How to determine the length of an array of strings in C

Question

I have a function which splits a string into tokens and stores it in an array. How to determine the size of an array of strings of type char**?

ie: char **input;

Given only the pointer-to-pointer, you must have some termination rule (a finishing known-value, such as NULL). There is no standard way to "know" a sequence length given only a base pointer to it. Ever wonder why so many functions taking sequence pointers are also provide a size_t length ? Now you know. — WhozCraig
– WhozCraig, Commented Apr 17, 2017 at 4:11
The short answer is also keep a counter of each token. If you are doing this in function, you can pass a pointer to size_t and update the value with the count so that it is available back in the calling function while still allowing you to return a pointer-to-pointer-to-char. Keeping a counter also allows you to validate you do not assign more strings than you have allocated pointers. — David C. Rankin
– David C. Rankin, Commented Apr 17, 2017 at 4:32
@technosaurus: Actually argv is NULL-terminated; ther is no immanent need for argc ;-) — too honest for this site
– too honest for this site, Commented Apr 17, 2017 at 5:43

sreepurna · Accepted Answer · 2017-04-17 04:52:32Z

2

Keep a variable globally and increment that variable value in the function which is splitting the string into tokens & storing into array.

answered Apr 17, 2017 at 4:52

sreepurna

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