From:             [EMAIL PROTECTED]
Operating system: Linux
PHP version:      4.2.3
PHP Bug Type:     Sockets related
Bug description:  socket_accept() in blocking mode doesn't handle signal interrupts

The socket_accept() function doesn't appear to handle kernel level system
interrupts. This is a problem because PHP scripts written to use
pcntl_signal() won't be executed while socket_accept() is in blocking
mode. THAT is a problem because the script can't be killed with:

kill -s SIGUSR1 [pid]

and can't reap zombie processes when SIGCHLD is given (not that is much of
a problem on Linux, since you can use SIG_IGN).

A workaround I've made is to set a socket to non-blocking mode:

socket_set_nonblock($hSocket);

And then use a while loop like so:

while (($hClient = @socket_accept($hSocket)) === false) {
       
       // If this is a real error, we need to handle it. Unfortunately, in
this
       // event we just die() essentially.
       
       if (!is_resource($hSocket)) {

           error_log(socket_strerror(socket_last_error($hSocket)));
           exit;

       }
       
       // We need to sleep for one second so that CPU isn't absorbed with
this
       // process. This may seem clunky, but select() doesn't appear to
work
       // correctly with accept() in PHP in blocking mode (that is EINTR
does
       // not appear to work correctly), thus preventing signals from
being
       // received. This, in effect, makes the process unkillable. This is
the
       // workaround, for the moment.
       
       sleep(1);
       
}

While this works, it would be much better if it just returned when a
system interrupt is given like the C-equivalent does. This works because
the system can't receive messages from the kernel because it isn't
blocking.
-- 
Edit bug report at http://bugs.php.net/?id=20745&edit=1
-- 
Try a CVS snapshot:         http://bugs.php.net/fix.php?id=20745&r=trysnapshot
Fixed in CVS:               http://bugs.php.net/fix.php?id=20745&r=fixedcvs
Fixed in release:           http://bugs.php.net/fix.php?id=20745&r=alreadyfixed
Need backtrace:             http://bugs.php.net/fix.php?id=20745&r=needtrace
Try newer version:          http://bugs.php.net/fix.php?id=20745&r=oldversion
Not developer issue:        http://bugs.php.net/fix.php?id=20745&r=support
Expected behavior:          http://bugs.php.net/fix.php?id=20745&r=notwrong
Not enough info:            http://bugs.php.net/fix.php?id=20745&r=notenoughinfo
Submitted twice:            http://bugs.php.net/fix.php?id=20745&r=submittedtwice
register_globals:           http://bugs.php.net/fix.php?id=20745&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=20745&r=php3
Daylight Savings:           http://bugs.php.net/fix.php?id=20745&r=dst
IIS Stability:              http://bugs.php.net/fix.php?id=20745&r=isapi

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