pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-5491-SwallowtailJig.ps) >>/Users/jc/w/tmp/Tune-5491-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/Contra/SwallowtailJig.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Coll_54918.log 323670 Log file, useful mostly for debugging
Form_54916.log 1185 Log file, useful mostly for debugging
Tune-5491-SwallowtailJig.abc 1558 ABC music file with the extracted tune(s)
Tune-5491-SwallowtailJig.ps 41708 PostScript
Tune-5491-SwallowtailJig.txt 1558 Plain-text file with the extracted tune(s)
Tune-5491-get.log 10690 Log file, useful mostly for debugging
Tune-54916-get.log 11291 Log file, useful mostly for debugging
These files should be available for 24 hours.