const char *x; char const *a = x; char *b; char *c = "ABCDEF"; b = (char*)malloc(sizeof(char)*120); memcpy(b, "Anything", 9); // Illegal memcpy(c, b, 5); // c points to a "constant" memory area // Legal x = b; // x (the pointer) can be modified // Illegal memcpy(x, "1234", 5); // Although the memory is not constant, x is a pointer to constant memory, so this should not be allowed // Illegal a = x; // a cannot point to any other place (a cannot be modified) // Legal free(b); b = strdup(c); // Now you can use a COPY of the data that is constant in a non-constant memory area// and so on...