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Passing Command Line Data to Check a Script

In order to test a script with different values, we need a way to make them accessible to the script. This can be done in two basic ways: from the Command Line or interactively. The script below utilizes arguments on the Command Line.

We will use the area-of-a-triangle problem for this demonstration.

A PHP Script to Handle Information Set on the Command Line

The following code should be saved in a file called triargsCL.php.

<?php
// triargsCL.php
// This script illustrates how to process information
// provided on the Command Line to a script for testing purposes

// Obtain the dimensions $b (base) and $h (height)
// of the triangle from the Command Line
$b = $argv[1];
$h = $argv[2];

echo "Calculating the Area of a Triangle\n";
// Print the base
echo "b is $b.\n";

// Print the height
echo "h is $h.\n";

// Calculate and print result
$A = $b * $h / 2;
echo "The area of a triangle with a base of $b and a height of $h is $A.\n";
?>

Notes

• Run this script by typing the following on the Command Line.
  

  php -f triargsCL.php 5 7

• Two variables are automatically created by PHP, $argc and $argv[]. The value of $argc is the count of the number of values being passed in $argv[]. $argv[] is an array containing the name of the script in zeroth element, $argv[0], and the values passed to that script in succeeding elements.
• To (partially) bulletproof the script, you can add the following line before assignment of the values occurs. This code fragment will cause the script to exit if an insufficient number of arguments have been included on the Command Line.

  if( $argc < 3 ) die("Too few arguments provided.\n");