Mkey V8.1.2Build 11 Version Free 60lkjh: The Ultimate Guide to Modem Unlocking
The constant is usually something like 0, 1, 4, or 5 (the last two being some high ascii printable digit). Or, if you really wanted to, you could write s + 10 as your increment.
Mkey V8.1.2Build 11. version free 60lkjh
But the idea is that this still might cause a problem, so other threads might see the same stale value of free_slots and try to access it. To solve this race condition, people use some kind of lock or fence to resolve it. When a thread is waiting for the lock to be released, the operating system flushes its thread-specific cache to main memory and sets free_slots to 0 to lock it:
The problem is that this is a lot less efficient than just having a single atomic operation and having a mutex object instead of using the operating system flushing the cache. So before you retry calling this, make sure that you really have a race condition. Thread A is reading free_slots, finds it is 0, tries to copy it, and then goes and locks it. Thread B is waiting for a lock to be released, and goes ahead and copies free_slots, finding that it is 0, and unlocks it.
The free_slots variable will be set to 0 if a thread unlocks it and the operating system has already flushed the memory to the main memory. So this is a very old trick, known as the false sharing race: