A feature known as remote mode is available with the pseudo-TTY subsystem. This feature is used for applications that perform the canonical function normally done by ldterm(7M) and TTY driver. The remote mode allows applications on the master side to turn off the canonical processing. An TIOCREMOTE ioctl(2) with a nonzero parameter (ioctl(fd, TIOCREMOTE, 1)) is issued on the master side to enter the remote mode. When this occurs, an M_CTL message with the command MC_NO_CANON is sent to ldterm(7M) indicating that data should be passed when received on the read side and that no canonical processing is to take place. The remote mode may be disabled by ioctl(fd, TIOCREMOTE, 0).