Regardless of the installation variation you choose, you’ll need to begin by
decompressing the distributions. This is accomplished in two easy steps:
1. Unzip the packages. Once done, you’ll see that the files will be left with
*.tar extensions:
gunzip apache_1.3.9.tar.gz
gunzip php-4.0.0.tar.gz
2. Untar the packages. This will unarchive the distributions:
tar -zxvf apache_1.3.x.tar
tar -zxvf php-4.0.x.tar
The installation procedure will pick up from this point.
Apache Module
Installing PHP as an Apache module is rather simple. I’ll take you through each
step here:
1. Change location to the Apache directory:
cd apache_1.3.x
2. Configure Apache. You can use any path you like. Keep in mind that a
slash does not follow the pathname:
./configure —prefix=[path]
3. Change the location to the PHP directory and configure, build, and install
the distribution. The option with-config-file-path specifies the directory
that will contain PHP’s configuration file. Generally, this path is set to be
/usr/local/lib, but you can set it to be anything you wish:
./configure –with-apache=../apache_1.3.x —with-config-file-path=[config-path]
make
make install
An Introduction to PHP
13
4. Change back to the Apache directory. Now you will reconfigure, build,
and install Apache. The other-configuration-options option refers to any
special configuration options that you would like to pass along to the
Apache Web server. This is beyond the scope of this book. I suggest
checking out the Apache documentation for a complete explanation of
these options:
./configure –activate-module=src/modules/php4/libphp4.a
—other-configuration-options
make
make install
5. The final step involves modifying Apache’s httpd.conf file. Some of these
modifications relate specifically to Apache, while others are necessary to
ensure that PHP scripts can be recognized and sent to the Web server.
First, locate the line that reads:
ServerName new.host.name
Change this line to read:
ServerName localhost
Next, locate the following two lines:
#AddType application/x-httpd-php .php .php4
#AddType application/x-httpd-php-source .phps
These lines need to be uncommented in order for PHP-enabled files to work
correctly on the server. To uncomment these lines, simply remove the pound
symbol (#) from the beginning of each line. Save the file and move up one directory.
Start the Apache server using the following command:
./bin/apachectl start
Voilà! PHP and Apache are now ready for use. For testing purposes, insert the
following code into a file and save the file as phpinfo.php to the Apache’s document
root directory. This is the directory called htdocs, located in the Apache
installation directory.
php_info();
?>
Chapter 1
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Open this file up in a browser on the server. You should see a lengthy list of
information regarding PHP’s configuration. Congratulations, you’ve successfully
installed PHP as an Apache Module.
Dynamic Apache Module
The Dynamic Module is useful because it allows you to upgrade your PHP distribution
without having to recompile the Web server as well. Apache considers it
just another one of its many modules, like ModuleRewrite or ModuleSpelling.
This idea becomes particularly useful when you want to add some kind of support
to PHP later, encryption, for example. All you have to do is reconfigure/compile
PHP in accordance with the encryption support, and you can immediately
begin using it in your Web applications. Here is the installation process:
1. Change location to the Apache directory:
cd apache_1.3.x
2. Configure Apache. You can use any path you like. Keep in mind that a
slash does not follow the pathname. The –other-configuration-options
option refers to any special configuration options that you would like to
pass along to the Apache Web server. This is beyond the scope of this
book. I suggest checking out the Apache documentation for a complete
explanation of these options:
./configure —prefix=[path] —enable-module=so —other-configuration-options
3. Build the Apache server. After typing make, you will see a bunch of messages
scroll by. This is normal.
make
4. Install the Apache server. After you type make install, another bunch of
messages will scroll by. Again, this is normal. Once this has finished,
you’ll see a message stating that you have successfully installed the
server.
make install
5. Assuming no errors occurred, you’re ready to modify Apache’s
“httpd.con” file. This file is located in the conf directory in the path that
An Introduction to PHP
15
you designated in step 4. Open this file in your favorite text editor. Locate
the following line:
ServerName new.host.name
Modify this line to read:
ServerName localhost
6. Change location to the directory in which you downloaded PHP. Then,
configure, make, and install PHP. You will need to specify the path directory
pointing to the apxs file. This file can be found in the bin directory of
the path you designated in step 4.
./configure —with-apxs=[path/to/apxs]
make
make install
7. Reopen Apache’s httpd.conf file for another modification. In order for
incoming requests for PHP-enabled files to be properly parsed, the file
extension must coincide with the one as specified in the Apache server’s
configuration file, httpd.conf. This file contains a number of options,
which can be modified at the administrator’s discretion; a few of these
options relate directly to PHP. Open the httpd.conf file in your favorite
text editor. Towards the end of the file are two lines similar to the following:
#AddType application/x-httpd-php .php .php4
#AddType application/x-httpd-php-source .phps
8. You must uncomment these in order for PHP-enabled files to work correctly
on the server. To uncomment these lines, simply remove the pound
symbol (#) from the beginning of each line.
9. Save the file and move up one directory (to cd). Start the Apache server
using the following command:
./bin/apachectl start
Voilà! PHP and Apache are now ready for use.
Chapter 1
16
For testing purposes, insert the following code into a file and save the file as
phpinfo.php to the Apache’s document root directory. This is the directory called
htdocs, located in the Apache installation directory.
php_info();
?>
Open this file up in a browser on the server. You should see a lengthy list of
information regarding PHP’s configuration. Congratulations, you’ve successfully
installed the Dynamic Apache Module.
Installation on Windows 95/98/NT
If you have installed an application on the Windows operating system, you have
probably found it to be very easy. Click a few buttons, agree to a few statements,
and the application is installed. And so is the case with the installation of Apache
and PHP on a Windows machine.
1. Double-click the Apache executable to begin the installation. You will be
greeted with an installation wizard. Read attentively and accept the
licensing agreement.
2. The wizard will suggest a default installation directory
(C:\Program Files\Apache Group\Apache). This is fine, but you may want
to shorten it to just C:\Apache\. However, it’s up to you.
3. You will then be prompted for what name you would like to have appear
in the Start menu. Enter whatever you want, or accept the default.
4. Next you will be prompted for the installation type. Just pick Typical.
After you make your choice, the installation process is carried out.
5. Now it is time to modify the “httpd.conf” file, located in the conf directory,
which is located in whatever directory you chose to install the
Apache server in step 2. Open this file using your favorite text editor.
You’ll probably want to make at least three basic modifications:
An Introduction to PHP
17
Replace yourname@yoursite.com with the correct information.
ServerAdmin yourname@yoursite.com
Uncomment this line and place the correct server name. Just use localhost
if you do not have an actual server name:
ServerName localhost
6. Attempt to start Apache to ensure that everything is working. At this
point you need to make the differentiation as to the type of Windows OS
you are using:
If you’re using Windows NT, choose “Install Apache as Service (NT Only)”
from the Start menu. Then go to the Control Panel, open up the Services
window, choose Apache, and click the “Start” button. Apache will start,
and it will start automatically at every subsequent boot of the machine.
If you’re not using Windows NT, choose “Start Apache” from the Start
menu. A small window will open. This window must be kept open in
order for the server to run.
7. Finally, go to a browser installed on the server and enter
http://localhost/. You should see a default page stating that the installation
has been carried out correctly.
8. Now it’s time to install PHP. Change the directory to wherever you downloaded
the PHP package. Extract it to the directory of your choice using
an unzipping application.
9. Go to that directory and look for a file entitled “php.ini-dist”. Rename this
file to php.ini and place it in the C:\Windows\ directory.
10. Go back to the PHP directory. Look for two more files, php4ts.dll and
Mscvrt.dll. Place these files in the C:\Windows\System\ directory. You
probably already have the Mscvrt.dll file, and you will be prompted to
overwrite it. Don’t overwrite the file or copy it.
11. Return to the Apache http.conf file, again opening it up in a text editor.
There are a few more modifications that you need to make:
[(H2L)]
18
Look for this line:
ScriptAlias /cgi-bin/ "C:/Apache/cgi-bin/"
Directly below this line, add the following:
ScriptAlias /php4/ "C:/php4/"
Then search for “AddType”. You will see the following two commented lines:
#AddType application/x-httpd-php3 .phtml
#AddType application/x-httpd-php3-source .phps
Directly below these lines, add the following:
AddType application/x-httpd-php .phtml .php
AddType application/x-httpd-php-source .phps
Keep scrolling down. You will find the following commented lines:
#
# Action lets you define media types that will execute a script whenever
# a matching file is called. This eliminates the need for repeated URL
# pathnames for oft-used CGI file processors.
# Format: Action media/type /cgi-script/location
# Format: Action handler-name /cgi-script/location
#
Below this, add the following:
Action application/x-httpd-php /php4/php.exe
12. Voilà! PHP and Apache are now ready for use.
For testing purposes, insert the following code into a file and save the file as
“phpinfo.php” to the Apache’s document root directory. This is the directory
called htdocs located in whatever directory you specified in step 4.
php_info();
?>
[(H1L)]
19
Open this file in a browser on the server. You should see a lengthy list of information
regarding PHP’s configuration.
PHP Configuration
Although PHP will correctly run given its default configuration setting, you can
make quite a few modifications to fine-tune the installation to your needs. The
php.ini file, copied by default into the /usr/local/lib/ directory during the installation
process, contains all of these configuration settings.
Regardless of the platform and Web server used in conjunction with PHP, the
php.ini file will contain the same default set of parameters, from which several
important characteristics of the PHP installation can be administered. This file
contains all of the characteristics relevant to how your installation will act when
PHP scripts are executed. The PHP engine reads the php.ini file when PHP
starts up.
General Configuration Directives
Reiterating all of the configuration directives is beyond the scope of this book, but
there are several directives worth mentioning, as most the developers may find
them particularly useful. I’ll mention other directives as appropriate in subsequent
chapters.
Chapter 1
20
CAUTION Although successfully completing the steps outlined above does
make it possible for the Web server/PHP configuration to be used for testing
purposes, it does not imply that your Web server is accessible via the World
Wide Web. Check out the official Apache site ( http://www.apache.org) for
information regarding this matter. Furthermore, although the preceding
steps suffice to get the PHP package up and running, you will probably be
interested in modifying PHP’s configuration to best suit your needs. See
“PHP Configuration,” later in this chapter, for details.
NOTE The configuration file is entitled php3.ini in the 3.0 version but has
been changed to php.ini in the 4.0 version.
short_open_tag [on | off]
The short_open_tag [on | off] configuration directive determines the use of the
short PHP escape tags , in addition to the default tags.
asp_tags [on | off]
The asp_tags [on | off] configuration directive determines the use of ASP style tags
in addition to the default tags. ASP style tags are those that enclose PHP code as
follows:
<%
print "This is PHP code.";
%>
precision [integer]
The precision [integer] configuration directive sets the number of significant digits
displayed in floating point numbers.
safe_mode [on | off]
Turning on safe mode is a particularly good idea if you have several users on your
system. Essentially, turning on safe mode eliminates the possibility that a user
can use a PHP script to gain access to another file on the system, for example, the
passwd file on a Linux machine. Safe_mode works solely on the CGI version of
PHP. Check out Chapter 16 for more details regarding this matter.
max_execution_time [integer]
The max_execution_time [integer] configuration directive determines the maximum
number of seconds that a given PHP script may execute. This prevents runaway
scripts from eating up valuable system resources.
error_reporting [1–8]
The error_reporting [1-8] configuration directive gauges to what degree errors will
be reported, if any. The higher the bit value, the more sensitive PHP will be to
reporting errors:
An Introduction to PHP
21
BIT VALUE REPORTING SENSITIVITY
1 normal errors
2 normal warnings
4 parser errors
8 notices
display_errors [on | off]
The display_errors [on | off ] configuration directive display the errors in the
browser.
log_errors
The log_errors configuration directive determines whether or not errors are
logged to a file. If log_errors is turned on, the directive error_log designates which
file the errors are logged to.
error_log [filename]
If log_errors is turned on, error_log designates the filename to which all errors
should be logged.
magic_quotes_gpc
When magic_quotes_gpc is activated, all special characters contained in user or
database data will automatically be escaped with the necessary backslash. By the
way, “gpc” stands for “get/post/cookie”.
Personally, I find it more efficient to keep magic_quotes_gpc turned off and to
escape the special characters explicitly. Regardless of the way you ultimately
decide to do it, there can be no compromise or your data may be corrupted. If
magic_quotes_gpc is “on”, then never physically escape special characters with a
backslash; otherwise, make it a habit to always do so.
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