...d, the available bytes are returned. If no byte is available, read (2) will return -1 and errno will be set to EAGAIN . The O_NONBLOCK flag has no effect when opening /dev/urand…...d, the available bytes are returned. If no byte is available, read (2) will return -1 and errno will be set to EAGAIN . The O_NONBLOCK flag has no effect when opening /dev/urand…