This look familiar?

PHP Warning:  PHP Startup: memcached: Unable to initialize module
Module compiled with module API=20090626
PHP    compiled with module API=20100525
These options need to match

I don’t know about you, but i like to be up to date! My PHP is on 5.5, and I had to install some modules. But sometimes, old versions can rear their ugly head, and cause all manner of grief. Package managers do a good job to take care of all this for you, but sometimes they just don’t work. Leaving you to compile yourself! So lets do it! I’m going to install memcached, and then the imagick libraries (now i know what i’m doing!)

I’m doing this on a CentOS 6 server, but as we are doing the old skool way of compiling etc, this should work on any other flavour of Linux, or indeed Mac OS X.

First step is to download your .tar.gz  then unzip it with tar -zxvf file.tar.gz and change into the folder.
Bring up a web page displaying your servers php.ini. You are looking for the version of PHP API, and the extension_dir.
In your terminal, cd into the module source code folder, and type phpize.

If when you check the API versions , they are different from your php.ini, then an old version of php is being used in the terminal, and your module will not work! In this case, you need to get it to use the correct phpize.

type 'which phpize' to find out where the offending file is. (mine was /usr/bin/phpize)

My PHP appeared to be in /usr/local, so I tried running /usr/local/phpize. The API’s matched. So then I did the following:

mv /usr/bin/phpize /usr/bin/phpize-old
 ln -s /usr/local/bin/phpize /usr/bin/phpize

Half way there! We need to do the same for php-config

mv /usr/bin/php-config /usr/bin/php-config-old
 ln -s /usr/local/bin/php-config /usr/bin/php-config

Now you have done that, installation should be trivial, and work as per loads of tutorial/instrruction pages on the web.

 make install

Finally edit your php.ini and add ‘extension =’ (or whatever module you compiled), and restart your apache server!

EDIT : you may need to run ‘phpize –clean’ if it is still compiling with the older stuff from within the modules source folder