View Full Version : What does BDOS function 36 do?

February 21st, 2018, 04:34 PM
When you set the r0/r1/r2 in the FCB directly before a randread or randwrite, what does BDOS function 36 do that isn't already being done?

February 21st, 2018, 04:55 PM
That function essentially reports your current position in a file, assuming you have been accessing it sequentially up till now. It is used to switch from sequential to random access, or possibly to simply compute the random record number for your current position (e.g. if building an index). If you are already accessing it randomly, I don't think it serves any purpose.