stream_resolve_include_path()

(PHP 5 >= 5.3.2, PHP 7)

Resolve filename against the include path

说明

stream_resolve_include_path(string $filename): string

Resolve$filenameagainst the include path according to the same rules asfopen()/include.

参数

$filename

The filename to resolve.

返回值

Returns astringcontaining the resolved absolute filename,或者在失败时返回FALSE.

范例

Example #1stream_resolve_include_path()example

Basic usage example.

<?php
var_dump(stream_resolve_include_path("test.php"));
?>

以上例程的输出类似于：

string(22) "/var/www/html/test.php"

In case you're running a version of PHP that doesn't have this function...
if (!function_exists('stream_resolve_include_path')) {
  /**
   * Resolve filename against the include path.
   *
   * stream_resolve_include_path was introduced in PHP 5.3.2. This is kinda a PHP_Compat layer for those not using that version.
   *
   * @param Integer $length
   * @return String
   * @access public
   */
  function stream_resolve_include_path($filename)
  {
    $paths = PATH_SEPARATOR == ':' ?
      preg_split('#(?<!phar):#', get_include_path()) :
      explode(PATH_SEPARATOR, get_include_path());
    foreach ($paths as $prefix) {
      $ds = substr($prefix, -1) == DIRECTORY_SEPARATOR ? '' : DIRECTORY_SEPARATOR;
      $file = $prefix . $ds . $filename;
      if (file_exists($file)) {
        return $file;
      }
    }
    return false;
  }
}

stream_resolve_include_path() seems to cache it's output. After I renamed a file, I had to restart Apache for stream_resolve_include_path() to not return non-existing file name. This was on Windows.

It really behaves like `include` and will only resolve the filename against the include-path, if the path is relative. It makes not much sense to resolve already absolute pathnames anyway.

This seems to be a great alternative to file_exists.
if( file_exists(__DIR__.'/som-file.php') )
Goes way slower than:
if( stream_resolve_inlcude_path(__DIR__.'/som-file.php') !== false)