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- ARCHIVE_WRITE_OPTIONS(3) manual page
- == NAME ==
- '''archive_write_set_filter_option''',
- '''archive_write_set_format_option''',
- '''archive_write_set_option''',
- '''archive_write_set_options'''
- - functions controlling options for writing archives
- == LIBRARY ==
- Streaming Archive Library (libarchive, -larchive)
- == SYNOPSIS ==
- <br>
- ''int''
- <br>
- '''archive_write_set_filter_option'''(''struct archive *'', ''const char *module'', ''const char *option'', ''const char *value'');
- <br>
- ''int''
- <br>
- '''archive_write_set_format_option'''(''struct archive *'', ''const char *module'', ''const char *option'', ''const char *value'');
- <br>
- ''int''
- <br>
- '''archive_write_set_option'''(''struct archive *'', ''const char *module'', ''const char *option'', ''const char *value'');
- <br>
- ''int''
- <br>
- '''archive_write_set_options'''(''struct archive *'', ''const char *options'');
- == DESCRIPTION ==
- These functions provide a way for libarchive clients to configure
- specific write modules.
- <dl>
- <dt>
- '''archive_write_set_filter_option'''(),
- '''archive_write_set_format_option'''()
- </dt> <dd>
- Specifies an option that will be passed to the currently-registered
- filters (including decompression filters) or format readers.
- If
- ''option''
- and
- ''value''
- are both
- NULL,
- these functions will do nothing and
- '''ARCHIVE_OK'''
- will be returned.
- If
- ''option''
- is
- NULL
- but
- ''value''
- is not, these functions will do nothing and
- '''ARCHIVE_FAILED'''
- will be returned.
- If
- ''module''
- is not
- NULL,
- ''option''
- and
- ''value''
- will be provided to the filter or reader named
- ''module''.
- The return value will be either
- '''ARCHIVE_OK'''
- if the option was successfully handled or
- '''ARCHIVE_WARN'''
- if the option was unrecognized by the module or could otherwise
- not be handled.
- If there is no such module,
- '''ARCHIVE_FAILED'''
- will be returned.
- If
- ''module''
- is
- NULL,
- ''option''
- and
- ''value''
- will be provided to every registered module.
- If any module returns
- '''ARCHIVE_FATAL''',
- this value will be returned immediately.
- Otherwise,
- '''ARCHIVE_OK'''
- will be returned if any module accepts the option, and
- '''ARCHIVE_FAILED'''
- in all other cases.
- </dd><dt>'''archive_write_set_option'''()</dt><dd>
- Calls
- '''archive_write_set_format_option'''(),
- then
- '''archive_write_set_filter_option'''().
- If either function returns
- '''ARCHIVE_FATAL''',
- '''ARCHIVE_FATAL'''
- will be returned
- immediately.
- Otherwise, the greater of the two values will be returned.
- </dd><dt>'''archive_write_set_options'''()</dt><dd>
- ''options''
- is a comma-separated list of options.
- If
- ''options''
- is
- NULL
- or empty,
- '''ARCHIVE_OK'''
- will be returned immediately.
- Individual options have one of the following forms:
- <dl>
- <dt>''option=value''</dt><dd>
- The option/value pair will be provided to every module.
- Modules that do not accept an option with this name will ignore it.
- </dd><dt>''option''</dt><dd>
- The option will be provided to every module with a value of
- "1".
- </dd><dt>''!option''</dt><dd>
- The option will be provided to every module with a NULL value.
- </dd><dt>''module:option=value'', ''module:option'', ''module:!option''</dt><dd>
- As above, but the corresponding option and value will be provided
- only to modules whose name matches
- ''module''.
- </dd></dl>
- </dd></dl>
- == OPTIONS ==
- <dl>
- <dt>Filter b64encode</dt><dd>
- <dl>
- <dt>'''mode'''</dt><dd>
- The value is interpreted as octal digits specifying the file mode.
- </dd><dt>'''name'''</dt><dd>
- The value specifies the file name.
- </dd></dl>
- </dd><dt>Filter bzip2</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- bzip2 compression level. Supported values are from 1 to 9.
- </dd></dl>
- </dd><dt>Filter gzip</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- gzip compression level. Supported values are from 0 to 9.
- </dd><dt>'''timestamp'''</dt><dd>
- Store timestamp. This is enabled by default.
- </dd></dl>
- </dd><dt>Filter lrzip</dt><dd>
- <dl>
- <dt>'''compression'''=''type''</dt><dd>
- Use
- ''type''
- as compression method.
