From: tstarling at wikimedia dot org
Operating system: Windows
PHP version: 5.2.5
PHP Bug Type: Feature/Change Request
Bug description: Deadlock-free exec function
Description:
------------
I would like to request the addition of a deadlock-free shell execution
function to PHP on Windows. PHP already has one of these on the Linux
platform, and I think it would be a useful addition to the Windows platform
as well.
PHP deadlocks whenever an exec function is called, if another thread is
waiting for a file lock that the executing thread holds. This is the
expected behaviour and is not a bug, see bug 42064. But some applications
may benefit from the ability to call a shell execution function during a
file-lock-protected critical section without risking a permanent deadlock
of the participating threads. That is why I am making this feature request.
Reproduce code:
---------------
<?php
if ( isset( $_REQUEST['f'] ) ) {
$f = fopen( 'blah', 'w' );
flock( $f, LOCK_EX );
sleep( 1 );
passthru( "echo Hello" );
} else {
$self = $_SERVER['SCRIPT_NAME'];
echo <<<EOT
<html>
<frameset rows="50%, 50%">
<frame src="$self?f=1"/>
<frame src="$self?f=2"/>
</frameset>
</html>
EOT;
}
?>
Expected result:
----------------
The two frames should both display "Hello", after a delay of 2 seconds.
Actual result:
--------------
The frames take forever to load. Requires a force quit of Apache.
--
Edit bug report at http://bugs.php.net/?id=43588&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=43588&r=trysnapshot44
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=43588&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=43588&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=43588&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=43588&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=43588&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=43588&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=43588&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=43588&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=43588&r=support
Expected behavior: http://bugs.php.net/fix.php?id=43588&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=43588&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=43588&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=43588&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=43588&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=43588&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=43588&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=43588&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=43588&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=43588&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=43588&r=mysqlcfg