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cmx - Generic communication exerciser
/usr/field/cmx [-b [minbaud]-[maxbaud]] [-h] [-ofile] [-tn] -l line-n...
Use this option to specify the minimum, maximum, or range of baud rates
-h Prints help messages about the cmx command.
Test all the listed tty lines, where n equals the lines to test
according to the special device file entries in the /dev directory,
such as 00, 12, or 42-53
Saves output diagnostics in file.
-tn Specifies the run time in minutes (n). The default is to run until a
[CTRL-C] or a kill -15 pid is sent to the process.
The cmx exerciser writes, reads, and validates random data and packet
lengths on a specified communications line. The line being tested must have
a loopback connector attached to the distribution panel, or the cable and
the line must be disabled in the /etc/inittab file and a non-modem line;
the CLOCAL option must be set to on.
The exerciser runs until a [CTRL-C] or a kill -15 pid is sent to the
A logfile for you to examine and then remove is created in the current
working directory; errors can be listed in the logfile.
You must specify the -l option followed by the lines to test. The line-n
arguments identify the lines to be tested. A maximum of 32 lines can be
tested at any one time. The line-n arguments are specified as names taken
from the /dev directory without the letters "tty." For example, if the /dev
directory lists tty03, the line-n argument is 03.
The Devices section lists the devices that can be tested.
If you want to run a system exerciser over an NFS link or on a diskless
system, there are some restrictions. For exercisers such as fsx(8) that
need to write into a file system, the target file system must be writable
by root. Also, the directory from which an exerciser is executed must be
writable by root because temporary files are written into the directory.
These restrictions can be difficult to adhere to because NFS file systems
are often mounted in a way that prevents root from writing into them. Some
of the restrictions may be adhered to by copying the exerciser into another
directory and then executing it.
Pseudo devices (devices whose first character after tty is any alphabetic
character, other than lowercase d) cannot be tested. Also lat devices with
major #5 cannot be tested.
Use the file command on /dev/tty* to find out which tty line corresponds to
a device line number.
1. The following example runs the cmx exerciser for 60 minutes on lines
00, 13, 22, and 32:
% /usr/field/cmx -t60 -l 00 13 22 32
2. The following example runs the cmx exerciser on lines 11, 42, 45, and
76 in the background until interrupted by a [CTRL-C] or a kill -15
% /usr/field/cmx -l 11 42 45 76 &
3. The following example runs the cmx exerciser on line 11, specifying a
range of baud rates to test.
% /usr/field/cmx -b9600-38400 -l 11
Commands: diskx(8), fsx(8), memx(8), shmx(8), tapex(8)
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