#!/usr/local/bin/perl

use strict ;
use warnings ;

use Compress::Zlib ;

die "Usage: gzgrep pattern file...\n"
    unless @ARGV >= 2;

my $pattern = shift ;

my $file ;

foreach $file (@ARGV) {
    my $gz = gzopen($file, "rb") 
         or die "Cannot open $file: $gzerrno\n" ;

    while ($gz->gzreadline($_) > 0) {
        print if /$pattern/ ;
    }

    die "Error reading from $file: $gzerrno\n" 
        if $gzerrno != Z_STREAM_END ;
    
    $gz->gzclose() ;
}