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;
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Answer 1

other simpler way to memorize

Case -1 :

step-1 : char *p;

step -2 : please read it like below

char (*p); ==> p is a pointer to a char

now you just need to do malloc for the type (step-2) without braces

i.e., p = malloc(sizeof(char) * some_len);

Case -2 :

step-1 : char **p;

step -2 :

please read it like below

char* (* p); ==> p is a pointer to a char *

now you just need to do malloc for the type (step-2) without braces

i.e., p = malloc(sizeof(char *) * some_len);

Case -3 :

No one uses this but just for sake of explanation

char ***p;

read it as,

char** (*p); ==> p is a pointer to a char** (and for this check case-2 above)

p = malloc(sizeof(char**) * some_len);