From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon-590EEB7GvNiWaY/ihj7yzEB+6BGkLq7r@public.gmane.org Subject: [Bug 95331] fcntl.2 + sigaction.2 + signal.7 need further information about use of a SA_SIGINFO signal handler that uses si->si_fd Date: Mon, 23 Mar 2015 19:58:30 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-man@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=95331 --- Comment #1 from Jason Vas Dias --- To test (under kernel 3.13, Linux x86_64 8-core) $ gcc -g -pthread -o t_sigio_rdwr t_sigio_rdwr.c $ mkfifo -m 0600 /tmp/f.in /tmp/f.out $ strace -f bash -c './t_sigio_rdwr /tmp/f.out' & ... $ echo 'hello' >/tmp/f.in && read res /tmp/f.in ... $ read res , at which time the t_sigio_rdwr process does get a SIGIO with si->si_fd == 1, but it is now too late - the reader has disconnected. Can anyone answer the question: For output (O_WRONLY|O_ASYNC) file descriptors, WHEN is the F_SETOWN signal or SIGIO meant to be sent ? Is it upon connection of a new reader FD to the read end of the the pipe, or when a reader FD is closed, or both ? IMHO, it must be possible to trigger the first case (sent on connection of new reader) but I can't see how to do it - the process only gets a SIGIO when a reader disconnects. -- You are receiving this mail because: You are watching the assignee of the bug. -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html