[Bug] kill -l 0 outputs T, not EXIT

[Martijn Dekker]

The command

        kill -l 0
outputs T. I would expect EXIT as T is not a valid signal or
pseudosignal name. Since T is the last letter of EXIT, I suspect a typo
somewhere.

AT&T ksh93 outputs EXIT. pdksh/mksh and zsh output 0 (presumably EXIT is
not a real signal). dash and yash give a "no such signal number" error.
All of these seem sensible, but "T" does not.

Confirmed in bash 2.05b.13, 3.2.57 and 4.4.0.

Thanks,

- M.