Description:
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file_put_contents should support LOCK_NB just like it supports LOCK_EX.

luckily file_put_contents does not currently support any flags with the same value as LOCK_NB( LOCK_NB is 4 and FILE_USE_INCLUDE_PATH is 1 and FILE_APPEND is 8)

Test script:
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<?php
$file=__FILE__;
$fp=fopen($file,"rb");
flock($fp,LOCK_EX);
var_dump(file_put_contents($file,"test",LOCK_EX|LOCK_NB));

Expected result:
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bool(false) and perhaps some error about being unable to lock.

Actual result:
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script hangs indefinitely, because file_put_contents doesn't understand LOCK_NB