Wow64EncodeApcRoutine - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers

#ifndef _NTPSAPI_H
//
// Threads
//
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * Encodes an APC routine pointer for use in a WOW64 environment.
 *
 * \param ApcRoutine The APC routine pointer to be encoded.
 * \return PVOID The encoded APC routine pointer.
 */
#define Wow64EncodeApcRoutine(ApcRoutine) \
    ((PVOID)((0 - ((LONG_PTR)(ApcRoutine))) << 2))

#endif
#endif
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This macro encodes the function pointer and indicates to NtQueueApcThread, NtQueueApcThreadEx, or NtQueueApcThreadEx2 that the APC should be executed in the WoW64 mode.

To decode the pointer back, use Wow64DecodeApcRoutine.

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See also