Some win32 systems (mostly those using Kaspersky, it would seem)
prevent us from faking socketpair(). This makes our signal
notification code just not work. Our response since 1.4 has been to
assert. For users who would rather work without signals than not work
at all, this has been a regression from 1.3e.
This patch makes adding signal events fail in this case; there's no
reason to kill the whole process.
svn:r1303
a) this is 2009
b) niels and nick have been comaintainers for a while
c) saying "all rights reserved" when you then go on to explicitly
disclaim some rights is sheer cargo-cultism.
svn:r1065
