#1 Burning Software

I'm using fn TrackAtOnceFromTree for adding files to data disc. But when user selects file that fills all free empty disc space, then i want switch mode to DiscAtOnce. So, what mode i must use for normal data disc ? I think that is no matter in this case, but which mode is better for files backup when recorder supports both modes ?

Second question: how many data i can overburn in DAO mode, so it will be safe for any recorder ? 15 MB or less ?

RAW modes (Disc-At-Once and RAW Session-At-Once) are usually considered as more "professional" modes for burning CDs. If you're not afraid to have your code a bit more complex (use different burning modes for CDs and DVDs and have a selection of modes for CDs) you can stick with SAO or DAO. Or let the user to pick up the one works for him in the best way

It (overburn size) can be much more. Depends of 1) media type -- different discs of the same labeled size have different overburning capabilites 2) overburn inplementation on particular burning device.

If you're dealing with backups I'd recommend you to stay away from overburns. B/s tails of the disc can be produced non-readable or partially readable or readable with errors. Maybe even not from the very beginning (disc is OK for half a year and then you'll get ECC errors during reads).

We'll be done with DVD burning engine refactored and then I'll add some advanced functions to determine overburn size and overburn modes. So you'll have a great field for experiments

Thanks for this.

And sorry - i sended not completed question I want know, what DAO mode (PQ/RawPW) is best for data backups. Somewhere i readed, that diffrence is about additional bytes of information (CDText and other) and something about error correction. So whats better ? DAO-PQ or DAO-RawPW ?

They are absolutely identical from the point of view of user data. In both modes 2352 raw sector is written. The only difference is -- subchannel data (16 bytes for PQ and 96 bytes for raw P-W mode) written. However most of the modern devices support only raw P-W mode so I guess this is what you may wish to stick with