- Supported values are
- "bzip2",
- "gzipi",
- "lzo"
- (ultra fast,)
- and
- "zpaq"
- (best, extremely slow.)
- </dd><dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- lrzip compression level. Supported values are from 1 to 9.
- </dd></dl>
- </dd><dt>Filter lz4</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- lz4 compression level. Supported values are from 0 to 9.
- </dd><dt>'''stream-checksum'''</dt><dd>
- Enable stream checksum. This is enabled by default.
- </dd><dt>'''block-checksum'''</dt><dd>
- Enable block checksum. This is disabled by default.
- </dd><dt>'''block-size'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- lz4 compression block size. Supported values are from 4 to 7
- (default.)
- </dd><dt>'''block-dependence'''</dt><dd>
- Use the previous block of the block being compressed for
- a compression dictionary to improve compression ratio.
- This is disabled by default.
- </dd></dl>
- </dd><dt>Filter lzop</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- lzop compression level. Supported values are from 1 to 9.
- </dd></dl>
- </dd><dt>Filter uuencode</dt><dd>
- <dl>
- <dt>'''mode'''</dt><dd>
- The value is interpreted as octal digits specifying the file mode.
- </dd><dt>'''name'''</dt><dd>
- The value specifies the file name.
- </dd></dl>
- </dd><dt>Filter xz</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- compression level. Supported values are from 0 to 9.
- </dd><dt>'''threads'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- number of threads for multi-threaded lzma compression.
- If supported, the default value is read from
- '''lzma_cputhreads'''().
- </dd></dl>
- </dd><dt>Filter zstd</dt><dd>
- <dl>
- <dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- compression level. Supported values depend on the library version,
- common values are from 1 to 22.
- </dd></dl>
- </dd><dt>Format 7zip</dt><dd>
- <dl>
- <dt>'''compression'''</dt><dd>
- The value is one of
- "store",
- "deflate",
- "bzip2",
- "lzma1",
- "lzma2"
- or
- "ppmd"
- to indicate how the following entries should be compressed.
- Note that this setting is ignored for directories, symbolic links,
- and other special entries.
- </dd><dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- compression level.
- Values between 0 and 9 are supported.
- The interpretation of the compression level depends on the chosen
- compression method.
- </dd></dl>
- </dd><dt>Format bin</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file names.
- </dd></dl>
- </dd><dt>Format gnutar</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file, group and user names.
- </dd></dl>
- </dd><dt>Format iso9660 - volume metadata</dt><dd>
- These options are used to set standard ISO9660 metadata.
- <dl>
- <dt>'''abstract-file'''=''filename''</dt><dd>
- The file with the specified name will be identified in the ISO9660 metadata
- as holding the abstract for this volume.
- Default: none.
- </dd><dt>'''application-id'''=''filename''</dt><dd>
- The file with the specified name will be identified in the ISO9660 metadata
- as holding the application identifier for this volume.
- Default: none.
- </dd><dt>'''biblio-file'''=''filename''</dt><dd>
- The file with the specified name will be identified in the ISO9660 metadata
- as holding the bibliography for this volume.
- Default: none.
- </dd><dt>'''copyright-file'''=''filename''</dt><dd>
- The file with the specified name will be identified in the ISO9660 metadata
- as holding the copyright for this volume.
- Default: none.
- </dd><dt>'''publisher'''=''filename''</dt><dd>
- The file with the specified name will be identified in the ISO9660 metadata
- as holding the publisher information for this volume.
- Default: none.
- </dd><dt>'''volume-id'''=''string''</dt><dd>
- The specified string will be used as the Volume Identifier in the ISO9660 metadata.
- It is limited to 32 bytes.
- Default: none.
- </dd></dl>
- </dd><dt>Format iso9660 - boot support</dt><dd>
- These options are used to make an ISO9660 image that can be directly
- booted on various systems.
- <dl>
- <dt>'''boot'''=''filename''</dt><dd>
- The file matching this name will be used as the El Torito boot image file.
- </dd><dt>'''boot-catalog'''=''name''</dt><dd>
- The name that will be used for the El Torito boot catalog.
- Default:
- ''boot.catalog''
- </dd><dt>'''boot-info-table'''</dt><dd>
- The boot image file provided by the
- '''boot'''=''filename''
- option will be edited with appropriate boot information in bytes 8 through 64.
- Default: disabled
- </dd><dt>'''boot-load-seg'''=''hexadecimal-number''</dt><dd>
- The load segment for a no-emulation boot image.
