sscanf

kornerr · 09-15-2006, 11:27 PM

I have:

Code:

 const int BS = 128;
    // cmp stands for char tmp
    char buf[BS],
         cmp[BS];
    - - - -
    sscanf (buf, "VIDEO_DRIVER=%s", &cmp);

When compiling I get warning:

Quote:

src/settings.cpp:204: warning: char format, different type arg (arg 3)

What am I doing wrong? (App works ok)
Thanks.

KenJackson · 09-15-2006, 11:40 PM

I think you want to get rid of that ampersand.

Code:

sscanf (buf, "VIDEO_DRIVER=%s", cmp);

jlliagre · 09-15-2006, 11:41 PM

That should be

Code:

sscanf (buf, "VIDEO_DRIVER=%s", &cmp[0]);

, or simply

Code:

sscanf (buf, "VIDEO_DRIVER=%s", cmp);

kornerr · 09-16-2006, 12:37 AM

Thanks, KenJackson, jlliagre.

randyding · 09-16-2006, 09:00 AM

The gcc option -Wformat=0 can disable that warning. With -Wformat on gcc tests the syntax of printf and scanf.
If char cmp[256] is defined then the compiler treats "cmp" and "&cmp" the same. Try...

Code:

int main() {
    char buf[256];
    printf("%p = %p = %p\n", buf, &buf, &buf[0]);
    return 0;
}

PS: actually taking &buf in this example in my opinion is incorrect and confusing... though its allowed anyway by the compiler. I'd have to check if this is ANSI or not.