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
Raphal Hertzog <hertzog@debian.org>.