use Compress::Zlib;
use strict;
foreach my $f ( grep { -f } @ARGV ){
    my ($buffer,$gz);
    if ($f=~/gz$/){
    (my $rtf = $f) =~ s/(.)gz$//;
    open OOT, ">$rtf" or die "$0:$rtf:$!";    
    binmode OOT;    
    $gz = gzopen($f, "rb") or die "$0:$gzerrno:$!";
    print OOT $buffer while $gz->gzread($buffer) > 0;
    die "$f: $gzerrno:$!" if $gzerrno != Z_STREAM_END;
    $gz->gzclose();
    close(OOT);
    } else { # gzip our file
    open COOT, "$f" or die "$0:$f:$!";
    binmode COOT;
    $gz = gzopen("$f.gz", "wb") 
        or die "$0:$gzerrno:$!";
    while (<COOT>){
        $gz->gzwrite($_) or die "$f.gz,$gzerrno:$!";
    }
    $gz->gzclose;
    }
}
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