"Tailing" grep (Was: cat and grep without destroying file)

[Michael R. Head]

On Sun, 2007-09-30 at 17:04 -0500, Brian Fahrlander wrote:
> While we've got the attention of the most-able on this subject, I'd 
> like to reopen a discussion about a very similar tool: a 'grep' that 
> happens on tailing a file.  There have been dozens of times that I'm 
> looking for a message number in /var/log/mail.log and would love to see 
> only the lines mentioning that message.
> 
>      A couple of years ago I asked and got a "maybe you could write 
> something", but I actually never could.  It's not as easy as it looks.
> 
>      Any chance you guys have seen this done?

You can use the "watch" program to effectively achieve this
functionality.

watch "grep kernel /var/log/syslog | tail -n 20"

> -- 
>   ------------------------------------------------------------------------
>   Brian Fahrländer                 Christian, Conservative, and Technomad
>   Evansville, IN                              http://Fahrlander.net/brian
>   ICQ: 5119262                         AOL/Yahoo/GoogleTalk: WheelDweller
>   ------------------------------------------------------------------------
> 
-- 
Michael R. Head <burner at suppressingfire.org>
http://picasaweb.google.com/demiri.head.wedding