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phpwindowsapc

What is apc_fetch(): apc_fcntl_rdlock`?

Fatal error: apc_fetch(): apc_fcntl_rdlock failed errno:6 in C:\Users\x\Documents\GitHub\xx\xxx\api\vendor\klein\klein\Klein\Klein.php on line 500

What is this error? And what might causing it?

APC is enabled and here is what I get from from phpinfo():

apc

APC Support enabled
Version 3.1.13
APC Debugging   Disabled
MMAP Support    Disabled
Locking type    File Locks
Serialization Support   php
Revision    $Revision: 327136 $
Build Date  Apr 23 2014 17:21:24
Solution

  • APC is the Alternative PHP Cache which is a great tool that speeds up PHP code on websites. But if you are doing local development—which you seem to be doing—you don’t need it. And it seems there are issues with APC on Windows machines. And the best, practical solution is to disable it completely as explained here.

    You need to find which php.ini is being loaded by your setup by looking at the output of phpinfo(). Then comment out the line that actually loads APC which looks like this:

    extension=apc.so

    And comment it out like this:

    ;extension=apc.so

    Or you can still load the apc.so yet disable it by setting this:

    apc.enabled = 1

    To this:

    apc.enabled = 0

    If you can’t find a line like that in php.ini then look for a file called apc.ini. On Ubuntu 12.04 it would be located in this path:

    /etc/php5/conf.d/apc.ini

    But if you are on a Windows machine that would obviously be somewhere else. The key is to look for conf.d which holds additional configuration files loaded by PHP such as apc.ini.

    Then restart your web server—Apache? IIS?—and you should be good.