.\" This file Copyright (C) 1994 Jeff Tranter
.\" (Jeff_Tranter@Mitel.COM)
.\" It may be distributed under the GNU Public License, version 2, or
.\" any higher version.  See section COPYING of the GNU Public license
.\" for conditions under which this file may be redistributed.
.TH STATSERIAL 1 "17 December 1994" "Linux" "User Commands"
.SH NAME
statserial \- display serial port modem status lines

.SH SYNOPSIS

statserial [-n |  -d | -x] <device-name>

.SH DESCRIPTION

.B Statserial
displays a table of the signals on a standard 9-pin or 25-pin serial
port, and indicates the status of the handshaking lines. It can be
useful for debugging problems with serial ports or modems.

The optional
.B device-name
parameter is the full name of the device file for the serial
port in question. If not specified, the default is taken from the 
environment variable MODEM if set, otherwise /dev/ttyS0.

.PP
.SH "COMMAND\-LINE OPTIONS"

Each of the command line options is mutually exclusive.

.TP 0.5i
.B -n
Normally
.B statserial
will loop continuously, updating the status at one second intervals;
you can exit using Control-C. The -n option disables looping.

.TP 0.5i
.B -d

With this option the status of the modem is printed as a decimal
number. The bits are encoded as follows (XXX indicates unused bits):

.br
+---+---+---+---+---+---+---+---+---+
.br
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
.br
+---+---+---+---+---+---+---+---+---+
.br
|DSR|RI |DCD|CTS|XXX|XXX|RTS|DTR|XXX|
.br
+---+---+---+---+---+---+---+---+---+

.TP 0.5i
.B -x
This option is the same as -d, except that the output is in
hexadecimal.

.SH BUGS/LIMITATIONS
.PP

.B Statserial
only works with devices that support the TIOCMGET ioctl.

You need permission to read the device file.

The device file may be locked if other applications are using it.

.SH AUTHOR
.B Statserial
was written by Jeff Tranter (Jeff_Tranter@Mitel.COM), later updated by 
Frank Baumgart (godot@uni-paderborn.de) and is released under the 
conditions of the GNU General Public License.  See the file COPYING and 
notes in the source code for details.

.SH SEE ALSO

setserial(8) stty(1)
.br
/usr/src/linux/drivers/char/serial.c
/usr/include/linux/termios.h