sub open_file_harder { my ($filename) = @_; return if not defined $filename; if ( my ($extension) = $filename =~ /(\.[^.]+)\z/mx ) { my @readers = ( [ qr/\.t(?:ar\.)?gz\z/ => qw( gzcat ), $filename ], [ qr/\.zip\z/, => qw( unzip -p ), $filename ], [ qr/\.Z\z/ => qw( zcat ), $filename ], [ qr/\.gz\z/ => qw( gzcat ), $filename ], [ qr/\.bz2\z/ => qw( bzcat ), $filename ], ); for my $reader (@readers) { my ( $pattern, @command ) = @{$reader}; if ( $extension =~ $pattern ) { open3( undef, my $fh, undef, @command ); return $fh; } } } open my $fh, '<', $filename or die "Couldn't open $filename: $!"; return $fh; }