Description:
------------
The flock() documentation:
http://php.net/manual/en/function.flock.php

Says:
It is also possible to add LOCK_NB as a bitmask to one of the above operations 
if you don't want flock() to block while locking. (not supported on Windows)

In my tests on Windows 7 x64, it does work. But what is true is that the failed 
flock() does not set &$wouldblock to 1.

Please see the test script below.
Both scripts must be run at the same time in PHP interactive mode or with a 
sleep() to avoid the lock being released automatically.

It would be interesting to test this behaviour on other versions of Windows 
(this might not be applicable to all of them), and update the documentation 
accordingly. Non-blocking locks are a really useful feature, and it would be 
nice to document this properly for Windows users.



Test script:
---------------

Script 1
--------

$f = fopen('file.txt', 'w');
var_export(flock($f, LOCK_EX | LOCK_NB, $wouldblock)); // true
var_export($wouldblock); // 0

Script 2
--------

$f = fopen('file.txt', 'w');
var_export(flock($f, LOCK_EX | LOCK_NB, $wouldblock)); // false
var_export($wouldblock); // 0 (1 on Linux)