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

/**
 * Retrieves the number of the current processor.
 *
 * \param ProcessorNumber An optional pointer to a PROCESSOR_NUMBER structure that receives the processor number.
 * \return ULONG The number of the current processor.
 * \sa https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/ntddk/nf-ntddk-kegetcurrentprocessornumberex
 */
NTSYSCALLAPI
ULONG
NTAPI
NtGetCurrentProcessorNumberEx(
    _Out_opt_ PPROCESSOR_NUMBER ProcessorNumber
    );

#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
ULONG
NTAPI
ZwGetCurrentProcessorNumberEx(
    _Out_opt_ PPROCESSOR_NUMBER ProcessorNumber
    );

#endif
View code on GitHub