SYNOPSIS
use XMLTV::Gunzip;
my $decompressed = gunzip($gzdata);
my $fh = gunzip_open('file.gz') or die;
while (<$fh>) { print }
Compress::Zlib will be used if installed, otherwise an external gzip will be spawned. gunzip() returns the decompressed data and throws an exception if things go wrong; gunzip_open() returns a filehandle, or undef.