#include <errno.h>
#include <stdio.h>
#include <sys/select.h>

volatile unsigned int variable = 0;

int main()
{
    struct timeval tv;
    int val;

    for (;;)
    {
        tv.tv_sec = 1;
        tv.tv_usec = 0;

        do
        {
            val = select(0, NULL, NULL, NULL, &tv);
        } while (val != 0 && errno == EINTR);

        printf("Variable = %u\n", ++variable);
    }
}