pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-56824-Aird_vol4_abc1.ps) >>/Users/jc/w/tmp/Tune-56824-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Aird/Aird_vol4_abc1.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_56824.log 457010 Log file, useful mostly for debugging
Tune-56824-Aird_vol4_abc1.abc 74080 ABC music file with the extracted tune(s)
Tune-56824-Aird_vol4_abc1.ps 1035245 PostScript
Tune-56824-Aird_vol4_abc1.txt 74080 Plain-text file with the extracted tune(s)
Tune-56824-get.log 114751 Log file, useful mostly for debugging
These files should be available for 24 hours.