Executes the specified function successfully one time. No other threads that specify the same one-time initialization structure can execute this function while it is being executed by the current thread.

Syntax

BOOL WINAPI InitOnceExecuteOnce(
  __inout      PINIT_ONCE InitOnce,
  __in         PINIT_ONCE_FN InitFn,
  __inout_opt  PVOID Parameter,
  __out_opt    LPVOID *Context
);

Parameters

InitOnce [in, out]

A pointer to the one-time initialization structure.

InitFn [in]

A pointer to an application-defined InitOnceCallback function.

Parameter [in, out, optional]

An optional parameter to be passed to the callback function.

Context [out, optional]

A pointer to the data stored with the one-time initialization structure upon success. The low-order INIT_ONCE_CTX_RESERVED_BITS bits of the data must be zero.

Return Value

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.

Remarks

This function is used for synchronous one-time initialization. For asynchronous one-time initialization, use the InitOnceBeginInitialize function with the INIT_ONCE_ASYNC flag.

To compile an application that uses this function, define _WIN32_WINNT as 0x0600 or later. For more information, see Using the Windows Headers.

Examples

For an example that uses this function, see Using One-Time Initialization.

Requirements

See Also

InitOnceCallback

InitOnceInitialize

One-Time Initialization

Synchronization Functions

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Build date: 2/4/2010