/* A simple server in the internet domain using TCP
The port number is passed as an argument */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
void error(const char *msg)
{
perror(msg);
exit(1);
}
int main(int argc, char *argv[])
{
int sockfd, newsockfd, portno;
socklen_t clilen;
struct sockaddr_in serv_addr, cli_addr;
int n;
ssize_t recv;
struct msghdr mh;
struct iovec iov[1];
char primo[256];
memset(&mh, 0, sizeof(mh));
memset(iov, 0, sizeof(iov));
/* Specify the components of the message in an "iovec".*/
iov[0] .iov_base = (caddr_t)primo;
iov[0] .iov_len = sizeof(primo);
/*set iov in mh*/
mh.msg_iov = iov;
mh.msg_iovlen = sizeof(iov);
printf("Structures initialized \n");
if (argc < 2) {
fprintf(stderr,"ERROR, no port provided\n");
exit(1);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
error("ERROR opening socket");
bzero((char *) &serv_addr, sizeof(serv_addr));
portno = atoi(argv[1]);
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(portno);
if (bind(sockfd, (struct sockaddr *) &serv_addr,
sizeof(serv_addr)) < 0)
error("ERROR on binding");
listen(sockfd,500);
clilen = sizeof(cli_addr);
newsockfd = accept(sockfd,
(struct sockaddr *) &cli_addr,
&clilen);
if (newsockfd < 0)
error("ERROR on accept");
printf("Waiting on recvmsg() \n");
recv = recvmsg(sockfd, &mh, 0);
if (recv == -1) {
perror("recvmsg failed ");
strerror(errno);
return -1;
}
n = write(newsockfd,"I got your message",18);
if (n < 0) error("ERROR writing to socket");
close(newsockfd);
close(sockfd);
return 0;
}