pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-83678-164.ps) >>/Users/jc/w/tmp/Tune-83678-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/mirror/www.leeds.ac.uk/petrie/abc/164.abc

Error exit status 256; here are some files to check:
[P=get.cgi V=1/1 B=0 scale=0.60 512x512 PNG]
filesizedescription
Tune-83678-164.abc 82 ABC music file with the extracted tune(s)
Tune-83678-164.ps 31320 PostScript
Tune-83678-164.txt 82 Plain-text file with the extracted tune(s)
Tune-83678-get.log 4336 Log file, useful mostly for debugging
These files should be available for 24 hours.