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The latest version of this topic can be found at __readeflags.
Reads the program status and control (EFLAGS) register.
Syntax
unsigned     int __readeflags(void);  
unsigned __int64 __readeflags(void);  
Return Value
The value of the EFLAGS register. The return value is 32 bits long on a 32-bit platform and 64 bits long on a 64-bit platform.
Remarks
These routines are available only as intrinsics.
Requirements
| Intrinsic | Architecture | 
|---|---|
__readeflags | 
x86, x64 | 
Header file <intrin.h>