ReliabilityContractAttribute

[HosamAly]

Hello, I am trying to understand the CER feature, but I am not very confident that I understand it well. I have read a number of articles about it, but I still need to check whether I understand it correctly. I hope you could help me. First, I apologize for this long post. I thought it is necessary to clarify my question. I'm thankful for your patience. I am implementing a SafeHandle, and the release code looks like this:

class MySafeHandle : SafeHandle {
protected override bool ReleaseHandle() {
MyClass.freeHandle(handle);
return !MyClass.CheckErrors(false);
}
}
class MyClass {
internal static extern void freeHandle(MySafeHandle handle);
internal static extern bool checkExternalErrors();

internal static bool CheckErrors(bool throwExceptionOnError) {
    if (!checkExternalErrors()) return false;
    if (throwExceptionOnError) throw new Exception();
    return true;
}

}

I'm not sure what to label freeHandle, checkExternalErrors and CheckErrors. freeHandle wouldn't tell whether there is an error; I have to call CheckErrors for that. But it will never throw an exception either, so I'm thinking it should be labeled [Cer.Success]. Meanwhile, CheckErrors may throw an exception, depending on the throwExceptionOnError parameter. So I think this should be labeled [Cer.MayFail]. But I don't really know... wouldn't that violate the CER on ReleaseHandle? Also what should I label checkExternalErrors? Does it not need a label? Or does it still need [ReliabilityContractAttribute(Consistency.WillNotCorruptState)]? I really feel confused! Thanks a lot for your patience! Even if you don't answer, I'm grateful that you read this post to the end. :)