Well I know I'm confused. Here is a test case that will show my problem. When this is run as a cgi script, the browser will wait until the child exits before finishing. If I comment out the two Spreadsheet modules it works perfectly and finishes without waiting on the child process.

use strict;
go();
    
sub go
{   
    $| = 1;
    $SIG{CHLD} = 'IGNORE';
    close STDIN;
    my $pid = fork;
    if (!defined($pid)) {
        print "Content-type: text/plain\n\n";
        print "Could not fork!\n";
        exit; 
    } elsif ($pid) {
        print "Content-type: text/plain\n\n";
        print "PARENT = $$, KID = $pid\n" . localtime(time);
        close STDERR;
        close STDOUT;
        close STDIN;
        exit;
    } else {
        close STDIN;
        close STDOUT;
        close STDERR;
        use Spreadsheet::ParseExcel;
        use Spreadsheet::WriteExcel;
        open(STDERR, ">test.err");
        sleep(10);
        open(OUT,">>test") or die();
        print OUT "\nKID(me) = $$ " . localtime(time);
        close OUT;
        exit;
    }
}
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