#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#include <stdio.h>
#include <string.h>

#include <sys/signal.h>

#define PROTOPORT       5050            /* default protocol port number */
#define QLEN            6               /* size of request queue        */

main(argc, argv)
int     argc;
char    *argv[];
{
        struct  hostent  *ptrh;  /* pointer to a host table entry       */
        struct  protoent *ptrp;  /* pointer to a protocol table entry   */
        struct  sockaddr_in sad; /* structure to hold server's address  */
        struct  sockaddr_in cad; /* structure to hold client's address  */
        int     sd, sd2;         /* socket descriptors                  */
        int     port;            /* protocol port number                */
        int     alen;            /* length of address                   */

        memset((char *)&sad,0,sizeof(sad)); /* clear sockaddr structure */
        sad.sin_family = AF_INET;         /* set family to Internet     */
        sad.sin_addr.s_addr = INADDR_ANY; /* set the local IP address   */
	sad.sin_port = htons((u_short)PROTOPORT);

        if ( ((int)(ptrp = getprotobyname("tcp"))) == 0) {
                fprintf(stderr, "cannot map \"tcp\" to protocol number");
                exit(1);
        }

        /* Create a socket */

        sd = socket(PF_INET, SOCK_STREAM, ptrp->p_proto);
        if (sd < 0) {
                fprintf(stderr, "socket creation failed\n");
                exit(1);
        }

        /* Bind a local address to the socket */

        if (bind(sd, (struct sockaddr *)&sad, sizeof(sad)) < 0) {
                fprintf(stderr,"bind failed\n");
                exit(1);
        }

        /* Specify size of request queue */

        if (listen(sd, QLEN) < 0) {
                fprintf(stderr,"listen failed\n");
                exit(1);
        }

	signal(SIGCHLD, SIG_IGN) ;

        /* Main server loop - accept and handle requests */

        while (1) {
                alen = sizeof(cad);
                if ( (sd2=accept(sd, (struct sockaddr *)&cad, &alen)) < 0) {
                        fprintf(stderr, "accept failed\n");
                        exit(1);
                }
		if (fork()) {
		  /* I am the parent! */
		  close(sd2) ;
		} else {
		  /* I am the child! */
		  close(sd) ;
		  dup2(sd2, 0) ;
		  dup2(sd2, 1) ;
		  close(sd2) ;
		  execl("/usr/users/brock/classes/363/f99/examples/echoline",
			"echoline",
			NULL) ;
		  printf(stderr, "Should never get here\n") ;

		}
        }
}