pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-41639-20192_.ps) >>/Users/jc/w/tmp/Tune-41639-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/EliasHowe/MusiciansCompanionP2/20192_.abc

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Tune-41639-20192_.abc 33 ABC music file with the extracted tune(s)
Tune-41639-20192_.ps 6 PostScript
Tune-41639-20192_.txt 33 Plain-text file with the extracted tune(s)
Tune-41639-get.log 9561 Log file, useful mostly for debugging
These files should be available for 24 hours.