- </dd><dt>'''boot-load-size'''=''decimal-number''</dt><dd>
- The number of "virtual" 512-byte sectors to be loaded from a no-emulation boot image.
- Some very old BIOSes can only load very small images, setting this
- value to 4 will often allow such BIOSes to load the first part of
- the boot image (which will then need to be intelligent enough to
- load the rest of itself).
- This should not be needed unless you are trying to support systems with very old BIOSes.
- This defaults to the full size of the image.
- </dd><dt>'''boot-type'''=''value''</dt><dd>
- Specifies the boot semantics used by the El Torito boot image:
- If the
- ''value''
- is
- '''fd''',
- then the boot image is assumed to be a bootable floppy image.
- If the
- ''value''
- is
- '''hd''',
- then the boot image is assumed to be a bootable hard disk image.
- If the
- ''value''
- is
- '''no-emulation''',
- the boot image is used without floppy or hard disk emulation.
- If the boot image is exactly 1.2MB, 1.44MB, or 2.88MB, then
- the default is
- '''fd''',
- otherwise the default is
- '''no-emulation'''.
- </dd></dl>
- </dd><dt>Format iso9660 - filename and size extensions</dt><dd>
- Various extensions to the base ISO9660 format.
- <dl>
- <dt>'''allow-ldots'''</dt><dd>
- If enabled, allows filenames to begin with a leading period.
- If disabled, filenames that begin with a leading period will have
- that period replaced by an underscore character in the standard ISO9660
- namespace.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: disabled.
- </dd><dt>'''allow-lowercase'''</dt><dd>
- If enabled, allows filenames to contain lowercase characters.
- If disabled, filenames will be forced to uppercase.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: disabled.
- </dd><dt>'''allow-multidot'''</dt><dd>
- If enabled, allows filenames to contain multiple period characters, in violation of the ISO9660 specification.
- If disabled, additional periods will be converted to underscore characters.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: disabled.
- </dd><dt>'''allow-period'''</dt><dd>
- If enabled, allows filenames to contain trailing period characters, in violation of the ISO9660 specification.
- If disabled, trailing periods will be converted to underscore characters.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: disabled.
- </dd><dt>'''allow-pvd-lowercase'''</dt><dd>
- If enabled, the Primary Volume Descriptor may contain lowercase ASCII characters, in violation of the ISO9660 specification.
- If disabled, characters will be converted to uppercase ASCII.
- Default: disabled.
- </dd><dt>'''allow-sharp-tilde'''</dt><dd>
- If enabled, sharp and tilde characters will be permitted in filenames, in violation if the ISO9660 specification.
- If disabled, such characters will be converted to underscore characters.
- Default: disabled.
- </dd><dt>'''allow-vernum'''</dt><dd>
- If enabled, version numbers will be included with files.
- If disabled, version numbers will be suppressed, in violation of the ISO9660 standard.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: enabled.
- </dd><dt>'''iso-level'''</dt><dd>
- This enables support for file size and file name extensions in the
- core ISO9660 area.
- The name extensions specified here do not affect the names stored in the Rockridge or Joliet extension areas.
- <dl>
- <dt>'''iso-level=1'''</dt><dd>
- The most compliant form of ISO9660 image.
- Filenames are limited to 8.3 uppercase format,
- directory names are limited to 8 uppercase characters,
- files are limited to 4 GiB,
- the complete ISO9660 image cannot exceed 4 GiB.
- </dd><dt>'''iso-level=2'''</dt><dd>
- Filenames are limited to 30 uppercase characters with a 30-character extension,
- directory names are limited to 30 characters,
- files are limited to 4 GiB.
- </dd><dt>'''iso-level=3'''</dt><dd>
- As with
- '''iso-level=2''',
- except that files may exceed 4 GiB.
- </dd><dt>'''iso-level=4'''</dt><dd>
- As with
- '''iso-level=3''',
- except that filenames may be up to 193 characters
- and may include arbitrary 8-bit characters.
- </dd></dl>
- </dd><dt>'''joliet'''</dt><dd>
- Microsoft's Joliet extensions store a completely separate set of directory information about each file.
- In particular, this information includes Unicode filenames of up to 255 characters.
- Default: enabled.
- </dd><dt>'''limit-depth'''</dt><dd>
- If enabled, libarchive will use directory relocation records to ensure that
- no pathname exceeds the ISO9660 limit of 8 directory levels.
- If disabled, no relocation will occur.
- Default: enabled.
- </dd><dt>'''limit-dirs'''</dt><dd>
- If enabled, libarchive will cause an error if there are more than
- 65536 directories.
