I was wondering if anyone knew a way to allow a shell command to run for a specific period of time.  In this particular case, I want tcpdump to run for 23 hours, 59 minutes, 59 seconds.  I couldn't find anything in the tcpdump man page that gave me the impression that tcpdump itself has that functionality.  And, I couldn't find anything in a quick google search.  I also thought it was an interesting scripting trick that I don't know, and thought I'd ask you nice folks...
-Erik