Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/abc1/blank.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4546-blank.ps) >>/Users/jc/w/tmp/Tune-4546-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/abc1/blank.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-4546-blank.abc 142 ABC music file with the extracted tune(s)
Tune-4546-blank.ps 6 PostScript
Tune-4546-blank.txt 142 Plain-text file with the extracted tune(s)
Tune-4546-get.log 12527 Log file, useful mostly for debugging
Tune-45460-get.log 5449 Log file, useful mostly for debugging
Tune-45461-get.log 9966 Log file, useful mostly for debugging
Tune-45462-get.log 4049 Log file, useful mostly for debugging
Tune-45463-get.log 15068 Log file, useful mostly for debugging
Tune-45465-get.log 16455 Log file, useful mostly for debugging
Tune-45466-get.log 8681 Log file, useful mostly for debugging
Tune-45467-get.log 6233 Log file, useful mostly for debugging
Tune-45468-get.log 1295 Log file, useful mostly for debugging
Tune-45469-get.log 3300 Log file, useful mostly for debugging
These files should be available for 24 hours.