- If disabled, there is no limit on the number of directories.
- Default: enabled
- </dd><dt>'''pad'''</dt><dd>
- If enabled, 300 kiB of zero bytes will be appended to the end of the archive.
- Default: enabled
- </dd><dt>'''relaxed-filenames'''</dt><dd>
- If enabled, all 7-bit ASCII characters are permitted in filenames
- (except lowercase characters unless
- '''allow-lowercase'''
- is also specified).
- This violates ISO9660 standards.
- This does not impact names stored in the Rockridge or Joliet extension area.
- Default: disabled.
- </dd><dt>'''rockridge'''</dt><dd>
- The Rockridge extensions store an additional set of POSIX-style file
- information with each file, including mtime, atime, ctime, permissions,
- and long filenames with arbitrary 8-bit characters.
- These extensions also support symbolic links and other POSIX file types.
- Default: enabled.
- </dd></dl>
- </dd><dt>Format iso9660 - zisofs support</dt><dd>
- The zisofs extensions permit each file to be independently compressed
- using a gzip-compatible compression.
- This can provide significant size savings, but requires the reading
- system to have support for these extensions.
- These extensions are disabled by default.
- <dl>
- <dt>'''compression-level'''=number</dt><dd>
- The compression level used by the deflate compressor.
- Ranges from 0 (least effort) to 9 (most effort).
- Default: 6
- </dd><dt>'''zisofs'''</dt><dd>
- Synonym for
- '''zisofs=direct'''.
- </dd><dt>'''zisofs=direct'''</dt><dd>
- Compress each file in the archive.
- Unlike
- '''zisofs=indirect''',
- this is handled entirely within libarchive and does not require a
- separate utility.
- For best results, libarchive tests each file and will store
- the file uncompressed if the compression does not actually save any space.
- In particular, files under 2k will never be compressed.
- Note that boot image files are never compressed.
- </dd><dt>'''zisofs=indirect'''</dt><dd>
- Recognizes files that have already been compressed with the
- '''mkzftree'''
- utility and sets up the necessary file metadata so that
- readers will correctly identify these as zisofs-compressed files.
- </dd><dt>'''zisofs-exclude'''=''filename''</dt><dd>
- Specifies a filename that should not be compressed when using
- '''zisofs=direct'''.
- This option can be provided multiple times to suppress compression
- on many files.
- </dd></dl>
- </dd><dt>Format mtree</dt><dd>
- <dl>
- <dt>'''cksum''', '''device''', '''flags''', '''gid''', '''gname''', '''indent''', '''link''', '''md5''', '''mode''', '''nlink''', '''rmd160''', '''sha1''', '''sha256''', '''sha384''', '''sha512''', '''size''', '''time''', '''uid''', '''uname'''</dt><dd>
- Enable a particular keyword in the mtree output.
- Prefix with an exclamation mark to disable the corresponding keyword.
- The default is equivalent to
- "device, flags, gid, gname, link, mode, nlink, size, time, type, uid, uname".
- </dd><dt>'''all'''</dt><dd>
- Enables all of the above keywords.
- </dd><dt>'''use-set'''</dt><dd>
- Enables generation of
- '''/set'''
- lines that specify default values for the following files and/or directories.
- </dd><dt>'''indent'''</dt><dd>
- XXX needs explanation XXX
- </dd></dl>
- </dd><dt>Format newc</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file names.
- </dd></dl>
- </dd><dt>Format odc</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file names.
- </dd></dl>
- </dd><dt>Format pwb</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file names.
- </dd></dl>
- </dd><dt>Format pax</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file, group and user names.
- The value is one of
- "BINARY"
- or
- "UTF-8".
- With
- "BINARY"
- there is no character conversion, with
- "UTF-8"
- names are converted to UTF-8.
- </dd><dt>'''xattrheader'''</dt><dd>
- When storing extended attributes, this option configures which
- headers should be written. The value is one of
- "all",
- "LIBARCHIVE",
- or
- "SCHILY".
- By default, both
- "LIBARCHIVE.xattr"
- and
- "SCHILY.xattr"
- headers are written.
- </dd></dl>
- </dd><dt>Format ustar</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file, group and user names.
- </dd></dl>
- </dd><dt>Format v7tar</dt><dd>
- <dl>
- <dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file, group and user names.
- </dd></dl>
- </dd><dt>Format warc</dt><dd>
- <dl>
- <dt>'''omit-warcinfo'''</dt><dd>
- Set to
- "true"
- to disable output of the warcinfo record.
