Handling Program Options

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Program options can be handled with the getopt() function. It operates with a similar syntax to the POSIX getopt command, with additional support for GNU-style long options.


// a single colon indicates the option takes a value
// a double colon indicates the value may be omitted
$shortopts = "hf:v::d";
// GNU-style long options are not required
$longopts = ["help", "version"];
$opts = getopt($shortopts, $longopts);

// options without values are assigned a value of boolean false
// you must check their existence, not their truthiness
if (isset($opts["h"]) || isset($opts["help"])) {
    fprintf(STDERR, "Here is some help!\n");

// long options are called with two hyphens: "--version"
if (isset($opts["version"])) {
    fprintf(STDERR, "%s Version 223.45" . PHP_EOL, $argv[0]);

// options with values can be called like "-f foo", "-ffoo", or "-f=foo"
$file = "";
if (isset($opts["f"])) {
    $file = $opts["f"];
if (empty($file)) {
    fprintf(STDERR, "We wanted a file!" . PHP_EOL);
fprintf(STDOUT, "File is %s" . PHP_EOL, $file);

// options with optional values must be called like "-v5" or "-v=5"
$verbosity = 0;
if (isset($opts["v"])) {
    $verbosity = ($opts["v"] === false) ? 1 : (int)$opts["v"];
fprintf(STDOUT, "Verbosity is %d" . PHP_EOL, $verbosity);

// options called multiple times are passed as an array
$debug = 0;
if (isset($opts["d"])) {
    $debug = is_array($opts["d"]) ? count($opts["d"]) : 1;
fprintf(STDOUT, "Debug is %d" . PHP_EOL, $debug);

// there is no automated way for getopt to handle unexpected options

This script can be tested like so:

./test.php --help
./test.php --version
./test.php -f foo -ddd
./test.php -v -d -ffoo
./test.php -v5 -f=foo
./test.php -f foo -v 5 -d

Note the last method will not work because -v 5 is not valid.

Note: As of PHP 5.3.0, getopt is OS independent, working also on Windows.


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