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

       Raphaël Hertzog <hertzog@debian.org>.