InitOnceInitialize function (synchapi.h)

Initializes a one-time initialization structure.

void InitOnceInitialize(
  [out] PINIT_ONCE InitOnce
);

[out] InitOnce

A pointer to the one-time initialization structure.

None

The InitOnceInitialize function is used to initialize a one-time initialization structure dynamically. To initialize the structure statically, assign the constant INIT_ONCE_STATIC_INIT to the structure variable.

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

A one-time initialization object cannot be moved or copied. The process must not modify the initialization object, and must instead treat it as logically opaque. Only use the one-time initialization functions to manage one-time initialization objects.

The following example calls InitOnceInitialize to initialize the one-time initialization structure named InitOnce. Alternatively, the structure can be declared as a global variable as shown in Using One-Time Initialization.

//Requires Windows Vista, Windows Server 2008 or later
#define _WIN32_WINNT 0x0600

#include <windows.h>

BOOL StartInitialization()
{
    INIT_ONCE InitOnce;

    InitOnceInitialize(&InitOnce);

    //...
    return TRUE;
}

InitOnceExecuteOnce

One-Time Initialization

Synchronization Functions