How to release the object in a TLS-slot at thread exit on Windows?

Question

for example, in a multi-thread program:

struct TLSObject;

void foo()
{
    TLSObject* p = TlsGetValue(slot);
    if (p == 0) {
        p = new TLSObject;
        TlsSetValue(slot, p);
    }
    // doing something with p
}

the first time to call foo() in any thread will makes a new TLSObject.

my question is: How to delete a TLSObject(if I don't use boost::thread and boost::thread_specific_ptr) ?

boost::thread_specific_ptr can do cleanup work at thread exit, but it depends on boost::thread I guess, not for normal OS thread, and it's slow.

Answer 1

Instead of TlsAlloc, use FlsAlloc (and related Fls* functions). With FLS, you register a cleanup callback which the OS will call on the thread before the thread terminates, giving you the opportunity to clean up.