archive_write_set_filter_option
,
archive_write_set_format_option
,
archive_write_set_option
,
archive_write_set_options
—
functions controlling options for writing
archives
Streaming Archive Library (libarchive, -larchive)
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);
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.
- Filter b64encode
-
mode
- The value is interpreted as octal digits specifying the file
mode.
name
- The value specifies the file name.
- Filter bzip2
-
compression-level
- The value is interpreted as a decimal integer specifying the bzip2
compression level. Supported values are from 1 to 9.
- Filter gzip
-
compression-level
- The value is interpreted as a decimal integer specifying the gzip
compression level. Supported values are from 0 to 9.
timestamp
- Store timestamp. This is enabled by default.
- Filter lrzip
-
compression
=type
- Use type as compression method. Supported values
are “bzip2”, “gzipi”, “lzo”
(ultra fast), and “zpaq” (best, extremely slow).
compression-level
- The value is interpreted as a decimal integer specifying the lrzip
compression level. Supported values are from 1 to 9.
- Filter lz4
-
compression-level
- The value is interpreted as a decimal integer specifying the lz4
compression level. Supported values are from 0 to 9.
stream-checksum
- Enable stream checksum. This is enabled by default.
block-checksum
- Enable block checksum. This is disabled by default.
block-size
- The value is interpreted as a decimal integer specifying the lz4
compression block size. Supported values are from 4 to 7
(default).
block-dependence
- Use the previous block of the block being compressed for a compression
dictionary to improve compression ratio. This is disabled by
default.
- Filter lzop
-
compression-level
- The value is interpreted as a decimal integer specifying the lzop
compression level. Supported values are from 1 to 9.
- Filter uuencode
-
mode
- The value is interpreted as octal digits specifying the file
mode.
name
- The value specifies the file name.
- Filter xz
-
compression-level
- The value is interpreted as a decimal integer specifying the
compression level. Supported values are from 0 to 9.
threads
- 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
().
- Filter zstd
-
compression-level
- 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.
long
- Enables long distance matching. The value is interpreted as a decimal
integer specifying log2 window size in bytes. Values from 10 to 30 for
32 bit, or 31 for 64 bit, are supported.
threads
- The value is interpreted as a decimal integer specifying the number of
threads for multi-threaded zstd compression. If set to 0, zstd will
attempt to detect and use the number of physical CPU cores.
- Format 7zip
-
compression
- The value is one of “store”, “copy”,
“deflate”, “bzip2”, “lzma1”,
“lzma2” or “ppmd” to indicate how the
following entries should be compressed. The values
“store” and “copy” are synonyms. 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, with the
exception of bzip2 which only supports values between 1 and 9. The
interpretation of the compression level depends on the chosen
compression method.
- Format bin
-
hdrcharset
- The value is used as a character set name that will be used when
translating file names.
- Format gnutar
-
hdrcharset
- The value is used as a character set name that will be used when
translating file, group and user names.
- 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 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 newc
-
hdrcharset
- The value is used as a character set name that will be used when
translating file names.
- Format odc
-
hdrcharset
- The value is used as a character set name that will be used when
translating file names.
- Format pwb
-
hdrcharset
- The value is used as a character set name that will be used when
translating file names.
- Format pax
-
hdrcharset
- 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.
- 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.
- Format ustar
-
hdrcharset
- The value is used as a character set name that will be used when
translating file, group and user names.
- Format v7tar
-
hdrcharset
- The value is used as a character set name that will be used when
translating file, group and user names.
- Format warc
-
omit-warcinfo
- Set to “true” to disable output of the warcinfo
record.
- Format xar
-
checksum
=type
- Use type as file checksum method. Supported
values are “none”, “md5”, and
“sha1” (default).
compression
=type
- Use type as compression method. Supported values
are “none”, “bzip2”, “gzip”
(default), “lzma” and “xz”.
compression_level
- The value is a decimal integer from 1 to 9 specifying the compression
level.
toc-checksum
=type
- Use type as table of contents checksum method.
Supported values are “none”, “md5” and
“sha1” (default).
- 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.
encryption
- Enable encryption using traditional zip encryption.
encryption
=type
- Use type as encryption type. Supported values
are “zipcrypt” (traditional zip encryption),
“aes128” (WinZip AES-128 encryption) and
“aes256” (WinZip AES-256 encryption).
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
- The value is used as a character set name that will be used when
translating file names.
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.
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);
More detailed error codes and textual descriptions are available
from the archive_errno
() and
archive_error_string
() functions.
The libarchive
library first appeared in
FreeBSD 5.3.
The options support for libarchive was originally implemented by
Michihiro NAKAJIMA.