Provided by: inetutils-talk_1.9.4-8_amd64
talk — talk to another user
talk person [ttyname]
Talk is a visual communication program which copies lines from your terminal to that of another user. Options available: person If you wish to talk to someone on your own machine, then person is just the person's login name. If you wish to talk to a user on another host, then person is of the form ‘user@host’. ttyname If you wish to talk to a user who is logged in more than once, the ttyname argument may be used to indicate the appropriate terminal name, where ttyname is of the form ‘ttyXX’. When first called, talk sends the message Message from TalkDaemon@his_machine... talk: connection requested by your_name@your_machine. talk: respond with: talk your_name@your_machine to the user you wish to talk to. At this point, the recipient of the message should reply by typing talk your_name@your_machine It doesn't matter from which machine the recipient replies, as long as his login-name is the same. Once communication is established, the two parties may type simultaneously, with their output appearing in separate windows. Typing control-L ‘^L’ will cause the screen to be reprinted, while your erase, kill, and word kill characters will behave normally. To exit, just type your interrupt character; talk then moves the cursor to the bottom of the screen and restores the terminal to its previous state. Permission to talk may be denied or granted by use of the mesg(1) command. At the outset talking is allowed. Certain commands, in particular nroff(1) and pr(1), disallow messages in order to prevent messy output.
/etc/hosts to find the recipient's machine /var/run/utmp to find the recipient's tty
The version of talk(1) released with 4.3BSD uses a protocol that is incompatible with the protocol used in the version released with 4.2BSD.
The talk command appeared in 4.2BSD.