I think in PT it just relies on your selections in the preferences window that Mac described.

However many you selected is how many tracks you will end up with.

Example- in preferences you select inputs 1&2, 3&4, and 5&6.
If you highlite a track to record on PT will record all six inputs and then when you are done recording it will just put them on the next available tracks. So if you recorded onto track 6, the rest will go onto 7 and 8 (assuming stereo tracks).

The real trick is to decide on whether to record to stereo track or mono track. Whatever you set the track as will determine how PT handles the inputs. In the above example if the track being recorded to is set to stereo, then the first two inputs go to that track (as left and right) and the next two go to the next available blank track and the last two go to the next available blank tracks so you end up with three stereo tracks.

However, if the track being recorded with is a mono track, PT will put the inputs on the next six available tracks a mono tracks.

So in the future you will have to be mindful of how many inputs are highlited in the preferences section, or you will spend time going back to delete blank tracks if you only wanted to record one stereo pair and had three pairs highlighted. This is because in PT the selections in the preferences input area set these parameters, not the port on the track... port on track is for output only, if my memory is serving me correctly (I used PT a LOT before Realband).

I do not work here, but the benefits are still awesome
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