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c++hexunsigned-integer

Comparing 8 - bit Unsigned Integer to HEX Failing

I have a C++ Vector full of uint8_t values from a TCP data segment. I am looking specifically for 1 of two values which should be at the first index of the vector.

I have the following if statement to express my logic. 

if ( ui8BufferIn.at(0) != 0xE4 || ui8BufferIn.at(0) != 0xE2){
    printf("\nWe have a problem, no parsing will be done, Package Type = %u\n", ui8BufferIn.at(0));
    proceed = false;
}

The above if statement is executing when it shouldn't. I get the following printout: 

We have a problem, no parsing will be done, Package Type = 226

So you don't have to do the math, 226 as an integer is 0xE2 in HEX.

I've been at this a while, so it very well may be something simple, but any help would be great!

Solution

  • I think you might want your logic to be:

    if ( ui8BufferIn.at(0) != 0xE4 && ui8BufferIn.at(0) != 0xE2){

    As right now you're saying "If either case of: (it's not 0xE4) or case of: (it's not 0xE2), we have a problem" - which, if I understand correctly, is not what you want to say. With your statement, you could be getting 0xE2, but because you're not getting 0xE4 (ui8BufferIn.at(0) != 0xE4), your statement executes.