PHP Installation and Setup - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of PHP Version Check

What is the output of this PHP code snippet when run on a properly installed PHP 8.1 environment?

PHP

<?php
 echo PHP_VERSION;
?>

A php_version

B PHP_VERSION

C 8.1.x (where x is the patch version)

D SyntaxError

💡 Hint

PHP_VERSION is a predefined constant that holds the current PHP version as a string.

The PHP predefined constant PHP_VERSION outputs the current PHP version as a string, such as '8.1.0'. It does not output the literal string 'PHP_VERSION'.

❓ Predict Output

intermediate

Result of phpinfo() Function

What does the phpinfo() function output when called in a PHP script?

PHP

<?php
 phpinfo();
?>

A A detailed HTML page showing PHP configuration and environment

B A plain text list of PHP functions

C An error message about undefined function

D Nothing, it returns an empty string

💡 Hint

phpinfo() outputs configuration info about PHP in HTML format.

phpinfo() outputs a detailed HTML page that shows PHP version, configuration, loaded modules, environment variables, and more.

❓ Predict Output

advanced

Behavior of PHP Script Without Closing Tag

What happens if a PHP script file ends without the closing ?> tag?

PHP

<?php
 echo 'Hello, world!';

A The script runs normally and outputs 'Hello, world!'

B Syntax error due to missing closing tag

C The script outputs 'Hello, world!?>'

D The script outputs nothing

💡 Hint

PHP closing tag is optional at the end of a file.

In PHP, the closing ?> tag at the end of a file is optional and omitting it prevents accidental whitespace output. The script runs normally.

❓ Predict Output

advanced

Output of PHP Script with Short Open Tag Disabled

Given the following PHP code and assuming short_open_tag is disabled in php.ini, what will be the output?

PHP

<?php
 echo 'Test';
?>

A Syntax error due to short open tag

B The literal string '<? echo 'Test'; ?>' is output

C No output at all

D The string 'Test' is output

💡 Hint

Short open tags

If short_open_tag is disabled, PHP does not recognize '

🧠 Conceptual

expert

Understanding PHP Configuration File Location

Where does PHP look for its main configuration file (php.ini) by default when installed on a Linux system?

A /usr/local/lib/php.ini

B /var/www/html/php.ini

C /etc/php.ini

D /etc/php/8.1/cli/php.ini

💡 Hint

PHP version and SAPI (like CLI or Apache) affect the php.ini location.

On many Linux systems, PHP stores version-specific configuration files under /etc/php/{version}/{sapi}/php.ini, for example /etc/php/8.1/cli/php.ini for CLI PHP 8.1.