Dpkg::Compression.3perl - Man Page

simple database of available compression methods


This modules provides a few public functions and a public regex to interact with the set of supported compression methods.


@list = compression_get_list()

Returns a list of supported compression methods (sorted alphabetically).


Returns a boolean indicating whether the give compression method is known and supported.

compression_get_property($comp, $property)

Returns the requested property of the compression method. Returns undef if either the property or the compression method doesn't exist. Valid properties currently include “file_ext” for the file extension, “default_level” for the default compression level, “comp_prog” for the name of the compression program and “decomp_prog” for the name of the decompression program.


Returns the compression method that is likely used on the indicated filename based on its file extension.

$regex = compression_get_file_extension_regex()

Returns a regex that matches a file extension of a file compressed with one of the supported compression methods.

$comp = compression_get_default()

Return the default compression method. It is “xz” unless compression_set_default has been used to change it.


Change the default compression method. Errors out if the given compression method is not supported.

$level = compression_get_default_level()

Return the default compression level used when compressing data. It's “9” for “gzip” and “bzip2”, “6” for “xz” and “lzma”, unless compression_set_default_level has been used to change it.


Change the default compression level. Passing undef as the level will reset it to the compressor specific default, otherwise errors out if the level is not valid (see compression_is_valid_level).


Returns a boolean indicating whether $level is a valid compression level (it must be either a number between 1 and 9 or “fast” or “best”)


Version 2.00 (dpkg 1.20.0)

Hide variables: $default_compression, $default_compression_level and $compression_re_file_ext.

Version 1.02 (dpkg 1.17.2)

New function: compression_get_file_extension_regex()

Deprecated variables: $default_compression, $default_compression_level and $compression_re_file_ext

Version 1.01 (dpkg 1.16.1)

Default compression level is not global any more, it is per compressor type.

Version 1.00 (dpkg 1.15.6)

Mark the module as public.


2021-07-21 1.20.9 libdpkg-perl