mux(1M) mux(1M)
NAME
mux - control connection to a cluster terminal
SYNOPSIS
/sbin/mux realterminal pseudoterminal [options]
/sbin/mux realterminal gettytype
DESCRIPTION
The mux command handles the protocol used to communicate with a clus-
ter terminal which is connected to a Reliant UNIX host. It allows the
multiplexing of a terminal and a second device on the same line.
There are two distinct modes of operation. The first is the preferred
method as it gives greater control to the operation of mux. In the
first mode, the mux process has at least two parameters. The first is
the line to which the cluster terminal is connected, whereas the
second is the name of the pseudo device through which the user process
is to be connected. Any additional options specified, control the
various parameters used by mux (see the OPTIONS section for more
details). With this mode, mux is usually started at boot time from SAC
(Service Access Controller).
The second mode of operation is only available if the mux process has
been compiled to support it. If not, then an error message is gen-
erated and mux be terminated.
In this mode, the first parameter is the name of the line to which the
cluster terminal is connected, whereas the second parameter is a sin-
gle letter defining one of a set of options. These options define the
operation of the mux process. In this mode, mux also starts a getty
process on the pseudo terminal that is created.
In this mode, mux would normally be started from /etc/init. This mode
is for backwards compatibility to an older version of mux.
The second parameter can have one of the following values. If the
second parameter does not come from this list, the other parameters
are used, and the second parameter is passed directly to the getty
when it is started.
Parameter Speed Protocol Windowsize Nchans gettyparm
A 38400 No 2 1 N
E 38400 Yes 2 2 N
C 38400 No 2 1 N
D 38400 Yes 2 2 N
a 1200 No 2 1 h1200
b 1200 Yes 2 2 h1200
c 2400 No 2 1 h2400
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mux(1M) mux(1M)
d 2400 Yes 2 2 h2400
e 9600 No 2 1 h
g 9600 Yes 2 2 h
z 38400 No 8 1 S
Z 38400 Yes 8 2 S
other 38400 Yes 8 2 other
No other options are available in this mode. If the number of channels
is greater than one, mux opens /etc/cluster and looks for an entry for
the given real device. If one is found, the second channel is config-
ured using the information provided in /etc/cluster; otherwise, no
second channel is configured.
OPTIONS
In the first mode of operation, the following options can be speci-
fied:
-C device This informs mux that the second device is a chip card ter-
minal which is to have the name given by the device parame-
ter. A parameter must be supplied.
-D device This informs mux that the second device is a printer which
is to have the name given by the device parameter. A parame-
ter must be supplied.
-B device This informs mux that the second device is another terminal
which is to have the name given by the device parameter. A
parameter must be supplied.
-S device This informs mux that the second device is a special device
with unknown characteristics. The name of the device is
given by the device parameter. A parameter must be supplied.
-G speed This option sets the speed of the real terminal line to be
speed. Values currently supported are:
1200, 2400, 9600, 38400
-L This option forces the mux process to use large window sizes
and a large buffer space for increased performance. This
option does not work on some cluster terminals.
-N By default, the mux process uses a multiplexing protocol to
communicate with the cluster terminal. This flag forces this
protocol off so that the terminal works in basic mode. In
this mode, no additional devices may be connected.
The specification of a second device forces the use of a
multiplexing protocol.
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mux(1M) mux(1M)
-T params This option is used for controlling the optional trace pack-
age. A special version of the mux process, which includes a
tracing facility, must be available for this option to take
effect. It is for the use of mux maintainers only.
FILES
/etc/cluster
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