I doubt that the @files Array is exhausted. So most likely it is my some stuff that is causing the problem. (This is not in a CGI environment. Just a straight script.)

I'm guessing that this is the offending line.

open2(\*GZIP_IN, \*GZIP_OUT, "$gzip -dc -q $outfile$$") or die "cannot
+ open2 $gzip: $!";
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Again, this should only be one fork (for the one file that gzip is acting upon). At least I think it should be just one fork. (Obviously it isn't. :) )

Opening a pipe both from and to "gzip -dc" ? Perhaps if you are doing line-mode input from the compressed source, that's the problem:

while (<WHEREEVERTHECOMPRESSEDDATAIS>) {
    # $_ could be potentially huge, if it doesn't 
    # contain a newline somewhere soon
    print GZIP_IN;
}
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See read() or sysread() if that's it. But then, that's just a guess...good luck.