def set_block(fd):
    """Inverse of :func:`set_nonblock`, i.e. cause `fd` to block the thread
    when the underlying kernel buffer is exhausted."""
    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, flags & ~os.O_NONBLOCK)
def set_block ( fd ) : flags = fcntl . fcntl ( fd , fcntl . F_GETFL ) fcntl . fcntl ( fd , fcntl . F_SETFL , flags & ~ os . O_NONBLOCK )
Inverse of :func:`set_nonblock`, i.e. cause `fd` to block the thread
    when the underlying kernel buffer is exhausted.