cserialio(7)                                                      cserialio(7)


NAME
     cserialio - character driver interface to serial communication ports

SYNOPSIS
     /dev/ttyc<portno>

DESCRIPTION
     On Origin, Octane and Challenge/Onyx systems, the special files
     /dev/ttyc* provide a character based interface (as opposed to a streams
     based interface) to the system serial ports. The hardware accessed by
     each special file is determined by the portno portion of the pathname
     (see serial(7) for further details). The character based interface is
     intended to provide a low cost option for applications wishing to do bulk
     data transfer via the serial ports with no character interpretation.
     There is no line discipline associated with this port type and no tty
     facilities are provided.

IOCTLS
     The ttyc ports support a limited subset of the ioctl set used to control
     ordinary tty ports. Specifically, ioctl functions which relate directly
     to the hardware are supported, whereas ioctl functions which relate to
     software functions of the tty interface such as the line discipline are
     not supported and may either fail or be silently ignored. In addition,
     streams ioctls will fail since this is not a streams device.

     For port hardware configuration, the ttyc interface supports the
     following ioctls as described in termio(7): TCGETA, TCSETA, TCSETAW,
     TCSETAF, TCGETS, TCSETS, TCSETSW, TCSETSF. Not all fields of the termio
     struct are relevant to the ttyc interface. The following fields are
     supported as described in termio(7): c_ospeed, CSIZE, CSTOPB, PARENB,
     PARODD, CNEW_RTSCTS. In addition the port will generate a SIGINT on
     reception of a break char if IGNBRK is false and BRKINT is true. Lastly,
     reads from ttyc ports will be non-blocking if ICANON is false, and VMIN
     and VTIME are 0. All other fields of the termio struct are silently
     ignored.

     The ttyc ports also honor the following ioctls as described in termio(7):
     TCSBRK, TCFLSH.

     Lastly, the following ioctls are supported as described in serial(7):
     SIOC_RS422, SIOC_EXTCLK, SIOC_ITIMER.

SEE ALSO
     serial(7), termio(7)


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