kill and sh were merged so that the shell (for trap -l) and
kill (for kill -l) can use the same routine, and site that function
in the shell, rather than in kill (use the code that is in kill as
the basis for that routine). This allows access to sh internals,
and in particular to the posix option, so the builtin kill can
operate in posix mode where the standard requires just a single
character (space of newline) between successive signal names (and
we prefer nicely aligned columns instead)..
In a SMALL shell, use the ancient sh printsignals routine instead,
it is smaller (and very much dumber).
/bin/kill still uses the routine that is in its source, and is
not posix compliant. A task for some other day...
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