Assigning memory to double pointer?

Question

I am having trouble understanding how to assign memory to a double pointer. I want to read an array of strings and store it.

    char **ptr;
    fp = fopen(\         


        

Answer 1

A double pointer is just a pointer to another pointer. So you can allocate it like this:

char *realptr=(char*)malloc(1234);
char **ptr=&realptr;

You have to keep in mind where your pointer is stored at (in this example the double pointer points to a pointer variable on the stack so it's invalid after the function returns).