This is an automated email from the ASF dual-hosted git repository. acassis pushed a commit to branch master in repository https://gitbox.apache.org/repos/asf/nuttx.git
commit 8b4833c3530408d225564752d7400429e1694e53 Author: Marco Casaroli <[email protected]> AuthorDate: Sun Oct 18 17:27:28 2026 +0200 Documentation: An ignored signal does not wake a wait. The signals guide said that any signal wakes a wait with EINTR. Say that a signal that is ignored is discarded and does not wake a wait, so a program must install a handler for a signal that should wake it. Assisted-by: Claude Code:claude-opus-5-5 Signed-off-by: Marco Casaroli <[email protected]> --- Documentation/guides/concurrency/signal_events_interrupt_handlers.rst | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Documentation/guides/concurrency/signal_events_interrupt_handlers.rst b/Documentation/guides/concurrency/signal_events_interrupt_handlers.rst index 9a4f080e4a7..e0611efba8b 100644 --- a/Documentation/guides/concurrency/signal_events_interrupt_handlers.rst +++ b/Documentation/guides/concurrency/signal_events_interrupt_handlers.rst @@ -210,7 +210,9 @@ Signals Signals would work fine too. Signals have a side-effect that is sometimes helpful and sometimes a pain in the butt: They cause almost all kinds of waits (``read()``, ``sem_wait()``, etc.) to wake up and return an error with -``errno=EINTR``. +``errno=EINTR``. A signal that is ignored (that has no action, as +``SIGCHLD`` by default) is discarded and does not wake a wait, as POSIX +requires: a program must install a handler for a signal that should wake it. That is sometimes helpful because you can wake up a ``recv()`` or a ``read()`` etc., detect the event that generated the signal, and do something
