fscanf error

knobby67 · 09-23-2007, 01:29 PM

hello, I hope someone can help me out as I'm a bit puzzeled by this warning, the warning is

warning: char format, different type arg (arg 3)

I get this from the following code

static int aseGetGEOMOBJECT(FILE *s)
{
char data[255];
int count=0;

rewind (s);
while (!feof (s))
{
fscanf(s, "%s", &data); THIS IS ERROR
if (!strcmp (data,"*GEOMOBJECT")) count++;
}

printf("number of objects %d\n",count);

return(count);

}

Thanks

jdiggitydogg · 09-23-2007, 03:16 PM

as you probably know, fscanf wants a character pointer for arg3, but you are passing it a pointer to a character pointer...so the compiler throws a warning.

just use 'data' and omit the '&'. in C, an array name by itself is an address (i.e. pointer) to the first element of the array. so in essense, '&data' is the address of the pointer. instead, you just want the pointer of itself. alternatively, you could do '&data[0]'.

bigearsbilly · 09-25-2007, 07:10 AM

you are generally better off, IMHO,
for non-trivial programs, in reading the input as one string (fgets maybe)
and parsing it at leisure.
messing about with scanf is a pain.