	1d0348	`header’’ records. Each such record contains`
Packit Service	1d0348	`information about as many as 21 additional sparse blocks as`
Packit Service	1d0348	`shown here:`
Packit Service	1d0348
Packit Service	1d0348	`struct`
Packit Service	1d0348	`gnu_sparse_header {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`cellspacing="0" cellpadding="0">`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`struct {`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char offset[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char numbytes[12];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`} sparse[21];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char isextended[1];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`char padding[7];`
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348
Packit Service	1d0348	`};`
Packit Service	1d0348
Packit Service	1d0348	`realsize`
Packit Service	1d0348
Packit Service	1d0348	`A binary representation of the`
Packit Service	1d0348	`file’s complete size, with a much larger range than`
Packit Service	1d0348	`the POSIX file size. In particular, with M type`
Packit Service	1d0348	`files, the current entry is only a portion of the file. In`
Packit Service	1d0348	`that case, the POSIX size field will indicate the size of`
Packit Service	1d0348	`this entry; the realsize field will indicate the`
Packit Service	1d0348	`total size of the file.`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar pax`
Packit Service	1d0348	`archives`
Packit Service	1d0348	`GNU tar 1.14 (XXX check this XXX) and later will write pax`
Packit Service	1d0348	`interchange format archives when you specify the`
Packit Service	1d0348	`--posix flag. This format follows the pax interchange`
Packit Service	1d0348	`format closely, using some SCHILY tags and`
Packit Service	1d0348	`introducing new keywords to store sparse file information.`
Packit Service	1d0348	`There have been three iterations of the sparse file support,`
Packit Service	1d0348	`referred to as ’’0.0’’,`
Packit Service	1d0348	`’’0.1’’, and`
Packit Service	1d0348	`’’1.0’’.`
Packit Service	1d0348
Packit Service	1d0348	`GNU.sparse.numblocks,`
Packit Service	1d0348	`GNU.sparse.offset, GNU.sparse.numbytes,`
Packit Service	1d0348	`GNU.sparse.size`
Packit Service	1d0348
Packit Service	1d0348	`The`
Packit Service	1d0348	`’’0.0’’ format used an initial`
Packit Service	1d0348	`GNU.sparse.numblocks attribute to indicate the number`
Packit Service	1d0348	`of blocks in the file, a pair of GNU.sparse.offset`
Packit Service	1d0348	`and GNU.sparse.numbytes to indicate the offset and`
Packit Service	1d0348	`size of each block, and a single GNU.sparse.size to`
Packit Service	1d0348	`indicate the full size of the file. This is not the same as`
Packit Service	1d0348	`the size in the tar header because the latter value does not`
Packit Service	1d0348	`include the size of any holes. This format required that the`
Packit Service	1d0348	`order of attributes be preserved and relied on readers`
Packit Service	1d0348	`accepting multiple appearances of the same attribute names,`
Packit Service	1d0348	`which is not officially permitted by the standards.`
Packit Service	1d0348
Packit Service	1d0348	`GNU.sparse.map`
Packit Service	1d0348
Packit Service	1d0348	`The`
Packit Service	1d0348	`’’0.1’’ format used a single`
Packit Service	1d0348	`attribute that stored a comma-separated list of decimal`
Packit Service	1d0348	`numbers. Each pair of numbers indicated the offset and size,`
Packit Service	1d0348	`respectively, of a block of data. This does not work well if`
Packit Service	1d0348	`the archive is extracted by an archiver that does not`
Packit Service	1d0348	`recognize this extension, since many pax implementations`
Packit Service	1d0348	`simply discard unrecognized attributes.`
Packit Service	1d0348
Packit Service	1d0348	`GNU.sparse.major,`
Packit Service	1d0348	`GNU.sparse.minor, GNU.sparse.name,`
Packit Service	1d0348	`GNU.sparse.realsize`
Packit Service	1d0348
Packit Service	1d0348	`The`
Packit Service	1d0348	`’’1.0’’ format stores the sparse`
Packit Service	1d0348	`block map in one or more 512-byte blocks prepended to the`
Packit Service	1d0348	`file data in the entry body. The pax attributes indicate the`
Packit Service	1d0348	`existence of this map (via the GNU.sparse.major and`
Packit Service	1d0348	`GNU.sparse.minor fields) and the full size of the`
Packit Service	1d0348	`file. The GNU.sparse.name holds the true name of the`
Packit Service	1d0348	`file. To avoid confusion, the name stored in the regular tar`
Packit Service	1d0348	`header is a modified name so that extraction errors will be`
Packit Service	1d0348	`apparent to users.`
Packit Service	1d0348
Packit Service	1d0348	`Solaris`
Packit Service	1d0348	`Tar`
