Description:
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The function php_uname() supports returning the OS Kernel string.  In the case of Linux, php_uname('s') returns 'Linux'.  However, there is a difference between returning the Kernel string, and returning an OS string.  

Under RedHat Linux : uname -o returns 'GNU/Linux'
Under Midori Linux : uname -o returns 'MIDORI/Linux'
Under QNX 6.3 : uname -o returns 'QNX'

Since the strings that uname -s, and uname -o differ, the php_uname function should also support the 'o' option.



Reproduce code:
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<?php

echo php_uname('s');
echo php_uname('o');

?>

Expected result:
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Under linux, I would expect to see

Linux
GNU/Linnux

Actual result:
--------------
Linux