#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int
main(int argc, char *argv[])
{
        int i;

        if (argc < 2)
                exit(1);

        for (i = 1; i < argc; ++i) {
                char *endptr;
                int fd;

                fd = strtol(argv[i], &endptr, 10);
                if (*endptr != '\0')
                        exit(1);

                if (close(fd) < 0) {
                        int error = errno;

                        if (error != EBADF) {
                                warnx("close error %d", error);
                                exit(2);
                        }
                } else {
                        warnx("%d is still valid", fd);
                        exit(2);
                }
        }
        exit(0);
}