char pointer initialization in C

Question

I am not so clear on character pointer and how they work.

The program builds, but crashes when I run it.

 char *ab = NULL;
 //ab = \"abc123\"; // works f         


        

Answer 1

You need to allocate memory for your data. Indeed sprintf takes char*, but it doesn't allocate memory for you.

The first line works fine because compiler automatically allocates data for constant tables of chars defined at compile time.