How does strchr implementation work

Question

I tried to write my own implementation of the strchr() method.

It now looks like this:

char *mystrchr(const char *s, int c) {
    while (*s != (char)         


        

Answer 1

The const keyword means that the parameter cannot be modified.

You couldn't return s directly because s is declared as const char *s and the return type of the function is char *. If the compiler allowed you to do that, it would be possible to override the const restriction.

Adding a explicit cast to char* tells the compiler that you know what you're doing (though as Eric explained, it would be better if you didn't do it).

UPDATE: For the sake of context I'm quoting Eric's answer, since he seems to have deleted it:

You should not be modifying s since it is a const char *.

Instead, define a local variable that represents the result of type char * and use that in place of s in the method body.