The XBM this program makes is obviously valid in some sense, but ImageMagick doesn't like it (nor does NetPBM). To fix that, write_xbm needs tweaking to replace this: 
        $fh->say("static unsigned char ${indexed_name}_bits[] = { " . 
+join(', ', $hexes->@*) . ' };');

[download]
with: 
        $fh->say("static unsigned char ${indexed_name}_bits[] = {");
        $fh->say(join(', ', $hexes->@*));
        $fh->say('};');

[download]

In reply to Re: Creating X BitMap (XBM) images with directional gradients by etj
in thread Creating X BitMap (XBM) images with directional gradients by kcott

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