TerminateThread

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Windows Embedded CE 6.0 R3

4/8/2010

This function stops the specified thread.

Syntax

BOOL TerminateThread(
  HANDLE hThread,
  DWORD dwExitCode
);

Parameters

• hThread
  [in, out] Handle to the thread to terminate.

• dwExitCode
  [in] Specifies the exit code for the thread. To retrieve a thread's exit value, use the GetExitCodeThread function.

Return Value

Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.

Remarks

This function is used to cause a thread to exit. When this occurs, the target thread has no chance to execute user-mode code.

DLLs attached to the thread are notified that the thread is terminating.

It also terminates the thread's process only if the thread in question is the main or primary thread.

TerminateThread is a dangerous function. Use it only in the most extreme cases.

Call this function only if you know exactly what the target thread is doing and you control all code the target thread could be running at the time of the termination.

The following list shows examples of problems that can result by calling TerminateThread:

• 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.
• A thread cannot protect itself against TerminateThread other than by controlling access to its handles. The thread handle returned by the CreateThread function has THREAD_TERMINATE access, so any caller holding one of these handles can terminate your thread. The handle returned from CreateProcess can only be used for waiting or to query the exit code of the process or thread.

If the target thread is the last thread of a process when this function is called, the thread's process is also terminated.

The state of the thread object becomes signaled, releasing other threads waiting for the thread to terminate. The thread's termination status changes from STILL_ACTIVE to the value of the dwExitCode parameter.

Terminating a thread does not necessarily remove the thread object from the system. A thread object is deleted when the last thread handle is closed.

A thread cannot be terminated while making a system API call. When the API call is complete and the thread returns to the executing process's address space, it is terminated. If the thread never returns from a system API call, it is not terminated.

Requirements

See Also

Reference

Process and Thread Functions
CreateProcess
CreateThread
GetExitCodeThread

Other Resources