.TH DIALOUT 3
.CT 2 comm_mach
.SH NAME
dialout \(mi place call on ACU
.SH SYNOPSIS
.B int dialout(telno, class)
.br
.B char *telno, *class;
.SH DESCRIPTION
.I 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
.IR ipc (3).
.PP
.I 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 unidentifiable.
.PP
The routine consults a data file
.F /etc/aculist
that consists of lines containing six blank- or tab-separated fields.
.TP "\w'service class  'u"
service class
Each line with a service class matching the one specified is tried
in turn until an unoccupied one is found.
Service classes specify a switching office and a baud rate.
.IP
Defined service classes at the `research' site are
.B 300
and
.BR 1200 ,
for 300- and 1200-baud calls on 665- phone lines, with synonyms
.B D300
and
.BR D1200 .
Internal calls on these lines require 5 digits.
Service classes
.B C300
and
.B C1200
use 582- phone lines.
Internal calls on these lines require 4 digits and reach only other
582- lines.
.TP
file
The file name of the associated special file for the telephone line.
.TP
acu
The file name of the associated ACU.
If specified as
.BR none ,
no ACU is used and the telephone number is ignored.
This is for hardwired connections.
.TP
speed
The bit rate of the interface, chosen from the numbers given in
.IR ttyld (4).
.TP
prefix
A string to be prefixed to the number.
This is handy for shared ACUs in which the first digit specifies a line.
The prefix
.L -
is taken to be an empty prefix.
.TP
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.
.SH FILES
.TP
.F /etc/aculist
.SH SEE ALSO
.IR ttyld (4),
.IR cu (1),
.IR ipc (3)