Provided by: libarchive-dev_3.4.0-2ubuntu1.5_amd64 
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
int
archive_write_set_filter_option(struct archive *, const char *module, const char *option,
const char *value);
int
archive_write_set_format_option(struct archive *, const char *module, const char *option,
const char *value);
int
archive_write_set_option(struct archive *, const char *module, const char *option, const char *value);
int
archive_write_set_options(struct archive *, const char *options);
DESCRIPTION
These functions provide a way for libarchive clients to configure specific write modules.
archive_write_set_filter_option(), archive_write_set_format_option()
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.
archive_write_set_option()
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.
archive_write_set_options()
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:
option=value
The option/value pair will be provided to every module. Modules that do not accept an
option with this name will ignore it.
option The option will be provided to every module with a value of “1”.
!option
The option will be provided to every module with a NULL value.
module:option=value, module:option, module:!option
As above, but the corresponding option and value will be provided only to modules whose
name matches module.
OPTIONS
Filter gzip
compression-level
The value is interpreted as a decimal integer specifying the gzip compression level.
Filter xz
compression-level
The value is interpreted as a decimal integer specifying the compression level.
Format mtree
cksum, device, flags, gid, gname, indent, link, md5, mode, nlink, rmd160, sha1, sha256, sha384,
sha512, size, time, uid, uname
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”.
all Enables all of the above keywords.
use-set
Enables generation of /set lines that specify default values for the following files
and/or directories.
indent XXX needs explanation XXX
Format iso9660 - volume metadata
These options are used to set standard ISO9660 metadata.
abstract-file=filename
The file with the specified name will be identified in the ISO9660 metadata as holding
the abstract for this volume. Default: none.
application-id=filename
The file with the specified name will be identified in the ISO9660 metadata as holding
the application identifier for this volume. Default: none.
biblio-file=filename
The file with the specified name will be identified in the ISO9660 metadata as holding
the bibliography for this volume. Default: none.
copyright-file=filename
The file with the specified name will be identified in the ISO9660 metadata as holding
the copyright for this volume. Default: none.
publisher=filename
The file with the specified name will be identified in the ISO9660 metadata as holding
the publisher information for this volume. Default: none.
volume-id=string
The specified string will be used as the Volume Identifier in the ISO9660 metadata. It
is limited to 32 bytes. Default: none.
Format iso9660 - boot support
These options are used to make an ISO9660 image that can be directly booted on various systems.
boot=filename
The file matching this name will be used as the El Torito boot image file.
boot-catalog=name
The name that will be used for the El Torito boot catalog. Default: boot.catalog
boot-info-table
The boot image file provided by the boot=filename option will be edited with appropriate
boot information in bytes 8 through 64. Default: disabled
boot-load-seg=hexadecimal-number
The load segment for a no-emulation boot image.
boot-load-size=decimal-number
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.
boot-type=value
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.
Format iso9660 - filename and size extensions
Various extensions to the base ISO9660 format.
allow-ldots
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.
allow-lowercase
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.
allow-multidot
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.
allow-period
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.
allow-pvd-lowercase
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.
allow-sharp-tilde
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.
allow-vernum
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.
iso-level
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.
iso-level=1
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.
iso-level=2
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.
iso-level=3
As with iso-level=2, except that files may exceed 4 GiB.
iso-level=4
As with iso-level=3, except that filenames may be up to 193 characters and may
include arbitrary 8-bit characters.
joliet 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.
limit-depth
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.
limit-dirs
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
pad If enabled, 300 kiB of zero bytes will be appended to the end of the archive. Default:
enabled
relaxed-filenames
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.
rockridge
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.
Format iso9660 - zisofs support
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.
compression-level=number
The compression level used by the deflate compressor. Ranges from 0 (least effort) to 9
(most effort). Default: 6
zisofs Synonym for zisofs=direct.
zisofs=direct
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.
zisofs=indirect
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.
zisofs-exclude=filename
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.
Format 7zip
compression
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.
compression-level
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.
Format zip
compression
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.
compression-level
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.
experimental
This boolean option enables or disables experimental Zip features that may not be
compatible with other Zip implementations.
fakecrc32
This boolean option disables CRC calculations. All CRC fields are set to zero. It
should not be used except for testing purposes.
hdrcharset
This sets the character set used for filenames.
zip64 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.
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.
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
tar(1), libarchive(3), archive_read_set_options(3), archive_write(3)
HISTORY
The libarchive library first appeared in FreeBSD 5.3.
AUTHORS
The options support for libarchive was originally implemented by Michihiro NAKAJIMA.
BUGS
Debian July 27, 2019 ARCHIVE_WRITE_OPTIONS(3)