Hello,

I have never seen the use of

['N'] = "NORTH",
['S'] = "SOUTH",
['E'] = "EAST",
['W'] = "WEST",

before. I didnt even know that this is possible :D. Could you explain what this is and what the benefit of the use is? (I assume it is faster, less code in the if-routine and I can use keywords?)

Thanks in advance.

Because the strtok will replace the delimiter as '\0', but input argument ip is const.

overkill

ugh okay, thx

You do not free sdup, therefore leak memory.

res is overwritten by asprintf, so we need to save previous value of res to free memory.

You never free str, therefore, leak memory.

In case of sz <= 0 || l == 0 || sz > l you return static string which cannot be freed. In other cases you return allocated string. This requires from caller additional checks whether to free the returned string or not, so it is not very convenient.

In case of strlen(s) < sz || sz <= 0 you return static string which cannot be freed. In other cases you return allocated string. This requires from caller additional checks whether to free the returned string or not, so it is not very convenient.

Initial value of *lg == -1 is not documented.

Several issues:

1. return *lg = 0; -- return value is wrong.
2. char **ret = malloc(sz * sizeof(char**)); -- not correct. Correct is char **ret = malloc(sz * sizeof(char*));
3. If all strings in arr are freed after dirReduc call, the result will become invalid.

When you call pop, you should free the string you pop. Otherwise you get memory leak.

What if someone free strings in the input array right after dirReduc call? The result will become invalid and if you will try to read the result, you will get undefined behavior. This cannot be "Best Practice" solution.

Why do we need strdup here?