Re: Question!

[Jorge Opaso Pazos <jopaso@trofeospazos.com>]

Luciano Miguel Ferreira Rocha wrote:
> On Wed, Sep 03, 2003 at 03:19:44PM -0300, Mariano Moreyra wrote:
> 
>>Hi!!
>>First...I'd like to know if there is any kind of digest on this list to see
>>old submited messages.
>>
>>Now...I have a little problem.
>>I have a process that is listening for incoming connections on a socket.
>>That process waits for a command and then
>>forks a child to run a bash script.
>>The problems is:
>>	- When the bash script runs the safe_mysql script to run MySql engine, it's
>>like the child process never ends.
>>	  And because of that, the parent can't close the connection with the
>>client socket.
>>	- But if the bash script doesn't run the safe_mysql script...the child
>>process dies successfully and everything end
>>	  Ok
>>
> 
> Hola,
> 
> Your problem should be the socket inherited by the child that will run
> the script. I suppose the child doesn't need it, does it?
> 
> So, close it and redirect /dev/null to stdin, stdout and stderr:
> if ((fork() == 0) { /* child */
> 	int fd;
> 	close(sock);
> 	fd = open("/dev/null", O_RDONLY);
> 	if (fd != 0) {
> 		dup2(fd, 0);
> 		close(fd);
> 	}
> 	fd = open("/dev/null", O_WRONLY);
> 	if (fd != 1) {
> 		dup2(fd, 1);
> 		close(fd);
> 	}
> 	fd = open("/dev/null", O_WRONLY);
> 	if (fd != 2) {
> 		dup2(fd, 2);
> 		close(fd);
> 	}
> 	execl("/usr/bin/safe_mysqld", "safe_mysqld", 0);
> 	_exit(1);
> }
> 
> Regards,
> Luciano Rocha
> -
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> 
Hi, Luciano:
popen redirect the stdout of the child to the stream created if the call 
is in the form:

	FILE f = popen("cmd", "r");

Bye.