UNIX for Dummies Questions & Answers

I have a problem. I made a script (that I am very proud of - never scripted before) that kills off idle sessions based on who -u. The problem is it is killing sessions that aren't truly idle. who -u reports them as being idle for 7 hours, when in reality they have been using a program for that entire time. My users all run a separate program when they log in, I believe who -u is looking at tty idle time? As in when the user last entered a command on the command line? Is this true? If it matters, this is AIX 4. Thanks

Log in with a second session and test it yourself
I think it's somewhat dangerous to kill idle sessions. Usually a system is not having problems with multiple accounts being logged in. Did you encounter a technical problem or is it just to keep the system "clean" from those evil idlers? In AIX 4.3.3 I remember there was some limit to parallel session set to 256 which could be just set to a higher value.

No, it is just that the program we use to interact with our database (or it may be the database program itself - I'm not sure exactly) can only have 64 users on it any time. I am working on increasing that number but it is a money issue, its like $2,000 per license for each additional session.

If they use a separate program, we consider that as client. So if they connect via telnet or ssh, you will see them with who -u. Usually those separate programs using a database client and use their own protocol and don't show up in the OS with.
Usually you can list connections or applications in databases themselves (at least in DB2 I am able to). If this is the case, maybe have a script running there, disconnecting the sessions via the db's commands.

They either connect directly to the RS/6000 via RS232 over cat5, or telnet in to the RS/6000 with a terminal emulator (or I just use ms telnet), once they log in (they all use the same username to log into AIX) the profile for the user launches the program. Once inside the program they input their individual operator code and password and start working. I can see every connection with who -u and w. I ran my script and before I killed the sessions, I recognized my boss' IP address in the list of PID's about to be killed. who -u reported it as idle for 6 hours. He said he was doublevisioning (a remote control program for unix) to another machine and had not been idle for 6 hours at all. Is it possible to determine idle time based on physical keyboard input with shell scripting? Or will I have to learn C or some other high level language ><?

Ok, I see the problem now. Sorry, I have no idea then. I bet there is a possibility to write that in C, but which library to use etc... no idea, sorry. If I come up with an idea later, I will post it.