signalfd and thread semantics

[Michael Kerrisk]

Hi Davide,

Working on the signalfd man page, another question comes up:

What are the intended semantics for a signalfd file descriptor with respect
to threads?  I have not yet tested the behavior, but in any case, I better
check what is expected.

A signal can be directed to the process as a whole (e.g., using kill(2)),
or to a particular thread (using, e.g., pthread_kill(2), or tgkill(2)).

So that raises the question: If a thread calls signalfd(), does the
resulting file descriptor return just those signals directed to [the thread
and the process as a whole], or will it also receive signals that are
targeted at other threads in the process?  I would hope the former is the
case, but I'm not sure what has been implemented (or intended).

Cheers,

Michael

-- 
Michael Kerrisk
maintainer of Linux man pages Sections 2, 3, 4, 5, and 7

Want to help with man page maintenance?  Grab the latest tarball at
http://www.kernel.org/pub/linux/docs/manpages/
read the HOWTOHELP file and grep the source files for 'FIXME'.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/