Add a test case for a deadlock.

The CGO_ENABLED=0 failure mode is discussed in:

  https://github.com/golang/go/issues/50113

At the present time, this only passes when the psx package is compiled
CGO_ENABLED=1. The problem being that a blocking read cannot be
interrupted by the CGO_ENABLED=0 build of package "psx". It does not
deadlock when compiled CGO_ENABLED=1 because the psx signal wakes the
reading thread up back into user space.

Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
3 files changed