1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd December 11, 1993 29.Dt TALKD 8 30.Os 31.Sh NAME 32.Nm talkd 33.Nd remote user communication server 34.Sh SYNOPSIS 35.Nm 36.Sh DESCRIPTION 37The 38.Nm 39utility 40is the server that notifies a user that someone else wants to 41initiate a conversation. 42It acts as a repository of invitations, responding to requests 43by clients wishing to rendezvous to hold a conversation. 44In normal operation, a client, the caller, 45initiates a rendezvous by sending a 46.Tn CTL_MSG 47to the server of 48type 49.Tn LOOK_UP 50(see 51.In protocols/talkd.h ) . 52This causes the server to search its invitation 53tables to check if an invitation currently exists for the caller 54(to speak to the callee specified in the message). 55.Pp 56If the lookup fails, 57the caller then sends an 58.Tn ANNOUNCE 59message causing the server to 60broadcast an announcement on the callee's login ports requesting contact. 61.Pp 62When the callee responds, the local server uses the 63recorded invitation to respond with the appropriate rendezvous 64address and the caller and callee client programs establish a 65stream connection through which the conversation takes place. 66.Sh SEE ALSO 67.Xr talk 1 , 68.Xr write 1 69.Sh HISTORY 70The 71.Nm 72utility appeared in 73.Bx 4.3 . 74