As long as you're willing to try out non-core modules (even though you might have limited ability to install them), you should actually try PerlIO::gzip -- it implements gzip compression and uncompression as a PerlIO layer, so you can do things like: 
use PerlIO::gzip;

open( ICMP, "<:gzip", "sometext.gz" );
open( OCMP, ">:gzip", "chosenlines.gz" );
while (<ICMP>) {
    print OCMP if /something matches/;
}
close OCMP;

[download]
In other words, this creates an i/o layer that handles the compression for you, on input, output or both, and you just handle the data as if compression were not a factor.

I can't wait for this to be part of the core distro.

(update: corrected the spelling on the cpan link)

UPDATE: (2010-10-18) It seems that PerlIO::gzip should be viewed as superseded by PerlIO::via:gzip. (see PerlIO::gzip or PerlIO::via::gzip).

In reply to Re: dynamic zcat and grep by graff
in thread dynamic zcat and grep by clmcshque

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