There's a question over at audio.SE at the moment and I thought it may attract some answers here. I asked the user and he's happy to have it posted here to see if anyone has some ideas. Here it is verbatim:
I'm working with a client who needs to minimize the time between when recording is done and when the finalized audio CD ejects from the drive.
All of the computer recording software I'm aware of will generate a file which can then be burned to an Audio CD. I know there is external hardware I could buy that would burn an analog stream directly to disc, but I'm wondering if any software exists that can achieve this with a computer's internal optical drive. Ideally for Mac, though if it only exists for Windows or Linux I would be interested to hear about it.
(Other alternatives have been explored; I would much rather not deal with optical media at all, but this is a highly specialized situation.)
As to the source: "It would likely be an external USB audio interface."
If you need more info let me know.