From: Jonathan Nielsen <jonathan@...>
Date: 2010-01-15T11:03:18+09:00
Subject: Re: Notifying via Terminal in Linux

>> Is there something out there I can use to do this? I was thinking of
>> using the WALL command, but that seems sloppy and requires reading from
>> a file (for ubuntu).
>
> WALL command doesn't require reading from a file, it reads the STDIN.
>
> When you do "wall < FILE" you are redirecting the STDIN to the file, so the
> content of the file is passed to wall via STDIN.
>
> When you run "wall" (just "wall") you must insert text with the keyboard and
> press Ctrl+D to exist and deliver the message.
>
> So in Ruby you could redirect the STDIN (better $stdin) to invoke the system
> command (not sure now how to achieve it but sure it's possible).
>

Yes, use popen3 to get a reference to stdin of the wall process and
write into the stdin.  Should work anyway...

-Jonathan Nielsen