how to schedule terminating a running application with alarm clock

What you wanna do exactly?

I would use killall command for that, the use is killall process-name, "killall totem" for instance.

Maybe you can put that command on the action tab of alamclock.

Also this console command should work:

sleep 8h && killall totem

-sleep waits for the specified amount of time,time may be given as 15s for seconds 15m for minutes 15h for hours or 15d for days.
-&& tells the interpreter to wait till the first command finished and then executes the second
-"killall totem" kills totem.
So the above command waits for the given amount of time and then closes totem.

Hope it helps

kill winamp all did not work

Can you tell us what you wanna do exactly?
and, why winamp?
there is a wonderful world of native players on ubuntu repositories , if is the matter, I think that xmms is compatible with winamp plugins.

i use shout cast to broadcast live audio on internet

I'm assuming that your are running winamp trough wine, is that right?
You can use icecas2 for broadcasting live audio.I think is compatible with southcast's servers.also there is a linux native solution from nullsoft, have you tried it?

yes, you are right i am using win amp through wine. how do i use icecas2 pl. tell me how do i use it to broadcast live audio?

and pl. also tell me the linux native solution from nullsoft..i have not tried it yet.

sometimes winamp hangs so i am ready for a better option

Tell me more about what you are doing so I can advice you the best option;
Are you running the southcast's server in your house or you have an internet server for doing so?
Also, how do you play music?playlist in winamp or mixing in live?

i broad cast live sound to a server over the net

Take a look at synaptic searching for "shoutcast" You will find serveral programs.
I have tried two of them:
darksnow - is a gui for darkice, which streams the computer's line-in to a shouthcast/icecast server

idjc - This program is more like "atomix" it has 2 decks for mixing music and a jingle table, also streams to shoutcast./Icecast