Chapter 6. Using the PHP scripting language

Hypertext Preprocessor (PHP) is a general-purpose scripting language mainly used for server-side scripting, which enables you to run the PHP code using a web server.

In RHEL 9, PHP is available in the following versions and formats:

  • PHP 8.0 as the php RPM package
  • PHP 8.1 as the php:8.1 module stream

6.1. Installing the PHP scripting language

This section describes how to install PHP.

Procedure

  • To install PHP 8.0, use: 

    # dnf install php

  • To install the php:8.1 module stream with the default profile, use: 

    # dnf module install php:8.1

    The default common profile installs also the php-fpm package, and preconfigures PHP for use with the Apache HTTP Server or nginx.

  • To install a specific profile of the php:8.1 module stream, use: 

    # dnf module install php:8.1/profile

    Available profiles are as follows:

  • common - The default profile for server-side scripting using a web server. It includes the most widely used extensions.
  • minimal - This profile installs only the command-line interface for scripting with PHP without using a web server.

  • devel - This profile includes packages from the common profile and additional packages for development purposes.

    For example, to install PHP 8.1 for use without a web server, use: 

    # dnf module install php:8.1/minimal

Additional resources

6.2. Using the PHP scripting language with a web server

6.2.1. Using PHP with the Apache HTTP Server

In Red Hat Enterprise Linux 9, the Apache HTTP Server enables you to run PHP as a FastCGI process server. FastCGI Process Manager (FPM) is an alternative PHP FastCGI daemon that allows a website to manage high loads. PHP uses FastCGI Process Manager by default in RHEL 9.

You can run the PHP code using the FastCGI process server.

Prerequisites

  • The PHP scripting language is installed on your system.

Procedure

  1. Install the httpd package: 

    # dnf install httpd

  2. Start the Apache HTTP Server: 

    # systemctl start httpd

    Or, if the Apache HTTP Server is already running on your system, restart the httpd service after installing PHP: 

    # systemctl restart httpd

  3. Start the php-fpm service: 

    # systemctl start php-fpm

  4. Optional: Enable both services to start at boot time: 

    # systemctl enable php-fpm httpd

  5. To obtain information about your PHP settings, create the index.php file with the following content in the /var/www/html/ directory: 

    # echo '<?php phpinfo(); ?>' > /var/www/html/index.php

  6. To run the index.php file, point the browser to: 

    http://<hostname>/

  7. Optional: Adjust configuration if you have specific requirements:

    • /etc/httpd/conf/httpd.conf - generic httpd configuration
    • /etc/httpd/conf.d/php.conf - PHP-specific configuration for httpd
    • /usr/lib/systemd/system/httpd.service.d/php-fpm.conf - by default, the php-fpm service is started with httpd
    • /etc/php-fpm.conf - FPM main configuration
    • /etc/php-fpm.d/www.conf - default www pool configuration

Example 6.1. Running a "Hello, World!" PHP script using the Apache HTTP Server

  1. Create a hello directory for your project in the /var/www/html/ directory: 

    # mkdir hello

  2. Create a hello.php file in the /var/www/html/hello/ directory with the following content: 

    # <!DOCTYPE html>
<html>
<head>
<title>Hello, World! Page</title>
</head>
<body>
<?php
    echo 'Hello, World!';
?>
</body>
</html>

  3. Start the Apache HTTP Server: 

    # systemctl start httpd

  4. To run the hello.php file, point the browser to: 

    http://<hostname>/hello/hello.php

    As a result, a web page with the “Hello, World!” text is displayed.

Additional resources

6.2.2. Using PHP with the nginx web server

You can run PHP code through the nginx web server.

Prerequisites

  • The PHP scripting language is installed on your system.

Procedure

  1. Install the nginx package: 

    # dnf install nginx

  2. Start the nginx server: 

    # systemctl start nginx

    Or, if the nginx server is already running on your system, restart the nginx service after installing PHP: 

    # systemctl restart nginx

  3. Start the php-fpm service: 

    # systemctl start php-fpm

  4. Optional: Enable both services to start at boot time: 

    # systemctl enable php-fpm nginx

  5. To obtain information about your PHP settings, create the index.php file with the following content in the /usr/share/nginx/html/ directory: 

    # echo '<?php phpinfo(); ?>' > /usr/share/nginx/html/index.php

  6. To run the index.php file, point the browser to: 

    http://<hostname>/

  7. Optional: Adjust configuration if you have specific requirements:

    • /etc/nginx/nginx.conf - nginx main configuration
    • /etc/nginx/conf.d/php-fpm.conf - FPM configuration for nginx
    • /etc/php-fpm.conf - FPM main configuration
    • /etc/php-fpm.d/www.conf - default www pool configuration

Example 6.2. Running a "Hello, World!" PHP script using the nginx server

  1. Create a hello directory for your project in the /usr/share/nginx/html/ directory: 

    # mkdir hello

  2. Create a hello.php file in the /usr/share/nginx/html/hello/ directory with the following content: 

    # <!DOCTYPE html>
<html>
<head>
<title>Hello, World! Page</title>
</head>
<body>
<?php
    echo 'Hello, World!';
?>
</body>
</html>

  3. Start the nginx server: 

    # systemctl start nginx

  4. To run the hello.php file, point the browser to: 

    http://<hostname>/hello/hello.php

    As a result, a web page with the “Hello, World!” text is displayed.

Additional resources

6.3. Running a PHP script using the command-line interface

A PHP script is usually run using a web server, but also can be run using the command-line interface.

Prerequisites

  • The PHP scripting language is installed on your system.

Procedure

  1. In a text editor, create a filename.php file

    Replace filename with the name of your file.

  2. Execute the created filename.php file from the command line: 

    # php filename.php

Example 6.3. Running a "Hello, World!" PHP script using the command-line interface

  1. Create a hello.php file with the following content using a text editor: 

    <?php
    echo 'Hello, World!';
?>

  2. Execute the hello.php file from the command line: 

    # php hello.php

    As a result, “Hello, World!” is printed.

6.4. Additional resources

  • httpd(8) — The manual page for the httpd service containing the complete list of its command-line options.
  • httpd.conf(5) — The manual page for httpd configuration, describing the structure and location of the httpd configuration files.
  • nginx(8) — The manual page for the nginx web server containing the complete list of its command-line options and list of signals.
  • php-fpm(8) — The manual page for PHP FPM describing the complete list of its command-line options and configuration files.