Take out my (long since disabled) POSIX signal mask handling code.
I'm not going to have the time or energy to get this working x-platform
-- anyone who does is welcome to the code!
diff --git a/Doc/whatsnew/whatsnew23.tex b/Doc/whatsnew/whatsnew23.tex
index 362db5f..de46869 100644
--- a/Doc/whatsnew/whatsnew23.tex
+++ b/Doc/whatsnew/whatsnew23.tex
@@ -1485,10 +1485,8 @@
location.
\item Support for more advanced POSIX signal handling was added
-to the \module{signal} module by adding the \function{sigpending},
-\function{sigprocmask} and \function{sigsuspend} functions where supported
-by the platform. These functions make it possible to avoid some previously
-unavoidable race conditions with signal handling.
+to the \module{signal} but then removed again as it proved impossible
+to make it work reliably across platforms.
\item The \module{socket} module now supports timeouts. You
can call the \method{settimeout(\var{t})} method on a socket object to