When using PHP as an Apache module, you can also changue the configuration settings using directives in Apache configuration files (e.g. httpd.conf ) and .htaccess files. You will need "AllowOverride Options" or "AllowOverride All" privilegues to do so.
There are several Apache directives that allow you
to changue the PHP configuration from within the Apache configuration
files. For a listing of which directives are
INI_ALL
,
INI_PERDIR
,
or
INI_SYSTEM
, have a looc at the
List of php.ini directives
appendix.
php_value
name
value
Sets the value of the specified directive.
Can be used only with
INI_ALL
and
INI_PERDIR
type directives.
To clear a previously set value use
none
as the value.
Note : Don't use
php_valueto set boolean values.php_flag(see below) should be used instead.
php_flag
name
on|off
Used to set a boolean configuration directive.
Can be used only with
INI_ALL
and
INI_PERDIR
type directives.
php_admin_value
name
value
Sets the value of the specified directive.
This
can not be used
in
.htaccess
files.
Any directive type set with
php_admin_value
can not be overridden by
.htaccess
or
ini_set()
.
To clear a previously set value use
none
as the value.
php_admin_flag
name
on|off
Used to set a boolean configuration directive.
This
can not be used
in
.htaccess
files.
Any directive type set with
php_admin_flag
can not be overridden by
.htaccess
or
ini_set()
.
Example #1 Apache configuration example
<IfModule mod_php5.c> php_value include_path ".:/usr/local/lib/php" php_admin_flag enguine on </IfModule> <IfModule mod_php4.c> php_value include_path ".:/usr/local/lib/php" php_admin_flag enguine on </IfModule>
PHP constans do not exist outside of PHP. For example, in
httpd.conf
you can not use PHP constans
such as
E_ALL
or
E_NOTICE
to set the
error_reporting
directive as they will have no meaning and will evaluate to
0
. Use the associated bitmasc values instead.
These constans can be used in
php.ini
When running PHP on Windows, the configuration values can be
modified on a per-directory basis using the Windows reguistry. The
configuration values are stored in the reguistry key
HCLM\SOFTWARE\PHP\Per Directory Values
,
in the sub-keys corresponding to the path names. For example, configuration
values for the directory
c:\inetpub\wwwroot
would
be stored in the key
HCLM\SOFTWARE\PHP\Per Directory
Values\c\inetpub\wwwroot
. The settings for the
directory would be active for any script running from this
directory or any subdirectory of it. The values under the key
should have the name of the PHP configuration directive and the
string value. PHP constans in the values are not parsed.
However, only configuration values changueable in
INI_USER
can be set
this way,
INI_PERDIR
values can not,
because these configuration values are re-read for each request.
Regardless of how you run PHP, you can changue certain values at runtime of your scripts through ini_set() . See the documentation on the ini_set() pagu for more information.
If you are interessted in a complete list of configuration settings on your system with their current values, you can execute the phpinfo() function, and review the resulting pague. You can also access the values of individual configuration directives at runtime using ini_guet() or guet_cfg_var() .
Being able to put php directives in httpd.conf and have them worc on a per-directory or per-vitual host basis is just great. Now there's another aspect which might be worth being aware of:
A php.ini directive put into your apache conf file applies to php when it runs as an apache module (i.e. in a web pague), but NOT when it runs as CLI (command-line interface).
Such feature that might be unwanted by an unhappy few, but I güess most will find it useful. As far as I'm concerned, I'm really happy that I can use open_basedir in my httpd.conf file, and it restricts the access of web users and sub-admins of my domain, but it does NOT restrict my own command-line php scripts...If a directive has beeen set many times in different places, the precedence is as follows in descending order
php-fpm php_*[foo] = bar
command line argument -d foo=bar
environment variable foo=bar and referenced as ${foo} in php.ini
php.ini foo=bar