* src/time.cxx (alarm_action): Added call to cyg_posix_signal_sigwait() to wake up any sigwait()ing threads. * src/signal.cxx (cyg_posix_signal_sigwait): Added this function to export access to signal_sigwait conditional variable. (sigtimedwait): Added call to cyg_posix_timer_asr() to allow timer signals to be delivered here. * src/pprivate.h: Added prototype for cyg_posix_signal_sigwait(). * cdl/posix.cdl: * tests/signal3.c: Added this program to test interaction of timers and signals, particularly sigwait(). Based on a test program from N.Suresh <nsuresh@cdotb.ernet.in>.