X-Recipient: archive-cygwin AT delorie DOT com X-SWARE-Spam-Status: No, hits=-1.1 required=5.0 tests=AWL,BAYES_50,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW X-Spam-Check-By: sourceware.org Message-ID: <4E2D474A.4000509@gmail.com> Date: Mon, 25 Jul 2011 12:36:58 +0200 From: Marco atzeri User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:5.0) Gecko/20110624 Thunderbird/5.0 MIME-Version: 1.0 To: cygwin Subject: Re: SIGHUP on pty closure References: <4E289D7B DOT 4050103 AT gmail DOT com> In-Reply-To: <4E289D7B.4050103@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com On 7/21/2011 11:43 PM, Marco atzeri wrote: > looking on the mc subshell issue, I found that mc > suppose that the subshell will receive a SIGHUP > when mc exit and close the master side of pty. > > Is such assumption wrong or it is a missing piece of > cygwin pty implementation ? > > > > ------------- extract from subshell.c -------------- > /* Attach all our standard file descriptors to the pty */ > > /* This is done just before the fork, because stderr must still */ > /* be connected to the real tty during the above error messages; */ > /* otherwise the user will never see them. */ > > dup2 (subshell_pty_slave, STDIN_FILENO); > dup2 (subshell_pty_slave, STDOUT_FILENO); > dup2 (subshell_pty_slave, STDERR_FILENO); > > close (subshell_pipe[READ]); > close (subshell_pty_slave); /* These may be FD_CLOEXEC, but just in > case... */ > /* Close master side of pty. This is important; apart from */ > /* freeing up the descriptor for use in the subshell, it also */ > /* means that when MC exits, the subshell will get a SIGHUP and */ > /* exit too, because there will be no more descriptors pointing */ > /* at the master side of the pty and so it will disappear. */ > close (subshell_pty); > > /* Execute the subshell at last */ > > switch (subshell_type) > { > case BASH: > execl (shell, "bash", "-rcfile", init_file, (char *) NULL); > break; > ---------------------------------------------------------- It seems that mc is correct in the expectation. http://pubs.opengroup.org/onlinepubs/9699919799/functions/close.html "If fildes refers to the master side of a pseudo-terminal, and this is the last close, a SIGHUP signal shall be sent to the controlling process, if any, for which the slave side of the pseudo-terminal is the controlling terminal. It is unspecified whether closing the master side of the pseudo-terminal flushes all queued input and output." I don't find such implementation on cygwin fhandler_pty_master::close () Am I looking in the wrong place ? Regards Marco -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple