def setNonBlocking(fd):
 flags = fcntl.fcntl(fd, fcntl.F_GETFL)
 flags = (flags | os.O_NONBLOCK)
 fcntl.fcntl(fd, fcntl.F_SETFL, flags)

def setNonBlocking ( fd ) : flags = fcntl . fcntl ( fd , fcntl . F_GETFL ) flags = ( flags | os . O_NONBLOCK ) fcntl . fcntl ( fd , fcntl . F_SETFL , flags )
make a file descriptor non-blocking .