GETTYD(8) BSD System Manager's Manual GETTYD(8)NAMEgettyd - manage serial devices
SYNOPSISgettyd [-a acct-file] [-b backlog] [-d] [-l log-file] [-r rule-file] [-s]
[-v]
DESCRIPTION
The gettyd daemon manages a pool of serial devices (lines). It selects
the lines to manage by reading the /etc/ttys file and searching for en-
tries which have manager set to gettyd (see ttys(5) and ttys.conf(5)).
Any line which has the dialin entry set will be conditioned by the script
defined by either condition or watcher. (Exactly one of these two entries
must be defined.) Any line which has the dialout entry set will be made
available for outgoing requests. Any line which has the dialout entry
but not the dialin entry will be conditioned by the script defined by
hangup.
The following options are available:
-b backlog By default gettyd will allow up to 64 outstanding re-
quests (see listen(2)). With the -b option use backlog
instead of 64.
-a acct-file Normally accounting records are written to
/var/account/gettyd but can be overridden by specifying
acct-file.
-d Run in debug mode. Do not automatically detach from the
controlling terminal. All messages are written to stan-
dard output rather than being written to the account
file, the logging file, or syslog(8).
-l log-file Normally verbose and debug messages are written to
/var/log/gettyd.log but can be overridden by specifying
log-file.
-r rule-file By default the dialing rules are read from
/etc/dialer.rules but can be overridden by specifying
rule-file.
-s Start in single user mode. Do not allow logins, but do
allow dialout requests. Lines which use watcher scripts
are not available for dialout when running in single user
mode.
-v Enable verbose mode. Detailed state change diagnostics
are entered into the log-file (or displayed on standard
output when the -d flag is specified).
The gettyd daemon makes the local domain socket /var/run/dialer available
for dialing requests. A request is a single line of ASCII which contains
a cgetent(3) like entry, followed by a newline. A typical entry for a
dialing request might be:
request:number=+1612555121|+16125552323:dte-
speeds=115200:speed=28800|14400:
When it receives a request, it first determines what type of request it
is. If the request starts with ``request:'' then gettyd searches for a
line that is available and that the requestor has proper permissions to
place the call. If a line is found, the requested number is dialed.
Once a connection is established with the remote side, gettyd passes back
the file descriptor associated with the attached line. If the client
which requested the connection closes its connection with , its access to
the line will be revoked, the connection dropped, and the line re-ini-
tialized.
The gettyd daemon can qualify a number (over even remap it) via a set of
rules defined the /etc/dialer.rules file (see dialer.rules(5)). Phone
numbers may also be provided in the format @name in which case name is
looked up in the /etc/phones file (see phones(5)).
The gettyd daemon currently understands two other types of requests. If
the request starts with ``status:'' then status about the serial lines is
returned on the socket. (The gettystat(8) program issues ``status'' com-
mands by default.) Normally status information is only returned for the
lines managed by gettyd. If the field ``:doall:'' is in the request, all
lines will be reported on. The request can be limited to specific lines
by listing the lines desired as field, for example:
status:tty01:tty02:
If the request starts with ``reset:'' then gettyd is reset depending on
the fields supplied. (The -r option to the gettystat command causes it
to issue a ``reset'' command.) Currently the only useful requests are:
reset:verbose: Enable verbose messages (same as -v).
reset:verbose=off:
reset:verbose@: Disable verbose messages (default)
reset:debug: Enable debug messages (same as -d, except the debug
messages go to the logfile).
reset:debug=off:
reset:debug@: Disable debug messages (default)
reset:multiuser: Enable logins (and reread /etc/ttys).
reset:reread: Cause gettyd to rescan /etc/ttys
reset:shutdown: Prevents gettyd from starting any new sessions.
reset:die: Cause gettyd to exit.
Normally these requests are made by init(8). When init(8) receives a
SIGHUP it sends the ``reread'' command to gettyd and a SIGTERM to init
causes it to send ``shutdown'' and then ``die'' to gettyd.
SEE ALSOdialer.rules(5), phones(5), ttys(5), ttys.conf(5), gettystat(8),
init(8), login(8)BSDI BSD/OS April 29, 1996 2
