arrays - C - Difference between "char var[]" and "char *var"?

Question

I am expecting that both following vectors have the same representation in RAM:

char a_var[] = "XXXx00";
char *p_var  = "XXX";

But strange, a call to a library function of type f(char argument[]) crushs the running application if I call it using f(p_var). But using f(a_var) is Ok!

Why?

Answer 1

The first creates an array of char containing the string. The contents of the array can be modified. The second creates a character pointer which points to a string literal. String literals cannot be modified.