otalk username [ttyname]
The otalk command is an older version of talk that supports an older, architecture-dependent, version of the talk protocol. Whereas otalk only works between machines of the same architecture, talk supports a newer version of the talk protocol that can communicate with machines of different architectures.
If talk is unable to establish a connection to a particular machine, it may be the case that the target machine only supports the older, architecture-dependent, version of the talk protocol. If your machine and the target machine are of similar architecture, otalk may succeed where talk failed.
If you want to talk to a user who is logged in more than once, the ttyname argument may be used to indicate the appropriate terminal name.
When first called, talk sends the message:
Message from TalkDaemon@ her_machine at time . . . talk: connection requested by your_name@your_machine talk: respond with: talk your_name@your_machineto the user you want to talk to. At this point, the recipient of the message should reply by typing:
If a talk request is received from a machine using the architecture-dependent talk protocol, the message will instruct the user to respond with otalk instead of talk.
It does not matter from which machine the recipient replies, as long as the login name is the same. Once communication is established, the two parties may type simultaneously, with their output appearing in separate windows.
Typing <Ctrl><l> redraws the screen, while your erase, kill, and word kill characters will work in talk as normal. To exit, just type your interrupt character; talk then moves the cursor to the bottom of the screen and restores the terminal.
Permission to talk may be denied or granted by use of the mesg(1) command. At the outset talking is allowed. Certain commands, such as pr(1), disallow messages in order to prevent messy output.