capture_output fails with gui

[Mark Tilford]

My program uses the "capture_output" function (shown below) to capture
all text printed to STDOUT.
The program runs fine when I run it from the command prompt, or when I
compile it with PAR as a term app, but when I compile it as a GUI app,
it seems to freeze somewhere it the call to capture_output.  Any idea
how to fix it?



# capture_output by tmoertel http://www.perlmonks.org/?node_id=398709
sub capture_output {

    my $target_fh = shift;
    my $temp_fh = tempfile();
    my $temp_fd = fileno $temp_fh;

    local *SAVED;
    local *TARGET = $target_fh;
    open SAVED, ">&TARGET" or die "can't remember target";
    open TARGET, ">&=$temp_fd" or die "can\'t redirect target";
    my $saved_fh = *SAVED;

    return sub {
        seek $temp_fh, 0, 0 or die "can't seek"; # rewind
        my $captured_output = do {local $/; <$temp_fh> };
        close $temp_fh or die "can't close temp file handle";
        local (*SAVED, *TARGET) = ($saved_fh, $target_fh);
        open TARGET, ">&SAVED" or die "can't restore target";
        close SAVED or die "can't close SAVED";
        return $captured_output;
    }
}