original_string: public static function getUserEnvironmentVariable($var_name) {
      $result = getenv($var_name);
      if ($result === false) {
        $result = getenv(self::HTTP_X_APPENGINE . $var_name);
      }
      return $result;
    }
code: public static function getUserEnvironmentVariable($var_name) {
      $result = getenv($var_name);
      if ($result === false) {
        $result = getenv(self::HTTP_X_APPENGINE . $var_name);
      }
      return $result;
    }
code_tokens: public static function getUserEnvironmentVariable ( $ var_name ) { $ result = getenv ( $ var_name ) ; if ( $ result === false ) { $ result = getenv ( self :: HTTP_X_APPENGINE . $ var_name ) ; } return $ result ; }
docstring: Retrieve an environment variable specifically for the UserService.
  
  Under managed VMs, the UserService environment variables are sent as
  HTTP headers with the prefix 'HTTP_X_APPENGINE_'. This function first
  checks if the environment variable is set, and if not checks if it is
  set with the prefix string.
  
  @param string $var_name The variable name to check.
  
  @return The environment value, or false if not found.
docstring_tokens: Retrieve an environment variable specifically for the UserService .