- </dd></dl>
- </dd><dt>Format xar</dt><dd>
- <dl>
- <dt>'''checksum'''=''type''</dt><dd>
- Use
- ''type''
- as file checksum method.
- Supported values are
- "none",
- "md5",
- and
- "sha1"
- (default.)
- </dd><dt>'''compression'''=''type''</dt><dd>
- Use
- ''type''
- as compression method.
- Supported values are
- "none",
- "bzip2",
- "gzip"
- (default,)
- "lzma"
- and
- "xz".
- </dd><dt>'''compression_level'''</dt><dd>
- The value is a decimal integer from 1 to 9 specifying the compression level.
- </dd><dt>'''toc-checksum'''=''type''</dt><dd>
- Use
- ''type''
- as table of contents checksum method.
- Supported values are
- "none",
- "md5"
- and
- "sha1"
- (default.)
- </dd></dl>
- </dd><dt>Format zip</dt><dd>
- <dl>
- <dt>'''compression'''</dt><dd>
- The value is either
- "store"
- or
- "deflate"
- to indicate how the following entries should be compressed.
- Note that this setting is ignored for directories, symbolic links,
- and other special entries.
- </dd><dt>'''compression-level'''</dt><dd>
- The value is interpreted as a decimal integer specifying the
- compression level.
- Values between 0 and 9 are supported.
- A compression level of 0 switches the compression method to
- "store",
- other values will enable
- "deflate"
- compression with the given level.
- </dd><dt>'''encryption'''</dt><dd>
- Enable encryption using traditional zip encryption.
- </dd><dt>'''encryption'''=''type''</dt><dd>
- Use
- ''type''
- as encryption type.
- Supported values are
- "zipcrypt"
- (traditional zip encryption,)
- "aes128"
- (WinZip AES-128 encryption)
- and
- "aes256"
- (WinZip AES-256 encryption.)
- </dd><dt>'''experimental'''</dt><dd>
- This boolean option enables or disables experimental Zip features
- that may not be compatible with other Zip implementations.
- </dd><dt>'''fakecrc32'''</dt><dd>
- This boolean option disables CRC calculations.
- All CRC fields are set to zero.
- It should not be used except for testing purposes.
- </dd><dt>'''hdrcharset'''</dt><dd>
- The value is used as a character set name that will be
- used when translating file names.
- </dd><dt>'''zip64'''</dt><dd>
- Zip64 extensions provide additional file size information
- for entries larger than 4 GiB.
- They also provide extended file offset and archive size information
- when archives exceed 4 GiB.
- By default, the Zip writer selectively enables these extensions only as needed.
- In particular, if the file size is unknown, the Zip writer will
- include Zip64 extensions to guard against the possibility that the
- file might be larger than 4 GiB.
- Setting this boolean option will force the writer to use Zip64 extensions
- even for small files that would not otherwise require them.
- This is primarily useful for testing.
- Disabling this option with
- '''!zip64'''
- will force the Zip writer to avoid Zip64 extensions:
- It will reject files with size greater than 4 GiB,
- it will reject any new entries once the total archive size reaches 4 GiB,
- and it will not use Zip64 extensions for files with unknown size.
- In particular, this can improve compatibility when generating archives
- where the entry sizes are not known in advance.
- </dd></dl>
- </dd></dl>
- == EXAMPLES ==
- The following example creates an archive write handle to
- create a gzip-compressed ISO9660 format image.
- The two options here specify that the ISO9660 archive will use
- ''kernel.img''
- as the boot image for El Torito booting, and that the gzip
- compressor should use the maximum compression level.
- ```text
- a = archive_write_new();
- archive_write_add_filter_gzip(a);
- archive_write_set_format_iso9660(a);
- archive_write_set_options(a, "boot=kernel.img,compression=9");
- archive_write_open_filename(a, filename, blocksize);
- ```
- == ERRORS ==
- More detailed error codes and textual descriptions are available from the
- '''archive_errno'''()
- and
- '''archive_error_string'''()
- functions.
- == SEE ALSO ==
- [[ManPageBsdtar1]],
- [[ManPageArchiveReadSetOptions3]],
- [[ManPageArchiveWrite3]],
- [[ManPageLibarchive3]]
- == HISTORY ==
- The
- '''libarchive'''
- library first appeared in
- FreeBSD 5.3.
- == AUTHORS ==
- The options support for libarchive was originally implemented by
- Michihiro NAKAJIMA.
- == BUGS ==
|