#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/types.h>
#include <machine/cpufunc.h>

void
usage(char *name) {
    fprintf(stderr,
	    "Bad usage\n"
	    "\t%s adr [data]\n"
	    "\n"
	    "Read/write adr with data\n", name);
    exit(1);
}

int
main(int argc, char **argv) {
    int	fd, adr, data;
    
    if (argc != 2 && argc != 3)
	usage(argv[0]);

    if ((fd = open("/dev/io", O_RDWR)) == -1) {
	fprintf(stderr, "Can't open /dev/io: %s\n", strerror(errno));
	exit(1);
    }

    adr = strtol(argv[1], NULL, 0) & 0xffff;

    if (argc == 3) {
	data = strtol(argv[2], NULL, 0) & 0xff;
	printf("0x%02x <- 0x%02x\n", adr, data);
	outb(adr, data);
    } else
	printf("0x%02x -> 0x%02x\n", adr, inb(adr));
	
    exit(0);
}