Okay, I'll give this a shot; it appears you're looking for the logic, and not the code (which is good, because I'm not that good at Perl yet :). Anyway, here's my attempt at pseudocoding your problem:

my ($starttime, $isopen, $totaltime) = (0, 0, 0);
while (<TIMELOG>) {
   if (/open$/) {
      next if $isopen;
      $isopen = 1;
      $starttime = getseconds($_);
   }
   elsif (/hold$/ || /closed$/) {
      next unless $isopen;
      $isopen = 0;
      $totaltime += getseconds($_) - $starttime;
   }
}
[download]

Well, that came out a bit closer to code than I had intended... oh well. I hope that helps.

Update: (1000 CDT 09 Jun) It occurred to me a bit more explanation might be in order. Basically, as I understand it, the key to your problem is to keep track of the first time you noticed the ID was in an open state, and only perform the addition to $totaltime when the ID moves out of the open state (and presumably, into one of the closed or hold states).

Also, having watched a bit of the CB discussion on this topic, I noticed that you want to run this in realtime. If that's the case, you may want to generate a fake log entry to be processed at the end with the current time and a non-open state to force the calculation of the open time. This would change the code to be more like this:

@lines = <TIMELOG>;
push @lines, makefake(time(), "closed");
for (@lines) {
   # Same loop body
}
[download]

Update #2: Edited code and above comments on real time about current state.

I know it might not be the optimal method to do it, but it seems as if it should get the job done (if I understand the job to be done correctly). Try it out - if it doesn't work, let me know. If it does, let me know then, too - I never know when I might need this bit of code. :)

CheeseLord