Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/polka/_.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6637-_.ps) >>/Users/jc/w/tmp/Tune-6637-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/polka/_.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Tune-6637-_.abc 139 ABC music file with the extracted tune(s)
Tune-6637-_.ps 6 PostScript
Tune-6637-_.txt 139 Plain-text file with the extracted tune(s)
Tune-6637-get.log 3885 Log file, useful mostly for debugging
Tune-66370-get.log 3262 Log file, useful mostly for debugging
Tune-66372-get.log 3840 Log file, useful mostly for debugging
Tune-66373-get.log 4490 Log file, useful mostly for debugging
Tune-66375-get.log 5327 Log file, useful mostly for debugging
Tune-66377-get.log 4302 Log file, useful mostly for debugging
These files should be available for 24 hours.