How do I declare several variables in a for (;;) loop in C?

Question

I thought one could declare several variables in a for loop:

for (int i = 0, char* ptr = bam; i < 10; i++) { ... }

But I just

Answer 1

It's true that you can't simultaneously declare and initialize declarators of different types. But this isn't specific to for loops. You'll get an error if you do:

int i = 0, char *ptr = bam;

too. The first clause of a for loop can be (C99 §6.8.5.3) "a declaration" or a "void expression". Note that you can do:

int i = 0, *j = NULL;
for(int i = 0, *j = NULL;;){}

because i and *j are both of type int. The exact syntax for a declaration is given in §6.7