From: Philipp Stephani <phst@google.com>
Date: Sat, 23 Jan 2021 17:39:20 +0000 (+0100)
Subject: Add a FIXME comment to improve the SIGCHLD race condition handling.
X-Git-Tag: emacs-28.0.90~4141
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=59e9ec72442d264a3e08c9886ad3b49fa8dc9f37;p=emacs.git

Add a FIXME comment to improve the SIGCHLD race condition handling.

* src/process.c: Add FIXME comment describing how we could avoid the
self-pipe on modern Unix-like systems.
---

diff --git a/src/process.c b/src/process.c
index 9b1de19f0ae..8abdcd4f0c1 100644
--- a/src/process.c
+++ b/src/process.c
@@ -7164,6 +7164,11 @@ process has been transmitted to the serial port.  */)
    because that emulation delays the delivery of the simulated SIGCHLD
    until all the output from the subprocess has been consumed.  */
 
+/* FIXME: On Unix-like systems that have a proper 'pselect'
+   (HAVE_PSELECT), we should block SIGCHLD in
+   'wait_reading_process_output' and pass a non-NULL signal mask to
+   'pselect' to avoid the need for the self-pipe.  */
+
 /* Set up `child_signal_read_fd' and `child_signal_write_fd'.  */
 
 static void