C6329

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The latest version of this topic can be found at C6329.

warning C6329: Return value for a call to <function> should not be checked against <number>

The program is comparing a number against the return value from a call to CreateFile. If CreateFile succeeds, it returns an open handle to the object. If it fails, it returns INVALID_HANDLE_VALUE.

This code could cause the warning:

if (CreateFile() == NULL)  
    {  
        return;  
    }  

This code corrects the error:

if (CreateFile() == INVALID_HANDLE_VALUE)  
    {  
        return;  
    }