Creating a PHP CLI Progress Bar

A terminal progress bar uses carriage returns to update a single status line.

What It Does

A terminal progress bar uses carriage returns to update a single status line. The following examples distinguish a normal use case, a boundary case and a practical application.

Requirements and Compatibility

PHP 8.x and a local test environment. Apply input validation, correct error handling and the requirements of any optional libraries.

The code focuses on the core concept. Production implementation may also need routes, validation, persistence, authorization or deployment tooling.

Example 1: Basic Behavior

Understand the primary operation and its inputs.

<?php
$argv = ['tool.php', '--task=export'];
$task = str_starts_with($argv[1], '--task=') ? substr($argv[1], 7) : '';
echo $argv[1]; // For actual parsing, call getopt() on the live CLI process

Example 2: Another Case

Check failure behavior or a different execution path.

<?php
$args = ['script.php', '--count', '5'];
$index = array_search('--count', $args, true);
$count = $index !== false ? filter_var($args[$index + 1] ?? null, FILTER_VALIDATE_INT) : false;
echo $count === false ? 'Invalid count' : $count;

Practical Example: Putting It to Use

A terminal progress bar needs bounded progress measurements and optional TTY detection.

<?php
$total = 10;
for ($done = 0; $done <= $total; $done += 5) { echo sprintf('[%-10s] %d%% ', str_repeat('#', $done), $done * 10); }

Important Behavior and Edge Cases

Only show interactive progress when stdout is a terminal; preserve useful logs in CI or cron.

Comparison with Related Functions or Approaches

Common Beginner Mistakes

Key Takeaways

• A terminal progress bar uses carriage returns to update a single status line.
• Only show interactive progress when stdout is a terminal; preserve useful logs in CI or cron.
• CLI tools should expose quiet and non-interactive modes.

Before adapting these examples, verify the return values, test the failure paths and confirm that your application meets its security and environment requirements.