Source

File: wp-includes/pomo/streams.php

class POMO_FileReader extends POMO_Reader {

		/**
		 * @param string $filename
		 */
		function __construct( $filename ) {
			parent::__construct();
			$this->_f = fopen( $filename, 'rb' );
		}

		/**
		 * PHP4 constructor.
		 *
		 * @deprecated 5.4.0 Use __construct() instead.
		 *
		 * @see POMO_FileReader::__construct()
		 */
		public function POMO_FileReader( $filename ) {
			_deprecated_constructor( self::class, '5.4.0', static::class );
			self::__construct( $filename );
		}

		/**
		 * @param int $bytes
		 * @return string|false Returns read string, otherwise false.
		 */
		function read( $bytes ) {
			return fread( $this->_f, $bytes );
		}

		/**
		 * @param int $pos
		 * @return boolean
		 */
		function seekto( $pos ) {
			if ( -1 == fseek( $this->_f, $pos, SEEK_SET ) ) {
				return false;
			}
			$this->_pos = $pos;
			return true;
		}

		/**
		 * @return bool
		 */
		function is_resource() {
			return is_resource( $this->_f );
		}

		/**
		 * @return bool
		 */
		function feof() {
			return feof( $this->_f );
		}

		/**
		 * @return bool
		 */
		function close() {
			return fclose( $this->_f );
		}

		/**
		 * @return string
		 */
		function read_all() {
			$all = '';
			while ( ! $this->feof() ) {
				$all .= $this->read( 4096 );
			}
			return $all;
		}
	}