lvalue required as increment operand using pointers and struct

Question

May I know whats wrong?

for ( ; *line[0]; ++line[0], ++p->title) p->title = tolower(*line[0]);

p is a struct and title is a char pointer, line is a string/char pointer

typedef struct p{
    char *title;
} p;

I'm trying to convert the string to all lower case.

Answer 1

You are using p as a pointer to a struct. If you need title you should use the period operator like this:

p.title