Why can't I change a string by index when it is declared by pointer notation?

Question

for example:

char stringer[]="hello";
stringer[2]='A';

The above works to change 'l' to 'A'. But if I do the following:

char *stringer="hello";
stringer[2]='A';

This doesn't work, is there a reason for this?

Answer 1

As answered by Some programmer dude in comments:

Literal strings are really non-modifiable arrays of characters. With char *stringer="hello"; you make stringer point to the first character of such an array. Attempting to modify its contents leads to undefined behavior.

That's why you should always use const char * when pointing to literal strings.

Strings can be modified when using pointer, if the pointer is pointing to something you're allowed to modify. For example

char stringer[] = "hello"; 
char *pointer = stringer; 
pointer[2] = 'A';