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
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,
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 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.
- 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