Use the "piped" form of open(). Untested code: 
# Old-style: Bareword filehandles and two-arg opens:
open IN,  "zcat $in_filename|"         or die;
open OUT, "|gzip -c - > $out_filename" or die;

# New style: Lexical filehandles and three-arg opens
open my $in_fh,  '-|', "zcat $in_filename"         or die;
open my $out_fh, '|-', "gzip -c - > $out_filename" or die;

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See also "Using open() for IPC" in perlipc.

In reply to Re: reading compressed data by Util
in thread reading compressed data by kettle

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