krb5 and thread safety, revisited - do we need callbacks?

[Morrison, Wayne]

...
> So, do we need to provide for the callback registration 
> capability?  Or can we just go ahead and use pthreads on UNIX systems 
> that support it, and whatever the basic Windows thread API is?
...
> How about any non-UNIX systems we might actually care about? 

I don't know if OpenVMS qualifies as a "non-UNIX system that you care
about", but here's my 2 cents worth on the subject.

Support for thread-safe libraries is high on our list of things we'd
like to see in a future release.  We expect that the use of pthreads
will satisfy OpenVMS users - it will certainly be sufficient for our
in-house applications' needs.  We already ship sharable libraries
(sharable images, in OpenVMS terms) in both 32 & 64-bit libraries,
but we've had multiple requests to make them thread-safe.  I'd
much prefer that this happen as part of the standard code base, and
not as OpenVMS-specific changes.

I'm also a firm believer in the KISS principle.  Let's not make this
any more complicated than it needs to be.  I don't see a need to
abstract this to generic thread libraries when there is a standard
available on the vast majority of the platforms that Kerberos runs on.

	Wayne Morrison
	Project Leader, Kerberos & CDSA
	OpenVMS Engineering