Python Programming On Win32

win32event Module

Each application has different synchronization requirements. Some programs may need to wait for threads to complete, while some threads may need to wait for a file operation to complete or mutexes to become available. To cater to these various requirements, Windows bases all its synchronization primitives around Windows HANDLES. When you wish to wait for something of significance, you usually pass a handle. For example, you can wait for a thread or process to complete by specifying its handle; you can wait for a file operation to complete by waiting on the handle in the OVERLAPPED object you specified. You can wait for the mutex, semaphore, event, or other objects by passing the handle you obtained when opening or creating the object. Thus, regardless of the type of object or event you are waiting for, you always use handles and can use the same Win32 functions.

There are three functions exposed by win32event that wait for Win32 objects: WaitForSingleObject(), WaitForMultipleObjects(), and MsgWaitFor-MultipleObjects(). Each of these functions allow you to wait for one or more handles to become signaled, but exactly what signaled means depends on the object. For example, a signaled synchronization object typically means you have acquired the object, a signaled thread or process handles mean the thread has terminated, and so forth.

Here are the three functions.

WaitForSingleObject()

As the name implies, this function allows you to wait for a single object to become ...