Migrating from PHP 3 to PHP 4
PHP Manual

Migrating Configuration Files

The global configuration file, php3.ini, has changed its name to php.ini.

For the Apache configuration file, there are slightly more changes. The MIME types recognized by the PHP module have changed.

application/x-httpd-php3 --> application/x-httpd-php application/x-httpd-php3-source --> application/x-httpd-php-source

You can make your configuration files work with both versions of PHP (depending on which one is currently compiled into the server), using the following syntax:

AddType application/x-httpd-php3 .php3 AddType application/x-httpd-php3-source .php3s AddType application/x-httpd-php .php AddType application/x-httpd-php-source .phps

In addition, the PHP directive names for Apache have changed.

Starting with PHP 4.0, there are only four Apache directives that relate to PHP:

php_value [PHP directive name] [value] php_flag [PHP directive name] [On|Off] php_admin_value [PHP directive name] [value] php_admin_flag [PHP directive name] [On|Off]

There are two differences between the Admin values and the non admin values:

To make the transition process easier, PHP 4 is bundled with scripts that automatically convert your Apache configuration and .htaccess files to work with both PHP 3 and PHP 4. These scripts do NOT convert the mime type lines! You have to convert these yourself.

To convert your Apache configuration files, run the apconf-conv.sh script (available in the scripts/apache/ directory). For example:

~/php4/scripts/apache:# ./apconf-conv.sh /usr/local/apache/conf/httpd.conf

Your original configuration file will be saved in httpd.conf.orig.

To convert your .htaccess files, run the aphtaccess-conv.sh script (available in the scripts/apache/ directory as well):

~/php4/scripts/apache:# find / -name .htaccess -exec ./aphtaccess-conv.sh {} \;

Likewise, your old .htaccess files will be saved with an .orig suffix.

The conversion scripts require 'awk' to be installed.

Migrating from PHP 3 to PHP 4
PHP Manual