2nd bug fix for regexp(3), in regsub()

[sources-request at panda.UUCP]

Mod.sources:  Volume 4, Issue 33
Submitted by: genrad!decvax!utzoo!henry

I cringe with embarrassment!  Another bug in regexp!  In regsub.c, the
following line (line 72 in the original distribution):

	if (*(dst-1) == '\0') {        /* strncpy hit NUL. */

should read

	if (len != 0 && *(dst-1) == '\0') {	/* strncpy hit NUL. */

This shows up as an occasional spurious complaint from regsub about
"damaged match string"... *if* the program invoking it, and the compiler
compiling it, happen to interact just right.  It didn't show in any of
my tests because mine don't.

My thanks to H}vard Eidnes for finding this.

				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry