COSC 2206: Internet Tools
Installing PHP with Apache

Getting and Installing PHP for Windows

We explain how to install PHP (PHP Hypertext Processor) for Windows and configure it as an Apache server module. It is assumed that you have already installed the Apache server.

There are two ways to install PHP: as an apache Module , or as a CGI program. The module version is better, faster, and more secure than the CGI version so we will only show how to install it.

You can install PHP from the CD-ROM or online. To install from the CD locate the file \software\php-4.3.8\php-4.3.8-Win32.zip. To install online go to the PHP web site www.php.net and find the file php-4.3.8-Win32.zip. Online there is also another installer version: DON'T GET IT. Unzip the file into your top level c:\ directory and you will have a directory called c:\php-4.3.8-Win32. Rename this directory to just c:\php. It should look like

The file install.txt gives details on how to configure PHP to work with various web servers. We won't need it for these notes since the following sections explain how to do this for the Apache web server.

The php.ini configuration file

There is an important file called php.ini-recommended in your installation directory c:\php . Copy this file to directory c:\windows and rename the copy to php.ini. This is the main configuration file for PHP. When we install PHP as an Apache module this file will be read every time the Apache server is started or restarted. It is important to note that each time you make changes to the php.ini file it is necessary to restart the Apache server before the changes take effect. We will now make some modifications to this file.

Search php.ini for the line 

doc_root =
and change it to 
doc_root = "c:\Apache\htdocs"
This specifies that our PHP root directory will be the same as the Apache root directory.

Installing PHP as an Apache module

First locate the file c:\php\php4ts.dll and copy it to c:\windows\system32.

Now we need to make some modifications to the Apache configuration file c:\apache\conf\httpd.conf. Before modifying httpd.conf make a copy of it called httpd.conf-original in case you make some mistakes.

Search httpd.conf until you find the section with all the LoadModule statements that are commented out (lines beginning with # are comment lines) and add the line 

LoadModule php4_module c:/php/sapi/php4apache.dll
at the end of this section. This line tells Apache to load the php module and where to find it in your file system.

Now locate the section of the file with all the AddModule statements. At the end of this section add the three lines 

AddModule mod_php4.c
AddType application/x-httpd-php .php
AddType application/x-httpd-php-source .phps

Testing PHP for Windows

Restart the Apache server or start it if it is not running so that the configuration changes will take effect: this causes httpd.conf and php.ini to be read. The command window should now show 
Apache/1.3.29 (Win32) PHP/4.3.8 running...
indicating that PHP has been successfully installed as a module. You can minimize this window.

To test your installation make a testphp directory under your htdocs directory for testing php scripts. In this directory create the following simple script called hello.php 

<html>
<head><title>Hello Script</title></head>
<body>
<?php echo "<h1>Hello PHP World!</h1>";?>
</body>
</html>
Now the full path to test.php should be c:\apache\htdocs\testphp\hello.php.

To execute the script enter the following url in a browser 

http://localhost/testphp/hello.php
and you should see a screen like

Displaying Error Messages

While you are learning and developing PHP scripts it is useful to have error messages displayed in the browser instead of just the Apache log files. This can be done by locating the lines 
; Print out errors (as a part of the output).  For production web sites,
; you're strongly encouraged to turn this feature off, and use error logging
; instead (see below).  Keeping display_errors enabled on a production web site
; may reveal security information to end users, such as file paths on your Web
; server, your database schema or other information.
display_errors = Off
in the php.ini file and changing display_errors = Off to display_errors = On

On a production server this should not be done for security reasons.

Installing PHP Extensions

There are many extensions that can be installed to provide more functionality. For example the gd library provides functions for dynamically creating jpg and png image files and the pdf library provides functions for dynamically creating pdf files. They are not installed by default.

To install these packages we need to define the extension directory to be c:\php\extensions because this is where the extension dll's are located. In this directory you will find files called php_gd2.dll and php_pdf.dll. To install these extensions you need to edit php.ini, find the lines (lines beginning with a semi-colon are comment lines in PHP) 

;extension=php_gd2.dll
and 
;extension=php_pdf.dll
and remove the semi-colons (uncomment the lines). Then search for the lines 
; Directory in which the loadable extensions (modules) reside.
extension_dir = "./"
and change the second line to 
extension_dir = "c:\php\extensions"

Session Management

We will be using PHP to do session management. For this it is necessary to create a directory that PHP can use to store the session files. This directory can be anywhere but a good place is in the Apache home directory, outside the document tree. Therefore create the directory c:\apache\sessions (PHP will not create it for you).

To tell PHP to put the session files there it is necessary to modify a line of the php.ini file. Locate the lines 

; Argument passed to save_handler.  In the case of files, this is the path
; where data files are stored. Note: Windows users have to change this 
; variable in order to use PHP's session functions.
;session.save_path = /tmp
and uncomment (remove initial semi-colon) the last line and change it to 
session.save_path = "c:\Apache\sessions"

Include Files

PHP supports include files and included files are best kept outside the document tree. To do this locate the lines 
; UNIX: "/path1:/path2"  
;include_path = ".:/php/includes"
;
; Windows: "\path1;\path2"
;include_path = ".;c:\php\includes"
and uncomment (remove initial semi-colon) the last line (Windows) and change it to 
include_path = ".;c:\php;c:\Apache\php-includes"
This means that include files will be searched for first in the current directory and then in c:\php and then in c:\Apache\php-includes.

It is necessary to restart Apache if it is running for these changes to php.ini to take effect.

PHP Documentation

The complete PHP documentation can be obtained in several formats from www.php.net. For Windows the best format is Windows help (chm) or extended help.

This is a searchable version of the 1800 page PHP documentation It comes in a file called php_manual_chm_12.zip and is available online at http://www.php.net/docs-echm.php or on the CD-ROM (\software\php-4.3.8\php_manual_chm_12.zip).

The best place to store the documentation is in the c:\php installation directory. Make a folder there called c:\php\docs and unzip the file into this directory.

Now you can execute the file c:\php\docs\php_manual_en.chm to see the documentation. For easier access make a shortcut to this file on the desktop. You can also use the nice phpZ skin by running php_manual_prefs.exe and choosing it from the skins box.

Some simple PHP script examples

The following scripts illustrate some of the features of PHP.

Displaying Apache/PHP configuration information

PHP comes with a built-in function called phpinfo() that will display comprehensive information about the Apache/PHP configuration and installed extensions. To use it create the following PHP script called info.php and put it in your testphp directory: 
<html>
<head><title>PHP Info</title></head>
<body>
<?php phpinfo(); ?>
</body>
</html>
Try it using the url http://localhost/testphp/info.php. You will see a comprehensive list of the Apache and PHP configuration information. Notice that our installed extensions gd and pdf are shown as enabled.

Processing a form

It is easy to both generate and process forms using the same PHP script. The following example script generates a form that has fields for a first name and a last name. The script then displays a greeting based on the names entered and provides a link to re-execute the script with a new form. If you don't want to type the script get it here. 
<?php
// ------------------------------------------------------------
// This script generates a form and prcessess the form.
// The value of the submit button is used to determine whether
// to display the form or process the form.
// If the submit button is undefined then the form is displayed
// else the form is processed
// ------------------------------------------------------------

if (isset($_REQUEST['button'])) // submit was clicked
{
   display_output_page();
}
else // display form for first time
{
   display_form_page();
}
?>

<?php
function display_form_page()
{
   $self = $_SERVER['PHP_SELF'];
?>
<html>
<head><title>PHP form example</title></head>
<body>
<h1>PHP form example</h1>
<form action="<?php echo $self ?>" method="POST">
First  name: <input type="text" name="firstname"><br>
Last name: <input type="text" name="lastname">
<p>
<input type="submit" name="button" value="Submit Name">
</form>
</body>
</html>
<?php
}
?>

<?php
function display_output_page()
{
   $self = $_SERVER['PHP_SELF'];
   $first_name = $_REQUEST['firstname'];
   $last_name = $_REQUEST['lastname'];
?>
   <html>
   <head><title>Form Results</title></head>
   <body>
   <h1>Form Results</h1>
   <?php echo "Hello $first_name $last_name<br/>\n"; ?>
   <p>
   <a href="<?php echo $self?>">Try another name</a>
   </body>
   </html>
<?php
}
?>
Put this script in your testphp directory and use the url http://localhost/testphp/process_form.php to execute it.