compare unity8_t to a string not working

[Canedje]

I do try to test an unity8_t var (payload) with a string (p).

I do convert a string to an unity8_t var called p, by:

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String test = "message received : Ben je er al?";
const uint8_t* p = reinterpret_cast<const uint8_t*>(test.c_str());

Then I do compare "p" with a websocket called "payload" by:

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if ( payload == p) {

If I print both p and payload I do see no difference but the if test is false?

How is this possible?
What am I doing wrong?

[PeterO]

Do you understand what a pointer is ?

PeterO

[Canedje]

yes I do.
In the past I did programming. That is a while ago.

[PeterO]

yes I do..

Are you sure ? You are comparing pointers to two strings and wondering why they aren't the same. You need to compare the strings themselves, not their addresses.

PeterO

[Canedje]

Thanks.
I know that a pointer is an adress to the value and not the value itself.
I still having trouble comparing a uint8_t with a string.

I do try to compare the uint8_t var named "payload" with a string named "test"
If both the value is : "Ben je er al?" the if statement is true.
I don't know how the codse looks like to change uint8_t pointer the string itself string
How to make the code to compare these in a if test.

[topguy]

http://www.cplusplus.com/reference/cstring/strcmp/

[Canedje]

Thanks again.
This was what I needed.