Set blocking/non-blocking mode on a stream stream_select stream_set_timeout Stream Functions PHP Manual stream_set_blocking (PHP 4 >= 4.3.0, PHP 5)stream_set_blocking — Set blocking/non-blocking mode on a stream Description bool stream_set_blocking ( resource $stream , int $mode ) If mode is 0, the given stream will be switched to non-blocking mode, and if 1, it will be switched to blocking mode. This affects calls like fgets() and fread() that read from the stream. In non-blocking mode an fgets() call will always return right away while in blocking mode it will wait for data to become available on the stream. Returns TRUE on success or FALSE on failure. This function was previously called as set_socket_blocking() and later socket_set_blocking() but this usage is deprecated. Note: Prior to PHP 4.3, this function only worked on socket based streams. Since PHP 4.3, this function works for any stream that supports non-blocking mode (currently, regular files and socket streams). See also stream_select(). stream_select stream_set_timeout Stream Functions PHP Manual