| void DirectedYield(htask) | |||
| HTASK htask; |
The DirectedYield function puts the current task to sleep and awakens the given task.
htask
Specifies the task to be executed.
This function does not return a value.
When relinquishing control to other applications (that is, when exiting hard mode), a Windows-based debugger should call DirectedYield, identifying the handle of the task being debugged. This ensures that the debugged application runs next and that messages received during debugging are processed by the appropriate windows.
The Windows scheduler executes a task only when there is an event waiting for it, such as a paint message, or a message posted in the message queue.
If an application uses DirectedYield for a task with no events scheduled, the task will not be executed. Instead, Windows searches the task queue. In some cases, however, you may want the application to force a specific task to be scheduled. The application can do this by calling the PostAppMessage function, specifying a WM_NULL message identifier. Then, when the application calls DirectedYield, the scheduler will run the task regardless of the task's event status.
DirectedYield starts the task identified by htask at the location where it left off. Typically, debuggers should use TaskSwitch instead of DirectedYield, because TaskSwitch can start a task at any address.
DirectedYield returns when the current task is reawakened. This occurs when the task identified by htask waits for messages or uses the Yield or DirectedYield function. Execution will continue as before the task switch.
DirectedYield is located in KRNL286.EXE and KRNL386.EXE and is available in Windows versions 3.0 and 3.1.