On 19/10/2016 20:45, fedor_qd wrote:
> How precise [is] this function?
> I write sample:
>
> int main()
> {
> float x, y;
> __builtin_sscanf("30,981", "%f", &x);
> __builtin_printf("Test comma: %f\n", x);
> return(0);
> }
>
> Compile with options: g++ main.c -o hello -static-libgcc
>
> This sample returns 30.00 but 30.981 expected
You passed "30,981" to scanf.
Are you sure ',' is a valid decimal mark in the current locale?
( https://en.wikipedia.org/wiki/Decimal_mark )
If not, the input is equivalent to "30&981", thus scanf will stop
parsing on the unexpected character.
#include <stdio.h>
int main(void)
{
float x, y;
sscanf("30,981", "%f", &x);
sscanf("30.981", "%f", &y);
printf("x=%f y=%f\n", x, y);
return 0;
}
$ ./a.out
x=30.000000 y=30.981001
Regards.