Packit Service	1d0348	`XXX More Details Needed XXX`
Packit Service	1d0348
Packit Service	1d0348	`Solaris tar`
Packit Service	1d0348	`(beginning with SunOS XXX 5.7 ?? XXX) supports an`
Packit Service	1d0348	`’’extended’’ format that is`
Packit Service	1d0348	`fundamentally similar to pax interchange format, with the`
Packit Service	1d0348	`following differences:`
Packit Service	1d0348
Packit Service	1d0348	`•`
Packit Service	1d0348
Packit Service	1d0348	`Extended attributes are stored`
Packit Service	1d0348	`in an entry whose type is X, not x, as used by`
Packit Service	1d0348	`pax interchange format. The detailed format of this entry`
Packit Service	1d0348	`appears to be the same as detailed above for the x`
Packit Service	1d0348	`entry.`
Packit Service	1d0348
Packit Service	1d0348	`•`
Packit Service	1d0348
Packit Service	1d0348	`An additional A header`
Packit Service	1d0348	`is used to store an ACL for the following regular entry. The`
Packit Service	1d0348	`body of this entry contains a seven-digit octal number`
Packit Service	1d0348	`followed by a zero byte, followed by the textual ACL`
Packit Service	1d0348	`description. The octal value is the number of ACL entries`
Packit Service	1d0348	`plus a constant that indicates the ACL type: 01000000 for`
Packit Service	1d0348	`POSIX.1e ACLs and 03000000 for NFSv4 ACLs.`
Packit Service	1d0348
Packit Service	1d0348	`AIX Tar`
Packit Service	1d0348
Packit Service	1d0348	`XXX More details needed XXX`
Packit Service	1d0348
Packit Service	1d0348	`AIX Tar uses a`
Packit Service	1d0348	`ustar-formatted header with the type A for storing`
Packit Service	1d0348	`coded ACL information. Unlike the Solaris format, AIX tar`
Packit Service	1d0348	`writes this header after the regular file body to which it`
Packit Service	1d0348	`applies. The pathname in this header is either NFS4`
Packit Service	1d0348	`or AIXC to indicate the type of ACL stored. The`
Packit Service	1d0348	`actual ACL is stored in platform-specific binary format.`
Packit Service	1d0348
Packit Service	1d0348	`Mac OS X`
Packit Service	1d0348	`Tar`
Packit Service	1d0348	`The tar distributed with Apple’s Mac OS X stores most`
Packit Service	1d0348	`regular files as two separate files in the tar archive. The`
Packit Service	1d0348	`two files have the same name except that the first one has`
Packit Service	1d0348	`’’._’’ prepended to the last path`
Packit Service	1d0348	`element. This special file stores an AppleDouble-encoded`
Packit Service	1d0348	`binary blob with additional metadata about the second file,`
Packit Service	1d0348	`including ACL, extended attributes, and resources. To`
Packit Service	1d0348	`recreate the original file on disk, each separate file can`
Packit Service	1d0348	`be extracted and the Mac OS X copyfile() function can`
Packit Service	1d0348	`be used to unpack the separate metadata file and apply it to`
Packit Service	1d0348	`th regular file. Conversely, the same function provides a`
Packit Service	1d0348	`’’pack’’ option to encode the`
Packit Service	1d0348	`extended metadata from a file into a separate file whose`
Packit Service	1d0348	`contents can then be put into a tar archive.`
Packit Service	1d0348
Packit Service	1d0348	`Note that the`
Packit Service	1d0348	`Apple extended attributes interact badly with long`
Packit Service	1d0348	`filenames. Since each file is stored with the full name, a`
Packit Service	1d0348	`separate set of extensions needs to be included in the`
Packit Service	1d0348	`archive for each one, doubling the overhead required for`
Packit Service	1d0348	`files with long names.`
Packit Service	1d0348
Packit Service	1d0348	`Summary of`
Packit Service	1d0348	`tar type codes`
Packit Service	1d0348	`The following list is a condensed summary of the type codes`
Packit Service	1d0348	`used in tar header records generated by different tar`
Packit Service	1d0348	`implementations. More details about specific implementations`
Packit Service	1d0348	`can be found above:`
Packit Service	1d0348
Packit Service	1d0348	`NUL`
Packit Service	1d0348
Packit Service	1d0348	`Early tar`
Packit Service	1d0348	`programs stored a zero byte for regular files.`
Packit Service	1d0348
Packit Service	1d0348	`0`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a regular file.`
Packit Service	1d0348
Packit Service	1d0348	`1`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a hard link description.`
Packit Service	1d0348
Packit Service	1d0348	`2`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a symbolic link description.`
Packit Service	1d0348
Packit Service	1d0348	`3`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a character device node.`
Packit Service	1d0348
Packit Service	1d0348	`4`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a block device node.`
