List all files in a directory tree.

Here is recursive way:

<?php
	function rec_listFiles( $from = '.')
	{
		if(! is_dir($from))
		return false;

		$files = array();
		if( $dh = opendir($from))
		{
			while( false !== ($file = readdir($dh)))
			{
				// Skip '.' and '..'
				if( $file == '.' || $file == '..')
				continue;
				$path = $from . '/' . $file;
				if( is_dir($path) )
				$files += rec_listFiles($path);
				else
				$files[] = $path;
			}
			closedir($dh);
		}
		return $files;
	}
?>

<?php
	function listFiles( $from = '.')
	{
		if(! is_dir($from))
		return false;
		$files = array();
		$dirs = array( $from);
		while( NULL !== ($dir = array_pop( $dirs)))
		{
			if( $dh = opendir($dir))
			{
				while( false !== ($file = readdir($dh)))
				{
					if( $file == '.' || $file == '..')
					continue;
					$path = $dir . '/' . $file;
					if( is_dir($path))
					$dirs[] = $path;
					else
					$files[] = $path;
				}
				closedir($dh);
			}
		}

		return $files;
	}
?>

<?php
	function rec_listFiles( $fileName, $from = '.', &$pathOut)
	{
		if ($pathOut != '')
			return true;
		else
		{

			if(! is_dir($from))
				return false;

			if( $dh = opendir($from))
			{
				while( false !== ($file = readdir($dh)))
				{
					// Skip '.' and '..'
					if( $file == '.' || $file == '..')
						continue;
					$path = $from . '/' . $file;
					if( is_dir($path) )
					{
						//echo $path.'<p/>';
						rec_listFiles($fileName, $path, $pathOut);
					}
					else
					{
						if ($fileName == $file)
						{
							$pathOut = $path;
						}
					}
				}
			closedir($dh);
			}
			if ($pathOut == '')
				return false;
			else
				return true;
		}
	}

	$pom = '';
	if (rec_listFiles('mod_newsflash.php', '.', $pom))
	echo $pom;
	else
	echo 'Could not find file.';
?>