From 8ed97a8d543b9596166c670212265dabc44aa3d5 Mon Sep 17 00:00:00 2001 From: Philipp Stephani Date: Tue, 19 Jan 2021 21:35:06 +0100 Subject: [PATCH] Make child signal read pipe non-blocking. Otherwise Emacs might hang when trying to read the pipe twice in a row. This is consistent with the other file descriptors we pass to 'pselect'. * src/process.c (child_signal_init): Make read end of pipe non-blocking. --- src/process.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/process.c b/src/process.c index 09f87908a45..57105982c15 100644 --- a/src/process.c +++ b/src/process.c @@ -7179,6 +7179,8 @@ child_signal_init (void) exits. */ eassert (0 <= fds[0]); eassert (0 <= fds[1]); + if (fcntl (fds[0], F_SETFL, O_NONBLOCK) != 0) + emacs_perror ("fcntl"); add_read_fd (fds[0], child_signal_read, NULL); fd_callback_info[fds[0]].flags &= ~KEYBOARD_FD; child_signal_read_fd = fds[0]; -- 2.39.5