| Platform SDK: Memory |
The HeapLock function attempts to acquire the critical section object, or lock, that is associated with a specified heap.
If the function succeeds, the calling thread owns the heap lock. Only the calling thread will be able to allocate or release memory from the heap. The execution of any other thread of the calling process will be blocked if that thread attempts to allocate or release memory from the heap. Such threads will remain blocked until the thread that owns the heap lock calls the HeapUnlock function.
BOOL HeapLock( HANDLE hHeap // handle to heap );
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
The HeapLock function is primarily useful for preventing the allocation and release of heap memory by other threads while the calling thread uses the HeapWalk function.
Each call to HeapLock must be matched by a corresponding call to the HeapUnlock function. Failure to call HeapUnlock will block the execution of any other threads of the calling process that attempt to access the heap.
Note To guard against an access violation, use structured exception handling to protect any code that writes to or reads from a heap. For more information on structured exception handling with memory accesses, see Reading and Writing and Structured Exception Handling.
Windows NT/2000: Requires Windows NT 3.5 or later.
Windows 95/98: Unsupported.
Header: Declared in Winbase.h; include Windows.h.
Library: Use Kernel32.lib.
Memory Management Overview, Memory Management Functions, HeapUnlock, HeapWalk