8:mgetty
From Linux Man Pages
mgetty - smart modem getty
mgetty [options] ttydevice [gettydefs]
Contents |
DESCRIPTION
Mgetty is a ``smart getty replacement, designed to be used with hayes compatible data and data/fax modems.
Mgetty knows about modem initialization, manual modem answering (so your modem doesn't answer if the machine
isn't ready), UUCP locking (so you can use the same device for dial-in and dial-out). Mgetty provides very
extensive logging facilities.
This manpage doesn't try to detail mgetty setup in detail, it just lists the most important options. For detailed
instructions, see the info file mgetty.info (mgetty.texi).
OPTIONS
-k <space>
Tells mgetty to leave <space> kbytes free on disk when receiving a fax.
-x <debug level>
Use the given level of verbosity for logging - 0 means no logging, 9 is really noisy. The log file is usu-
ally /tmp/log_mg.<device>
-s <speed>
Set the port speed to use, e.g. "-s 19200".
-r Tells mgetty that it is running on a direct line. UUCP locking is done, but no modem initialization what-
soever.
-p <login prompt>
Use the given string to prompt users for their login names. Various tokens are allowed in this string.
These tokens are: @ for the system name, \n, \r, \g, \b, \v, \f, \t for newline, carriage return, bell,
backspace, vertical tab, form feed, and tab, respectively. \P and \L will expand to the tty name
("ttyS0"). \Y will give the Caller ID, \I the "CONNECT foobar" string returned by the modem, and \S will
output the port speed. \s, \m, \V, \R represent the operating system, the hardware name, the OS version,
the OS release. \N and \U give the number of users currently logged in. \C will be changed into the
result of ctime(), and \D and \T will output the date and time, respectively. Finally, \<digit> will use
digit as octal/decimal/hexadecimal representation of the character to follow.
The default prompt is specified at compile time.
-n # Tells mgetty to pick up the phone after the #th RING. Default is 1.
-R <t> Tells mgetty to go into "ringback" (aka "ring-twice") mode. That means: the first call is never answered,
instead the caller has to hang up after the phone RINGs, wait 30 seconds, and then call again in the next
<t> seconds for mgetty to pick up. If no call comes, mgetty will exit.
I do not really recommend using this, better get a second phone line for the modem.
-i <issue file>
Output <issue file> instead of /etc/issue before prompting for the user name. The same token substitutions
as for the the login prompt are done in this file.
-D Tells mgetty that the modem is to be treated as a DATA modem, no fax initalization is attempted.
-F Tells mgetty that DATA calls are not allowed and the modem should be set to Fax-Only.
-C <class>
Tells mgetty how to treat the modem. Possible values for <class> are "auto" (default, try to find out
whether the modem supports fax), "cls2" (use the class 2 fax command set, even if the modem supports class
2.0), "c2.0" (use the class 2.0 fax command set), "data" (data only, exactly as the -D switch).
-S <g3 file>
If a call comes in and requests fax polling, mgetty will send the named file. Note: not all fax modems
support poll sending.
-I <fax id>
Use the given fax station ID for fax identification. Not used for data modems.
-b Open the port in blocking mode. Best used in combination with "-r". This is the default if mgetty is
called as getty. You may want to use this if you want to make use of the two-device / kernel-locking
scheme of the Linux and SunOS operating systems (/dev/ttyS.. and /dev/cua..). I do not recommend it, it's
just include for completeness, and to be able to use mgetty as a full-featured getty replacement.
-a Use autobauding. That is, after a connection is made, mgetty parses the "CONNECT foo" response code of the
modem and sets the port speed to the first integer found after the "CONNECT" string, "foo" in this exam-
ple. You need this if your modem insist on changing its DTE speed to match the line speed. I recommend
against using it, better leave the port speed locked at a fixed value. The feature is included because
there exist old modems that cannot use a fixed (locked) port speed.
-m 'expect send ...'
Set the "chat sequence" that is used to initialize the modem. For an empty expect part, use empty double
quotes (""). Since the sequence contains spaces, you have to enclose all of it in single quotes(). Exam-
ple:
mgetty -m '"" ATH0 OK'
FILES
/etc/mgetty+sendfax/mgetty.config
Main configuration file.
/etc/mgetty+sendfax/login.config
controls whether (and when) mgetty should call some other program for user login instead of /bin/login.
How this is done is explained in this file.
/etc/mgetty+sendfax/dialin.config
controls acceptance/denial of incoming calls based on the caller's number. Available only if you have
"caller ID" and your modem supports it.
/etc/nologin.ttyxx
controls whether mgetty should pick up the phone upon incoming calls. If the file exists, calls are com-
pletely ignored. You can use this, for example, to stop mgetty during day time, and let it pick up at
night only, by creating and removing /etc/nologin.ttyxx via the cron program at the appropriate time.
/etc/issue
will be printed after a connection is established, and before the with the '-i' option.
/var/log/mgetty.ttyxx
Debug log file, see below.
DIAGNOSTICS
If mgetty doesn't work the way it should, the main source of diagnostic data is the log file. It can be found in
"/var/log/mgetty.ttyxx" (for the mgetty process handling "ttyxx"). If it doesn't contain enough details, enhance
the log level with the '-x' option to mgetty, e.g. "-x 5".
Many of the common problems and solutions are discussed in the mgetty manual and the FAQ. Please see the WWW
page at http://alpha.greenie.net/mgetty/ for both.
BUGS
Not all of mgetty configuration can be done at run-time yet. Things like flow control and file paths (log file /
lock file) have to be configured by changing the source and recompiling.
Users never read manuals...
RELATED
g32pbm(1), sendfax(8), getty(8), mgettydefs(4), mgetty.info