Dpkg::Compression::Process(3) libdpkg-perl Dpkg::Compression::Process(3)NAME
Dpkg::Compression::Process - run compression/decompression processes
DESCRIPTION
This module provides an object oriented interface to run and manage compression/decompression processes.
METHODS
my $proc = Dpkg::Compression::Process->new(%opts)
Create a new instance of the object. Supported options are "compression" and "compression_level" (see corresponding set_* functions).
$proc->set_compression($comp)
Select the compression method to use. It errors out if the method is not supported according to "compression_is_supported" (of
Dpkg::Compression).
$proc->set_compression_level($level)
Select the compression level to use. It errors out if the level is not valid according to "compression_is_valid_level" (of
Dpkg::Compression).
my @exec = $proc->get_compress_cmdline()
my @exec = $proc->get_uncompress_cmdline()
Returns a list ready to be passed to "exec", its first element is the program name (either for compression or decompression) and the
following elements are parameters for the program.
When executed the program acts as a filter between its standard input and its standard output.
$proc->compress(%opts)
Starts a compressor program. You must indicate where it will read its uncompressed data from and where it will write its compressed
data to. This is accomplished by passing one parameter "to_*" and one parameter "from_*" as accepted by Dpkg::IPC::spawn.
You must call "wait_end_process" after having called this method to properly close the sub-process (and verify that it exited without
error).
$proc->uncompress(%opts)
Starts a decompressor program. You must indicate where it will read its compressed data from and where it will write its uncompressed
data to. This is accomplished by passing one parameter "to_*" and one parameter "from_*" as accepted by Dpkg::IPC::spawn.
You must call "wait_end_process" after having called this method to properly close the sub-process (and verify that it exited without
error).
$proc->wait_end_process(%opts)
Call Dpkg::IPC::wait_child to wait until the sub-process has exited and verify its return code. Any given option will be forwarded to
the "wait_child" function. Most notably you can use the "nocheck" option to verify the return code yourself instead of letting
"wait_child" do it for you.
AUTHOR
Raphael Hertzog <hertzog@debian.org>.
1.16.0.3 2012-04-17 Dpkg::Compression::Process(3)
Check Out this Related Man Page
Dpkg::Compression(3) libdpkg-perl Dpkg::Compression(3)NAME
Dpkg::Compression - simple database of available compression methods
DESCRIPTION
This modules provides a few public funcions and a public regex to interact with the set of supported compression methods.
EXPORTED VARIABLES
$compression_re_file_ext
A regex that matches a file extension of a file compressed with one of the supported compression methods.
EXPORTED FUNCTIONS
my @list = compression_get_list()
Returns a list of supported compression methods (sorted alphabetically).
compression_is_supported($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.
my $comp = compression_get_default()
Return the default compression method. It's "gzip" unless "compression_set_default" has been used to change it.
compression_set_default($comp)
Change the default compression method. Errors out if the given compression method is not supported.
my $level = compression_get_default_level()
Return the default compression level used when compressing data. It's "9" for "gzip" and "bzip2", "6" for "xz" and "lzma", unless
"compression_set_default_level" has been used to change it.
compression_set_default_level($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")
AUTHOR
Raphael Hertzog <hertzog@debian.org>.
1.16.15 2014-06-05 Dpkg::Compression(3)