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/*
 * Internet Socket Example
 * -----------------------
 *   Here is an example showing how to create and name a socket in the
 * Internet namespace.  The newly created socket exists on the machine that
 * the program is running on.  Rather than finding and using the machine's
 * Internet address, this example specifies `INADDR_ANY' as the host
 * address; the system replaces that with the machine's actual address.
 */

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

int make_socket (unsigned short int port)
{
    int sock;
    struct sockaddr_in name;

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

    /* Give the socket a name. */
    name.sin_family = AF_INET;
    name.sin_port = htons (port);
    name.sin_addr.s_addr = htonl (INADDR_ANY);
    if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0) {
	perror ("bind");
	exit (EXIT_FAILURE);
    }

    return sock;
}


/*
 * Here is another example, showing how you can fill in a `sockaddr_in'
 * structure, given a host name string and a port number:
 */

void init_sockaddr (struct sockaddr_in *name, const char *hostname,
	unsigned short int port)
{
    struct hostent *hostinfo;

    name->sin_family = AF_INET;
    name->sin_port = htons (port);
    hostinfo = gethostbyname (hostname);
    if (hostinfo == NULL) {
	fprintf (stderr, "Unknown host %s.\n", hostname);
	exit (EXIT_FAILURE);
    }
    name->sin_addr = *(struct in_addr *) hostinfo->h_addr;
}

.

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