pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-50862-4121.ps) >>/Users/jc/w/tmp/Tune-50862-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Gow/CR/4121=Thro_the_wood_Laddie.abc2.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-50862-4121.abc 1569 ABC music file with the extracted tune(s)
Tune-50862-4121.ps 50158 PostScript
Tune-50862-4121.txt 1569 Plain-text file with the extracted tune(s)
Tune-50862-get.log 5785 Log file, useful mostly for debugging
These files should be available for 24 hours.