Re: gftp, X & cthread problems

[Roland McGrath <roland@frob.com>]

I really do not recommend attempting to port programs that use pthreads to
use cthreads directly instead.  Some programs use thread support only in
simple ways; often such programs have a simple portability layer of their
own that can use pthreads or various other things, and programs whose use
of thread support is already portable to disparate systems are reasonably
likely to use only the simple features.  In those cases it may be easy to
port to cthreads.

But in the general case, it is reasonable nowadays for programs to be
written to the 1003.1-1996 pthreads interface and expect that to be
portable.  Unfortunately, cthreads just lacks a great deal of the
functionality of pthreads.  Some operations do have Hurd-specific
equivalents, but many do not; moreover, the Hurd additions to cthreads that
do exist are not very well-specified, and the details of behavior differ
subtly from pthreads.  In short, I do not suggest using these interfaces,
or cthreads particularly at all, outside of the Hurd's own source code.
(Naturally, if you really know what you are doing and a cthreads port works
in your case, then go ahead.  But if you are going to be looking here for
guidance on the details, then the advice from here is just to avoid it.)