This section contains notes and hints specific to installing PHP on Gentoo Linux.
While you can just download the PHP source and compile it yourself, using Gentoo's packaging system is the simplest and cleanest method of installing PHP. If you are not familiar with building software on Linux, this is the way to go.
If you have built your Gentoo system so far, you are probably used to Portage already. Installing Apache and PHP is no different than the other system tools.
The first decision you need to make is whether you want to install Apache 1.3.x or Apache 2.x. While both can be used with PHP, the steps given below will use Apache 1.3.x. Another thing to consider is whether your local Portage tree is up to date. If you have not updated it recently, you need to run emerge sync before anything else. This way, you will be using the most recent stable version of Apache and PHP.
Now that everything is in place, you can use the following example to install Apache and PHP:
例子 4-7. Gentoo Install Example with Apache 1.3
You can read more about emerge in the excellent Portage Manual provided on the Gentoo website.
If you need to use Apache 2, you can simply use emerge apache in the last example.
In the last section, PHP was emerged without any activated modules. As of this writing, the only module activated by default with Portage is XML which is needed by PEAR. This may not be what you want and you will soon discover that you need more activated modules, like MySQL, gettext, GD, etc.
When you compile PHP from source yourself, you need to activate modules via the configure command. With Gentoo, you can simply provide USE flags which will be passed to the configure script automatically. To see which USE flags to use with emerge, you can try:
例子 4-8. Getting the list of valid USE flags
As you can see from the last output, PHP considers a lot of USE flags. Look at them closely and choose what you need. If you choose a flag and you do not have the proper libraries, Portage will compile them for you. It is a good idea to use emerge -pv again to see what Portage will compile in accordance to your USE flags. As an example, if you do not have X installed and you choose to include X in the USE flags, Portage will compile X prior to PHP, which can take a couple of hours.
If you choose to compile PHP with MySQL, cURL and GD support, the command will look something like this:
As in the last example, do not forget to emerge php as well as mod_php. php is responsible for the command line version of PHP as mod_php is for the Apache module version of PHP.
If you see the PHP source instead of the result the script should produce, you have probably forgot to edit /etc/conf.d/apache. Apache needs to be started with the -D PHP4 flag. To see if the flag is present, you should be able to see it when using ps ax | grep apache while Apache is running.
Due to slotting problems, you might end up with more than one version of PHP installed on your system. If this is the case, you need to unmerge the old versions manually by using emerge unmerge mod_php-<old version>.
If you cannot emerge PHP because of Java, try putting -* in front of your USE flags like in the above examples.
If you are having problems configuring Apache and PHP, you can always search the Gentoo Forums. Try searching with the keywords "Apache PHP".