Hello, RussianFellow, you wrote: RF> for a suspension of performance of a flow it is necessary to use function SuspendThread, for continuation of performance of a flow - function ResumeThread. It is possible, but it is not necessary. It is better to send to a flow controlling commands - e.g. by "sending" (setting) . Events (NOT windows messages, and those that CreateEvent), or . The variables which value the flow will periodically check. RF> and how competently to destroy a flow in MFC? It is correct to complete flow operation - also as well as not on MFC, as well as in other systems/languages - to tell about it to a flow as - see above. RF> to me advised function TerminateThread Who advised? Result deliver here (c) it is not necessary to use TerminateThread. RF> but it has lacks - after its call the flow all the same occupies a stack of storage and has access to a kernel before the end. At it a heap of lacks, be not too lazy, is mandatory read TerminateThread And the flow stack perhaps the only thing that is released (there was truth a bug, read under the link: Windows Server 2003 and Windows XP: The target thread's initial stack is not freed, causing a resource leak.) Here to you : TerminateThread is a dangerous function that should only be used in the most extreme cases. You should call TerminateThread only if you know exactly what the target thread is doing, and you control all of the code that the target thread could possibly be running at the time of the termination. For example, TerminateThread can result in the following problems: If the target thread owns a critical section, the critical section will not be released. If the target thread is allocating memory from the heap, the heap lock will not be released. If the target thread is executing certain kernel32 calls when it is terminated, the kernel32 state for the thread's process could be inconsistent. If the target thread is manipulating the global state of a shared DLL, the state of the DLL could be destroyed, affecting other users of the DLL. + will not be caused local objects. + if you use MFC AfxBeginThread - any additional pieces, as well as itself CWinThread which creates MFC, also will not be released RF> And how competently to destroy a flow that at it after that destructions - that after that destructions this flow was not fulfilled, had no access to a kernel and did not occupy a storage stack? See above, at the very beginning of RF> There are functions AfxEndThread and ExitThread, caused in a stream function for its end. But how correctly to use them? It is not necessary for you to use them, simply do reset (return) of a stream function, and you will use see will not be caused local objects.