rc and signals

[arnold@cc.gatech.edu (Arnold Robbins)]

> The more I think about it, the more I don't like the way rc uses signals
> as indicies.  I would rather see it extend sigmsgs to contain rows like
> 	{SIGTERM, "sigterm", "terminated"}
> Then, rather then using a signal as an index, it looped through the table
> to find the matching SIGxxx, and then used the table subscript as the
> index.  It might be possible to generate this table automatically.

Another way to do it would be to generate the table

	#ifdef SIGFOO
		{ SIGFOO, "sigfoo", "murphy came to town"},
	#endif /* SIGFOO */

Then, at startup, sort the table, eliminate duplicates, and voila, the
signal can be used an index again.

The "standard" signals don't need the ifdefs, but there are lots of other
signals that are not universal, and also signals that are often aliased
to each other (e.g. SIGPOLL <-> SIGIO, SIGCLD <-> SIGCHLD. Aren't merged
Unixes wondeful?)

I believe ksh does something along these lines.  For all that ksh may be
bloated as a language, DGK is one smart guy and there's no reason not to
borrow implementation tricks.

Arnold