siglongjmp not async-signal-safe?

From: Marc Rochkind (rochkind@basepath.com)
Date: 04/22/03 

From: "Marc Rochkind" <rochkind@basepath.com>
Date: Tue, 22 Apr 2003 13:43:51 -0600

According to the SUS v3, there are only 116 async-signal-safe functions that
are safe to call from a signal handler that may have interrupted an unsafe
function. Alas, siglongjmp and longjmp are not on the list. So, which shall
I conclude:

1. The SUS is mistaken.
2. They are not safe and should not be used for that reason.
3. The whole issue of async-signal-safety is besides the point when you're
long-jumping. (If this is true, I believe #1 is also true, as the SUS
doesn't discuss this possibility.)

--Marc