GetActiveProcessorCount function (winbase.h)

Returns the number of active processors in a processor group or in the system.

Syntax

DWORD GetActiveProcessorCount(
  [in] WORD GroupNumber
);

Parameters

[in] GroupNumber

The processor group number. If this parameter is ALL_PROCESSOR_GROUPS, the function returns the number of active processors in the system.

Return value

If the function succeeds, the return value is the number of active processors in the specified group.

If the function fails, the return value is zero. To get extended error information, use GetLastError.

Remarks

To compile an application that uses this function, set _WIN32_WINNT >= 0x0601. For more information, see Using the Windows Headers.

Requirements

Requirement	Value
Minimum supported client	Windows 7 [desktop apps only]
Minimum supported server	Windows Server 2008 R2 [desktop apps only]
Target Platform	Windows
Header	winbase.h (include Windows.h)
Library	Kernel32.lib
DLL	Kernel32.dll