source: trunk/instant_messenger/socket/BKP_20071105/BKP_20071026/BKP_20071019/BKP_20071018/BKP_20071009/BKP_20071008/BKP/BKP/keepalive.c @ 151

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

int main(void);

int main()
{
        int s;
        int optval;
        socklen_t optlen = sizeof(optval);

        /* Create the socket */
        if((s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
                perror("socket()");
                exit(EXIT_FAILURE);
        }

        /* Check the status for the keepalive option */
        if(getsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &optval, &optlen) < 0) {
                perror("getsockopt()");
                close(s);
                exit(EXIT_FAILURE);
        }
        printf("SO_KEEPALIVE is %s\n", (optval ? "ON" : "OFF"));

        /* Set the option active */
        optval = 1;
        optlen = sizeof(optval);
        if(setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &optval, optlen) < 0) {
                perror("setsockopt()");
                close(s);
                exit(EXIT_FAILURE);
        }
        printf("SO_KEEPALIVE set on socket\n");

        /* Check the status again */
        if(getsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &optval, &optlen) < 0) {
                perror("getsockopt()");
                close(s);
                exit(EXIT_FAILURE);
        }
        printf("SO_KEEPALIVE is %s\n", (optval ? "ON" : "OFF"));

        close(s);

        exit(EXIT_SUCCESS);
}