pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-70730-Londonderry_Air.ps) >>/Users/jc/w/tmp/Tune-70730-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/Ireland/Londonderry_Air.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-70730-Londonderry_Air.abc 3028 ABC music file with the extracted tune(s)
Tune-70730-Londonderry_Air.ps 58259 PostScript
Tune-70730-Londonderry_Air.txt 3028 Plain-text file with the extracted tune(s)
Tune-70730-get.log 7756 Log file, useful mostly for debugging
These files should be available for 24 hours.