Release Current Virtual Machine's Time Slice

Called by a client program to indicate that the program is idle (for example, waiting for keyboard input). This allows the DPMI host to pass the CPU to other clients, or take power-conserving measures on laptop and notebook computers.

Call With

AX = 1680H

Returns

If function supported by host:
AL = 0

If function not supported by host:
AL = unchanged (80H)

Notes

This function is not specific to DPMI hosts. Some operating systems will recognize this call for programs running in real mode. Programmers are encouraged to use this call in all DOS and DPMI-client programs. All DPMI hosts will hook Int 2FH and so a DPMI client can use this API without any other precautions. Non-DPMI programs that can run on DOS 2.xx or earlier should make sure that the Int 2FH vector is non-zero before executing the Int 2FH.
When an application calls this function it will regain control at intervals, so it should continue to re-issue this function call so long as it has nothing to do.
DPMI client and application vendors are encouraged to use this function. It can significantly improve the performance of a DOS-based multitasking host.