Dpkg::Compression(3)

NAME
Dpkg::Compression - simple database of available compression methods

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

FUNCTIONS

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

compression_is_supported($comp)
    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.

compression_guess_from_filename($filename)
    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.

compression_set_default($comp)
    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.

compression_set_default_level($level)
    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").

compression_is_valid_level($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")

CHANGES

  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.

AUTHOR
Raphaël Hertzog <hertzog@debian.org>.