DIALOUT(3) DIALOUT(3)
NAME
dialout - place call on ACU
SYNOPSIS
int dialout(telno, class)
char *telno, *class;
DESCRIPTION
Dialout places a data call via an automatic calling unit
directly attached to the calling computer. To use an ACU on
Datakit see the example in ipc(3).
Dialout searches for an ACU of the appropriate service class
and places a data call on the associated line, using the
given telephone number. If successful, it returns an open
file descriptor for the line. The file is in raw mode, and
has exclusive-use and hangup-on-close modes set. It returns
-1 if all ACUs of the given class are busy, -3 if carrier
could not be set, and -9 if the service class is unidentifi-
able.
The routine consults a data file that consists of lines con-
taining six blank- or tab-separated fields.
service class Each line with a service class matching the
one specified is tried in turn until an unoc-
cupied one is found. Service classes specify
a switching office and a baud rate.
Defined service classes at the `research'
site are 300 and 1200, for 300- and 1200-baud
calls on 665- phone lines, with synonyms D300
and D1200. Internal calls on these lines
require 5 digits. Service classes C300 and
C1200 use 582- phone lines. Internal calls
on these lines require 4 digits and reach
only other 582- lines.
file The file name of the associated special file
for the telephone line.
acu The file name of the associated ACU. If
specified as none, no ACU is used and the
telephone number is ignored. This is for
hardwired connections.
speed The bit rate of the interface, chosen from
the numbers given in ttyld(4).
prefix A string to be prefixed to the number. This
DIALOUT(3) DIALOUT(3)
is handy for shared ACUs in which the first
digit specifies a line. The prefix `-' is
taken to be an empty prefix.
postfix A string to be postfixed to the number to be
dialed. Some ACUs require an `end of number'
code; it should be specified here.
FILES
ttyld(4), cu(1), ipc(3)