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oldlinux-files/Linux-0.98/Yggdrasil-0.98.3/usr/man/man8/agetty.8
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.TH AGETTY 8
.ad
.fi
.SH NAME
agetty
\-
alternative System V/SunOS 4 getty
.SH SYSTEM V SYNOPSIS
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agetty [-i] [-l login_program] [-m] [-t timeout] port baud_rate,...
.SH SUNOS 4 SYNOPSIS
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agetty [-h] [-l login_program] [-m] [-t timeout] baud_rate,... port
.SH DESCRIPTION
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\fIagetty\fP opens a tty port, prompts for a login name and invokes
the /bin/login command. It is normally invoked by \fIinit(8)\fP.
\fIagetty\fP has several \fInon-standard\fP features that are useful
for hard-wired and for dial-in lines:
.IP o
Adapts the tty settings to parity bits and to erase, kill,
end-of-line and uppercase characters when it reads a login name.
The program can handle 7-bit characters with even, odd, none or space
parity, and 8-bit characters with no parity. The following special
characters are recognized: @ and Control-U (kill); #, DEL and
back space (erase); carriage return and line feed (end of line).
.IP o
Optionally deduces the baud rate from the CONNECT messages produced by
Hayes(tm)-compatible modems.
.IP o
Optionally does not hang up when it is given an already opened line
(useful for call-back applications).
.IP o
Optionally does not display the contents of the \fI/etc/issue\fP file
(System V only).
.IP o
Optionally invokes a non-standard login program instead of
\fI/bin/login\fP.
.IP o
Optionally turns on hard-ware flow control (SunOS 4 only).
.PP
This program does not use the \fI/etc/gettydefs\fP (System V) or
\fI/etc/gettytab\fP (SunOS 4) files.
.SH ARGUMENTS
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.TP
port
A path name relative to the \fI/dev\fP directory. If a "-" is
specified, \fIagetty\fP assumes that its standard input is
already connected to a tty port and that a connection to a
remote user has already been established.
.sp
Under System V, a "-" \fIport\fP argument should be preceded
by a "--".
.TP
baud_rate,...
A comma-separated list of one or more baud rates. Each time
\fIagetty\fP receives a BREAK character it advances through
the list, which is treated as if it were circular.
.sp
Baud rates should be specified in descending order, so that the
null character (Ctrl-@) can also be used for baud rate switching.
.SH OPTIONS
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.TP
-h (SunOS 4 only)
Enable hardware (RTS/CTS) flow control. It is left up to the
application to disable software (XON/XOFF) flow protocol where
appropriate.
.TP
-i (System V only)
Do not display the contents of \fI/etc/issue\fP before writing the
login prompt. Terminals or communications hardware may become confused
when receiving lots of text at the wrong baud rate; dial-up scripts
may fail if the login prompt is preceded by too much text.
.TP
-l login_program
Invoke the specified \fIlogin_program\fP instead of /bin/login.
This allows the use of a non-standard login program (for example,
one that asks for a dial-up password or that uses a different
password file).
.TP
-m
Try to extract the baud rate the \fIconnect\fP status message
produced by some Hayes(tm)-compatible modems. These status
messages are of the form: "<junk><speed><junk>".
\fIagetty\fP assumes that the modem emits its status message at
the same speed as specified with (the first) \fIbaud_rate\fP value
on the command line.
.sp
Since the \fI-m\fP feature may fail on heavily-loaded systems,
you still should enable BREAK processing by enumerating all
expected baud rates on the command line.
.TP
-t timeout
Terminate if no user name could be read within \fItimeout\fP
seconds. This option should probably not be used with hard-wired
lines.
.SH SYSTEM V EXAMPLES
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This section shows sample entries for the \fI/etc/inittab\fP file.
For a hard-wired line:
.ti +5
t0:2:respawn:/etc/agetty ttyM0 9600
For a dial-in line with a 2400/1200/300 baud modem:
.ti +5
t1:2:respawn:/etc/agetty -mt60 ttyM1 2400,1200,300
.SH SUNOS 4 EXAMPLES
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This section show sample entries for the \fI/etc/ttytab\fP file.
Note that init(8) appends the port name to the command
specified in the inittab file.
For a hard-wired line:
.ti +5
ttya "/usr/etc/agetty 9600" vt100 on local
For a dial-in line with a 2400/1200/300 baud modem:
.ti +5
ttyb "/usr/etc/agetty -mt60 2400,1200,300" unknown on modem
The latter also requires that the \fIDTR\fP and \fICD\fP modem
control lines are enabled (see the eeprom(8) manual page).
.SH FILES
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/etc/utmp, the system status file (System V only).
/etc/issue, printed before the login prompt (System V only).
/dev/console, problem reports (if syslog(3) is not used).
/etc/inittab (System V init(8) configuration file).
/etc/ttytab (SunOS 4 init(8) configuration file).
.SH BUGS
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The baud-rate detection feature (the \fI-m\fP option) requires that
\fIagetty\fP be scheduled soon enough after completion of a dial-in
call (within 30 ms with modems that talk at 2400 baud). For robustness,
always use the \fI-m\fP option in combination with a multiple baud
rate command-line argument, so that BREAK processing is enabled.
The text in the /etc/issue file (System V only) and the login prompt
are always output with 7-bit characters and space parity.
The baud-rate detection feature (the \fI-m\fP option) requires that
the modem emits its status message \fIafter\fP raising the DCD line.
.SH DIAGNOSTICS
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Depending on how the program was configured, all diagnostics are
written to the console device or reported via the syslog(3) facility.
Error messages are produced if the \fIport\fP argument does not
specify a terminal device; if there is no /etc/utmp entry for the
current process (System V only); and so on.
.SH AUTHOR(S)
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W.Z. Venema <wietse@wzv.win.tue.nl>
Eindhoven University of Technology
Department of Mathematics and Computer Science
Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
.SH CREATION DATE
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Sat Nov 25 22:51:05 MET 1989
.SH LAST MODIFICATION
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91/09/01 23:22:00
.SH VERSION/RELEASE
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1.29