Fiber/Thread Local Storage
Over the course of professional development you run into extremely helpful functions in the Windows API. Today I ran into a set of functions that allow for storing a value specific to each thread. See the following link for a description of how to use thread local storage.
Note that a fiber runs in the context of the scheduling thread. Each thread may have multiple fibers and each fiber may have its own local storage. If a thread only has one fiber, then thread and fiber local storages are identical. For more information about fibers:
Now, to the more interesting part, using the APIs. Luckily, using the local storage is straight forward.
Process for using a local storage:
- Initialize local storage to retrieve index using TlsAlloc()
- Set values in local storage using TlsSetValue()
- Retrieve values using TlsGetValue()
Allocate the thread local storage once for all threads. Each thread uses the same index to set and retrieve values.
The first MSDN link has a great explanation on thread local storage.