open my $fh, 'uuu.txt';
open my $gh, '| bzip2 -9 -c > /tmp/uuu.txt.bz2'; # or gzip if no bzip2
while (<$fh>) {
    s/\s+//g;
    print $gh $_ or suffer();
}
close $fh;
close $gh or suffer();
system 'bunzip2 -c /tmp/uuu.txt.bz2 > uuu.txt';
unlink '/tmp/uuu.txt.bz2';

sub suffer {
   warn "$!: /tmp/uuu.txt.bz2\n"; # e.g. $! reports disk full
   unlink '/tmp/uuu.txt.bz2';
   exit 256;
}