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¶