>> thanks, maybe i am being a bit slow here

No, sorry. It's my fault. I should have been more clear.


>> i have 3 values in one string, each value separated by a token (comma in this case)

First some terminology : the comma is the separator in this case ... what is between the separators are the tokens.


>> any chance you can show me an example of working code?

It would be very easy for me, but I prefer to help you find the code yourself by giving you hints and nudges in the good direction. I found that the best way to learn something ... if you don't mind ;)


So, I'll be a bit more verbose this time :

Let's first see what the piece of code I posted does :

        char str[] = "hello,1234567,0s0d";
        char *tok = strtok(str, ",");
       
        while (tok) {
         
          strtok(0, ",");
        }

strtok modifies the original string, so you always have to make sure that it is writable (and that it can be modified). The first strtok (the one outside of the while) will find the first separator (in this case we chose the comma) in the str string. It will replace that separator by a null character '\0'. So before str consisted of these characters :

        'h'  'e'  'l'  'l'  'o'  ','  '1'  '2'  '3'  '4'  '5'  '6'  '7'  ','  '0'  's'  '0'  'd'  '\0'

and after :

        'h'  'e'  'l'  'l'  'o'  '\0'  '1'  '2'  '3'  '4'  '5'  '6'  '7'  ','  '0'  's'  '0'  'd'  '\0'

strtok will return a pointer to the first character of the token that was found (in this case the 'h' of "hello"), and will keep a pointer to the rest of the string internally (in this case the '1' just after the '\0'). This internal pointer is necessary so that the next call of strtok knows where to start.

So, then the while loop is started, and we can do something with the found token "hello". After that, we look for the next token with a new strtok call. This time however, we pass NULL as the first parameter to signify that we want to continue with the previous string (and so that we want to use the internal stored pointer). Again strtok will find the next separator, starting from the '1' character, and will replace it with '\0', so we get :

        'h'  'e'  'l'  'l'  'o'  '\0'  '1'  '2'  '3'  '4'  '5'  '6'  '7'  '\0'  '0'  's'  '0'  'd'  '\0'

and find the token "1234567". And the final strtok call will not find any separator any more, and will thus return the final token "0s0d".


Now ... this was just for your information so you understand better what happens, and how strtok works. If something isn't clear - feel free to ask.


How can we make use of this now ? There are two main approaches :

1) you can keep the while loop as I showed it, and store the tokens in an array of strings. With each iteration of the while loop, you increment the index into that array, so the next token will be stored at the next position.

2) you can also store the tokens in separate variables (not an array). In that case, it's best to get rid of the while loop, and just call strtok 3 times in a row - ie. unroll the while loop.

Which approach you choose, depends on the requirements. From your last post, I understand that you want to take the second approach ? If so, then just take leave out the while loop, and call strtok 3 times. After each call to strtok, you can store the found token in one of the variables.

Does that get you going ? If so, give it a try, and post what you get here. If not, feel free to ask for clarification where needed.