It can only happen on resource exhaustion, which is an unlikely situation. That's probably why we didn't handle this case. But let's do it now. This necessitated that qt_create_pipe() return with errno/GetLastError() properly set, so save it and restore around functions that may change it (like qErrnoWarning()). Drive-by update of some warning messages. Testing this is not practical and is fragile, because it requires causing the resource exhaustion problem. Pick-to: 6.6 6.7 Change-Id: I76ffba14ece04f24b43efffd17aafe4f11f54c21 Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de> Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>