NAME
gtalkd - GNU talk daemon
SYNOPSIS
gtalkd [ -bfghsStv --version ]
DESCRIPTION
gtalkd is a talk daemon which is fully compatible with ntalkd which is
the BSD talk daemon. gtalkd provides a talk service via the internet.
A user may use a talk client to send a UDP message to gtalkd which will
then provide the services of storing invitations, and making
announcements to a user’s terminal.
Command line switches are:
-b, --bsd
Emulate the BSD post 4.2 talk protocol by not accepting any GNU
talk protocol extensions.
-f, --forever
Open a socket and loop on it forever. Unlike running under
inetd during which stdin and stdout provides the socket
necessary for communication, this option lets the talk daemon
run as a separate self supporting process.
-g, --gnu
Run using the GNU talk protocol extensions. This is the
default.
-h, --help
Print process help.
-s, --sun
Simulate the pre BSD 4.2 talk protocol which is commonly found
on SunOS and Solaris.
-S, --sunforward
This option is run as an extended option for the --sun option.
Instead of acting as a daemon and answering requests, all
requests are sent to the n/gtalk daemon on the same machine.
Answers are received and forwarded back the the requester.
-t, --tty
Send all error and verbose messages to the controlling TTY. In
addition, create and bind the correct socket by hand instead of
inheriting it through stdin and stdout.
-v, --verbose
Print out verbose information, or verbose syslog information.
--version
Print out the current version of gtalkd.
INSTALLATION
The GNU talk daemon can be placed in a system bin such as /usr/sbin or
/usr/local/sbin and then installed in the inetd.conf file in place of
the normal talk daemon which may be found there. The resulting
configuration in inetd.conf should contain the following lines:
talk dgram udp wait root /usr/sbin/tcpd /sbin/gtalkd -Ss
ntalk dgram udp wait root /usr/sbin/tcpd /sbin/gtalkd
In addition, if you are installing on SunOS or Solaris, you will have
to make it aware of the ntalk service. This service is found in
/etc/services. Simply find the line which says:
talk 517/udp
and add the line
ntalk 518/udp
right after it.
FILES
/etc/inetd.conf
Contains definitions for the Internet Super Server to start
gtalkd.
/etc/services
This file contains information relating names socket/service
information to names. It is used to determine the "[n]talk"
socket used when in forever mode.
/etc/passwd
Accessing /etc/passwd in the usual way allows gtalkd to
determine a users home directory to read their personal ringer
file. The ringer file allows gtalkd to forward announcements
directly to an interested process.
~/.ringer
Different individuals may start applications which create and
manage this file. The file contains a UDP socket definition
which allows gtalkd to automatically pass the announcement
information directly to a process which cares.
~/.talkfilter
This is read by gtalkd to determine of a pattern matches an
incomming call for the callee. If it does, then the requested
response is returned. A pattern is of the form
username@hostname DENY_METHOD
The username is a string which must match the incomming caller’s
id exactly. The hostname can be a substring of the caller’s
host name to match. One of username or hostname can be blank,
which conflicts defaulting first to username only matches, and
then to complete username,hostname combinations.
Valid DENY_METHODS are ALLOW , which allows a pattern to
announce to you, and NOT_HERE , which cause gtalkd to predent
you are not logged on. In addition, FAILED sends a failure
message, and PERMISSION_DENIED pretends that you have
permissions turned off on your tty. Lastly, SELECTIVE_REFUSAL
means to send a specific message back saying that you have
chosen to specifically prevent that person from calling you. If
their client is not GTALK compliant, then it is downgraded to
PERMISSION_DENIED
/etc/utmp, /var/adm/utmp
Different locations of utmp which contain login information for
different users. This file is referenced to determine which TTY
device to open in order to write an announcement message.
/dev/tty*
Terminal devices users are attached to. These devices are
opened in order to write an announcement message.
AUTHOR
Eric M Ludlam <zappo@gnu.org>
BUGS
Report bugs to <zappo@gnu.org>. This system has never been tested in a
high volume situation due to my limited resources.
COPYRIGHT
Copyright © 1995, 1996 Eric M. Ludlam Copyright © 1997 Free Software
Foundation.
AVAILABILITY
The newest version of gtalkd can be found within the etalk
distribution. As of the writing of this manual, it can be found on
ftp.ultranet.com:/pub/zappo/gtalk-*.tar.gz
SEE ALSO
inetd(8),talk(1),etalk(1),xphone(1)