Packit Service	1d0348
Packit Service	1d0348	`5`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a directory.`
Packit Service	1d0348
Packit Service	1d0348	`6`
Packit Service	1d0348
Packit Service	1d0348	`POSIX standard`
Packit Service	1d0348	`type code for a FIFO.`
Packit Service	1d0348
Packit Service	1d0348	`7`
Packit Service	1d0348
Packit Service	1d0348	`POSIX`
Packit Service	1d0348	`reserved.`
Packit Service	1d0348
Packit Service	1d0348	`7`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar used`
Packit Service	1d0348	`for pre-allocated files on some systems.`
Packit Service	1d0348
Packit Service	1d0348	`A`
Packit Service	1d0348
Packit Service	1d0348	`Solaris tar ACL`
Packit Service	1d0348	`description stored prior to a regular file header.`
Packit Service	1d0348
Packit Service	1d0348	`A`
Packit Service	1d0348
Packit Service	1d0348	`AIX tar ACL`
Packit Service	1d0348	`description stored after the file body.`
Packit Service	1d0348
Packit Service	1d0348	`D`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar`
Packit Service	1d0348	`directory dump.`
Packit Service	1d0348
Packit Service	1d0348	`K`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar long`
Packit Service	1d0348	`linkname for the following header.`
Packit Service	1d0348
Packit Service	1d0348	`L`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar long`
Packit Service	1d0348	`pathname for the following header.`
Packit Service	1d0348
Packit Service	1d0348	`M`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar`
Packit Service	1d0348	`multivolume marker, indicating the file is a continuation of`
Packit Service	1d0348	`a file from the previous volume.`
Packit Service	1d0348
Packit Service	1d0348	`N`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar long`
Packit Service	1d0348	`filename support. Deprecated.`
Packit Service	1d0348
Packit Service	1d0348	`S`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar sparse`
Packit Service	1d0348	`regular file.`
Packit Service	1d0348
Packit Service	1d0348	`V`
Packit Service	1d0348
Packit Service	1d0348	`GNU tar`
Packit Service	1d0348	`tape/volume header name.`
Packit Service	1d0348
Packit Service	1d0348	`X`
Packit Service	1d0348
Packit Service	1d0348	`Solaris tar`
Packit Service	1d0348	`general-purpose extension header.`
Packit Service	1d0348
Packit Service	1d0348	`g`
Packit Service	1d0348
Packit Service	1d0348	`POSIX pax`
Packit Service	1d0348	`interchange format global extensions.`
Packit Service	1d0348
Packit Service	1d0348	`x`
Packit Service	1d0348
Packit Service	1d0348	`POSIX pax`
Packit Service	1d0348	`interchange format per-file extensions.`
Packit Service	1d0348
Packit Service	1d0348	`SEE ALSO`
Packit Service	1d0348
Packit Service	1d0348	`ar(1), pax(1), tar(1)`
Packit Service	1d0348
Packit Service	1d0348	`STANDARDS`
Packit Service	1d0348
Packit Service	1d0348	`The tar utility is no`
Packit Service	1d0348	`longer a part of POSIX or the Single Unix Standard. It last`
Packit Service	1d0348	`appeared in Version 2 of the Single UNIX Specification`
Packit Service	1d0348	`(’’SUSv2’’). It has been supplanted`
Packit Service	1d0348	`in subsequent standards by pax(1). The ustar format is`
Packit Service	1d0348	`currently part of the specification for the pax(1) utility.`
Packit Service	1d0348	`The pax interchange file format is new with IEEE Std`
Packit Service	1d0348	`1003.1-2001 (’’POSIX.1’’).`
Packit Service	1d0348
Packit Service	1d0348	`HISTORY`
Packit Service	1d0348
Packit Service	1d0348	`A tar command appeared in`
Packit Service	1d0348	`Seventh Edition Unix, which was released in January, 1979.`
Packit Service	1d0348	`It replaced the tp program from Fourth Edition Unix`
Packit Service	1d0348	`which in turn replaced the tap program from First`
Packit Service	1d0348	`Edition Unix. John Gilmore’s pdtar`
Packit Service	1d0348	`public-domain implementation (circa 1987) was highly`
Packit Service	1d0348	`influential and formed the basis of GNU tar (circa`
Packit Service	1d0348	`1988). Joerg Shilling’s star archiver is`
Packit Service	1d0348	`another open-source (CDDL) archiver (originally developed`
Packit Service	1d0348	`circa 1985) which features complete support for pax`
Packit Service	1d0348	`interchange format.`
Packit Service	1d0348
Packit Service	1d0348	`This`
Packit Service	1d0348	`documentation was written as part of the libarchive`
Packit Service	1d0348	`and bsdtar project by Tim Kientzle`
Packit Service	1d0348	`<kientzle@FreeBSD.org>.`
Packit Service	1d0348
Packit Service	1d0348	`BSD`
Packit Service	1d0348	`December 27, 2016 BSD`
Packit Service	1d0348
Packit Service	1d0348	`</body>`
Packit Service	1d0348	`</html>`

source-git / libarchive

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Blame doc/html/tar.5.html