You can do a pause from the taskbar by selecting “suspend all active tasks”, from the menu. There may be a way to do that from the floating window too, but I don’t use it so I dunno.
A part of this conflict is the AV’s fault. I’ve seen the conflict you’re talking about, where the AV deletes the file, BC re-downloads it, AV deletes it again, etc.
It would be much better if the command-line AV could be told to halt on detection of an infection. Some of them do or can be told to. In that case control stays with the av’s error report, and BC is in a suspended state for that task until the AV window closes.
Some very popular AV’s lack this feature, alas.
What you can do depends on your AV’s capabilities. First check into whether it can do this halt thing. The first thing to try is BitComet’s “autodetect” function for antivirus. It may know what parameters to use and will automatically insert them. Or there may be a pause function available, but BC doesn’t know about it. You can insert that parameter yourself.
If you’re attached to the AV you’ve got, explore the command line options, then edit the av scan command in your BC options to include whatever you decided.
Most command-line functions should at least return a DOS errorlevel. That means you can write a batch program that mimics the halt function. Yeah. Well, it can be done, anyway. Just find a DOS batch programmer anymore.
I think you’d have much better luck pushing from the other end, insisting that your favorite AV’s vendor include the “pause on infection” feature in their CLI. It shouldn’t be BC’s job to accommodate all kinds of different behaviors. This ought to be standardized.
But on your next point. no bittorrent client does or can stop port operations immediately. They cannot. They can stop sending operations, but traffic will continue to arrive from other peers in the swarm, for as long as it takes those peers to get word that you are no longer in the swarm. That can easily take an hour or more until everybody successfully rescrapes the tracker and gets an updated metafile with you no longer listed. This doesn’t prevent you from shutting BC down. But those packets will continue to arrive. They’re harmless.