How to detect if user inserts data with commas (in a desired format) or not?

Question

User inserts data in a format:\" [NAME], [SURNAME], [INDEX] \". Errors codes:
0 -- everything is loaded to the structure properly
1 -- not loaded to structure pr

Answer 1

I would use this pseudo-code:

isolate first comma-separated token
if no token, return 1
if length >= sizeof(s.name), return 1
copy first token to s.name
isolate second token
if no token, return 2
if length >= sizeof(s.surname), return 2
copy first token to s.surname
isolate third token
if no token, return 3
if token not numeric, return 3
set s.index = atoi( third token )
return 0

If you code that up in C, you should end up with something nice and short and clean and reliable, without too many annoyingly redundant checking and backtracking.

(Actually, if it was me, I'd use one general-purpose function to do the token isolating all at once, up front, then simply test if the number of found tokens was 0, 1, 2, 3, or more than 3. See this web page for additional ideas.)