Let's assume we have one big string consisting of 2 smaller strings that will be seperated an a few iterators to the whole string. I'm a bit confused what will happen to my iterators when I modify the string as followed:

full_string = A1|B2
The two strings a represented by A and B, 1 and 2 are iterators.

Another iterator will go through the string, character per character, and once it reaches 2 the mess begins: 1 is replaced with "hello" while the position of 2 still has to be kept.

I'm not sure how I can assure that the position of 2 is kept correctly when the string is expanded at 1; assuming the iterator at 2 would point at the 5th element of the string (A1|B2<--) it won't point to the right character after the modification (Ahell<--o|B2).

So how can I assure that the position of 2 is kept although I'm modifying the string?

If iterator is not the thing to use here feel free to suggest something else. I just wouldn't want a pointer as it would quite obviously point to an adress which would be even trickier to correct as the string doesn't need to be kept in one place of the memory but could scatter trough the memory (it's a pretty large string).

What's the purpose of this piece of code? Would it not be a better idea to iterate through your long string, extract pieces of it into other smaller strings which you can then modify and recombine?

I want to mark certain positions in the string and modify it later at these exact positions. The question is simply how I can work on one position, expand and thereby increasing the stringlength, while still keeping the other positions? If I simply cut the string into two pices and then join them after modifications my iterators still won't point at the right place. Again, if I modify them and insert the first substring into the large string I will lose all the other positions. So the question is how to keep these nice iterators in place or at least how to correct them.

I was thinking an iterator is something like a counter, so it would point at position 7. If I insert something into the string that is 5 chars long the 7th position won't be what I want anymore. However, if I add 5 to the 7 I should end up where I wanted to be. At least that's what I'm thinking right now but I have no clue if this is just the least bit correct.

take a look at the strtok() function.

Ibbo