On Wed, 14 Aug 2019 15:49:00 +0200 Corinna Vinschen wrote: > The only reason I can see is if sigwait_common() returns EINTR because > it was interrupted by an unrelated signal. This in turn lets the read() > call fail with EINTR and that should be expected by the callers, in > theory.
Strangely, this problem also disappears with this patch. diff --git a/winsup/cygwin/select.cc b/winsup/cygwin/select.cc index 9cf892801..82ac0674f 100644 --- a/winsup/cygwin/select.cc +++ b/winsup/cygwin/select.cc @@ -1869,7 +1869,7 @@ thread_signalfd (void *arg) switch (WaitForSingleObject (si->evt, INFINITE)) { case WAIT_OBJECT_0: - tls->signalfd_select_wait = NULL; + //tls->signalfd_select_wait = NULL; event = true; break; default: Moreover, this EINTR is not set by sigwait_common() but set by select_stuff::wait(). With following debug print, the message shows: 1 [main] script 1082 select_stuff::wait: signal = 20 script: poll failed: Interrupted system call Script done, file is typescript however, the signal 20 (SIGCHLD) is registered to signalfd by script and should be caught. diff --git a/winsup/cygwin/select.cc b/winsup/cygwin/select.cc index 9cf892801..adcc75ad3 100644 --- a/winsup/cygwin/select.cc +++ b/winsup/cygwin/select.cc @@ -446,6 +446,7 @@ next_while:; unconditionally, ignoring any SA_RESTART detection by call_signal_handler(). */ _my_tls.call_signal_handler (); + system_printf ("signal = %d\n", _my_tls.infodata.si_signo); set_sig_errno (EINTR); res = select_signalled; /* Cause loop exit in cygwin_select */ break; -- Takashi Yano <takashi.y...@nifty.ne.jp> -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple