Operating systems courses tend to suck because they take the simplest of concepts and try to make them convoluted.
Documentation for the GetCurrentThread () function is
What it does not explain is that the return value for the function is a “handle.” Windoze uses handles somewhat as pointers to objects but where you cannot access the object directly.
So you call GetCurrent() thread and it returns a “Handle to the Thread.” That handle can then be used to do things with the thread.
Here are the things you can do:
https://learn.microsoft.com/en-us/windows/desktop/ProcThread/process-and-thread-functions
Some of these function pages have short examples.
So you could do:
print ("Thread ID: %d\n", GetThreadID (GetCurrentThread())) ;
and have the ID of the current thread.
solved WINDOWS API: GetCurrentThread(); in C [closed]