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The latest version of this topic can be found at __readcr0.

Microsoft Specific**

Reads the CR0 register and returns its value.

unsigned long __readcr0(void);  /* X86 */  
unsigned __int64 __readcr0(void);  /* X64 */  

The value in the CR0 register.

__readcr0x86, x64

Header file <intrin.h>

This intrinsic is only available in kernel mode, and the routine is only available as an intrinsic.

Compiler Intrinsics