Copyright (c) 1980 Regents of the University of California.
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@(#)rv.4 4.1 (Berkeley) 05/15/85

C 4 rv - Racal/Vadic ACU interface The racal/vadic ACU interface is provided by the files /dev/cua[01] which is a multiplexed file, and by the daemon dnd which monitors the file, simulating a standard DN dialer. To place an outgoing call one forks a sub-process trying to open /dev/cul? and then opens the corresponding file /dev/cua? file and writes a number on it. The daemon translates the call to proper format for the Racal/Vadic interface, and monitors the progress of the call recording accounting information for later use.

The codes for the phone numbers are the same as in the DN interface:

0-9 dial 0-9

.ns

: dial *

.ns

; dial #

.ns

- delay for second dial tone

.ns

< end-of-number

The entire telephone number must be presented in a single write system call.

It is require that an end-of-number code be given.

/dev/cua0 virtual dialer for 300 baud dialout

/dev/cua1 virtual dialer for 1200 baud dialout

/dev/cul0 the terminal which is connected to the 300 baud dialout

/dev/cul1 the terminal which is connected to the 1200 baud dialout

/usr/adm/dnacct Accounting records for sucessfully completed calls.

cu(1), uucp(1) Locking problems.

The multiplexor seems to have rare-case bugs which occasinally crash the system taking trap type 9's, usually in the sdata system routine.