Thread: Getting System(); Command to Return Value

I'm using int x; to return the value (0 or 1) from system(cmd); command. However, it always returns 0. Any idea's? Here's the code:

Code:

#include <iostream>

using namespace std;

int main(void)
{
    char cmd[100];
    int ip_a, ip_b, ip_c, ip_d, i, x;
    
    printf("IP Address: ");
    scanf("%d.%d.%d.%d", &ip_a, &ip_b, &ip_c, &ip_d);
    
    if (ip_a < 0 || ip_a > 255) return 0;
    if (ip_b < 0 || ip_b > 255) return 0;
    if (ip_c < 0 || ip_c > 255) return 0;
    if (ip_d < 0 || ip_d > 255) return 0;
    
    for ( i = 0; i < 4; i++ ) {
        sprintf(cmd, "ping %d.%d.%d.%d -n 1 > nul", ip_a, ip_b, ip_c, ip_d);
        x = system(cmd);
        printf("X-Value = %d\n", x);
    }
    
    system("pause > nul");
    return 0;
}

When you say "error," do you mean if the IP address doesn't exist, or if something is done incorrectly?

By error I mean something went wrong, whether it was that system couldn't open your command interpreter or some other reason....the way to tell what went wrong is to check errno (read through the link i posted it explains it pretty well)

> However, it always returns 0. Any idea's?
Whether system() returns anything useful is system dependent.
DOS/Win32 is famously broken for always returning zero.

Most unix systems successfully return the exit status of the program you ran.

Right now, I'm on a school computer, and it uses Microsoft Windows 2000. The one at my house uses Microsoft Windows XP.

Anyways, is there another way of getting the return value (maybe a different method) that isn't broken on Windows-based systems?

Maybe one of the other methods listed in the FAQ?
Running programs within programs springs to mind.