V4/usr/man/man4/dn.4

Find at most related files.
including files from this version of Unix. 
.th DN IV 8/24/73
.sh NAME
dn \*- dn11 ACU interface
.sh DESCRIPTION
The
.it dn?
files
are write-only.
The permissible codes are:
.s3
.lp +8 4
0-9	dial 0-9
.lp +8 4
:	dial *
.lp +8 4
;	dial #
.lp +8 4
=	end-of-number
.s3
.i0
The entire telephone number must be
presented in a single
.it write
system call.
.s3
It is recommended that an end-of-number
code be given even though only one of the
ACU's (113C) actually requires it.
.dt
.sh FILES
/dev/dn0	connected to 801 with dp0
.br
/dev/dn1	connected to 113C with ttyc
.br
/dev/dn2	not currently connected
.sh "SEE ALSO"
dp(IV), dc(IV), write(II)
.sh BUGS
It needs a delay character to handle second dial tone.