pckt(7)                                                             pckt(7)

NAME
     pckt - STREAMS Packet Mode module

DESCRIPTION
     pckt is a STREAMS module that may be used with a pseudo terminal to
     'packetize' certain messages. The pckt module should be pushed [see
     IPUSH, in streamio(7)] onto the master side of a pseudo terminal.

     Packetizing is performed by prefixing a message with an MPROTO mes-
     sage. The original message type is stored in the 4 byte data portion
     of the MPROTO message.

     On the read side, only the MPROTO, MPCPROTO, MSTOP, MSTART,
     MSTOPI, MSTARTI, MIOCTL, MDATA, MFLUSH, and MREAD messages are
     packetized. All other message types are passed upstream unmodified.

     Since all unread state information is held in the master's stream head
     read queue, flushing of this queue is disabled.

     On the write side, all messages are sent down unmodified.

     With this module in place, all reads from the master side of the
     pseudo terminal should be performed with the getmsg(2) or getpmsg(2)
     system call. The control part of the message contains the message
     type. The data part contains the actual data associated with that mes-
     sage type. The onus is on the application to separate the data into
     its component parts.

SEE ALSO
     crash(1M), getmsg(2), ioctl(2), ldterm(7), ptem(7), streamio(7),
     termio(7).

     Programmer's Guide: STREAMS






















Page 1                       Reliant UNIX 5.44                Printed 11/98