IDEDOS 0.91+ only
Read ($DEF4) and write ($DEF1) support on modifiable files
IDEDOS 0.90 only allowed character I/O on modifiable files, but this limitation was fixed now. This opens up posibilities to create high performance database softwares, read/write image file support (D64) or IFFL system with fast read/write support.
I guess this will solve all my problems. I was looking for a confirmation on this, and now I've found it.