Related bit of behavior:

ben@Tyr:~$ printf "a,b,c,,,"|perl -F, -ane 'print 0+@F, "\n"'
3
ben@Tyr:~$ printf "a,b,c,,,\n"|perl -F, -ane 'print 0+@F, "\n"'
6
[download]

It does seem as though the autosplit takes that '\n' as some sort of a fencepost and counts the fields up to it if it exists, and chops them off otherwise.

-- 
Human history becomes more and more a race between education and catastrophe. -- HG Wells