autorun.php

#!/usr/bin/env php
<?php

if( ! function_exists( 'inotify_init' ) ) {
	die_with_error( 'This script needs the inotify module' );
}

// usage: $0 path [path ...] -- command

$args = $_SERVER['argv'];
array_shift( $args );

$toWatch = array();
while( false !== ( $arg = array_shift( $args ) ) ) {
	if( $arg === '--' ) {
		break;
	} else {
		if( ! file_exists( $arg ) ) {
			die_with_error( 'Cannot watch "%s", file or directory doest not exist' , $arg );
		}
		$toWatch[] = $arg;
	}
}

$command = implode( ' ' , array_map( 'escapeshellarg' , $args ) );

if( false === ( $fd = inotify_init() ) ) {
	die_with_error( 'inotify_init() failed' );
}

$countFile = $countDir = 0;

foreach( $toWatch as $watchThis ) {
	//echo 'watching: ' , $watchThis , PHP_EOL;
	inotify_add_watch( $fd , $watchThis , IN_MODIFY );

	if( is_dir( $watchThis ) ) {
		$countDir++;
		foreach( new RecursiveIteratorIterator( new RecursiveDirectoryIterator( $watchThis ) , RecursiveIteratorIterator::SELF_FIRST ) as $it ) {
			if( $it->isDir() ) {
				//echo 'watching: ' , $it->getPathname() , PHP_EOL;
				inotify_add_watch( $fd , $it->getPathname() , IN_MODIFY );
				$countDir++;
			}
		}
	} else {
		$countFile++;
	}
}

echo 'watching ' , ( $countDir ? $countDir . ' directories' : null ) , ( $countFile ? ( $countDir ? ' and ' : null ) . $countFile . ' files' : null ) , PHP_EOL;

echo 'waiting for changes...' , PHP_EOL;

while( false !== ( $events = inotify_read( $fd ) ) ) {
	foreach( $events as $event ) {
		echo '[' , translate_inotify_constant( $event['mask'] ) , '] ' , $event['name'] , '    : ' , json_encode( $event )  , PHP_EOL;

		echo 'executing: ' , $command , PHP_EOL;
		system( $command );
		/* eat up events that may have been triggered by the command */
		while( inotify_queue_len( $fd ) > 0 ) {
			$events = inotify_read( $fd );
		}
	}
	echo 'waiting for changes...' , PHP_EOL;
}

fclose( $fd );

function die_with_error( $msg )
{
	$args = func_get_args();
	array_shift( $args );

	vprintf( $msg . PHP_EOL , $args );
	exit -1;
}

function translate_inotify_constant( $value )
{
	static $const = null;

	if( null === $const ) {
		$const = get_defined_constants( true );
		$const = array_flip( $const['inotify'] );
	}

	return array_key_exists( $value , $const ) ? $const[ $value ] : $value;
}