Description:
------------
when I have 2 files t and t2 and I try to diff them with

diff <(cat t) <(cat t2) LINUX-shell produces 2 meta-files (/dev/fd/[00-99]) to pipe into the diff command. Thats usual, thats basic.
If I try to use the same command in passthru("diff <(cat t) <(cat t2)"); I run into errors:
sh: -c: line 1: syntax error near unexpected token '('
sh: -c: line 1: 'diff <(cat t) <(cat t2)'
The files are in the PATH and I can see output of t when I do: passthru("cat t"); what means that cat is available too.


Reproduce code:
---------------
file X.php4:
-----snip--------
<?php passthru("diff <(cat t) <(cat t2)"); ?>
-------snap------

shell:> php X.php4

Expected result:
----------------
1,3c1,4
< MIKE
< bravo
< charly
---
> VANDA
> PHP
> Utah
> russia

Actual result:
--------------
sh: -c: line 1: syntax error near unexpected token '('
sh: -c: line 1: 'diff <(cat t) <(cat t2)'