craig@mstr.hgc.edu (craig chaiken) (10/04/90)
I have unsuccessfully attempted to execute INT 25H and 26H (read and write absolute disk sectors) from an INT 28H (DOS Idle) handler. Here is what happens: 1) The TSR loads successfully, and returns to the DOS prompt. 2) Additional commands may be entered without difficulty at this point. 3) A remote computer triggers the execution of an unlimited number of INT 25H or 26H functions without difficulty. 4) The host computer is allowed to sit dormant for a moment. 5) A user attempts to enter a command at the DOS prompt on the host. 6) The host computer's keyboard locks up, except for acknowledging <CapsLock>, <NumLock>, and <ScrollLock>. 7) The TSR stops processing requests. My guess is that INT 25H and 26H somehow corrupt DOS's keyboard handler stack (IOStack). The only solution I can think of is to rewrite INT 25H and 26H making certain to use a separate stack. If some MSDOS guru out there knows a better solution, I would greatly appreciate a hint. Craig Chaiken craig@mstr.hgc.edu