NtGetCurrentProcessorNumberEx - NtDoc

#ifndef _NTPSAPI_H
// Threads
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_WIN7)

NTSYSCALLAPI
ULONG
NTAPI
NtGetCurrentProcessorNumberEx(
    _Out_opt_ PPROCESSOR_NUMBER ProcessorNumber
    );

#endif
#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
ULONG
NTAPI
ZwGetCurrentProcessorNumberEx(
    _Out_opt_ PPROCESSOR_NUMBER ProcessorNumber
    );

#endif
View code on GitHub