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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <iostream>
void nonblock(int sockfd)
{
int opts;
opts = fcntl(sockfd, F_GETFL);
if(opts < 0)
{
fprintf(stderr, "fcntl(F_GETFL) failed\n");
}
opts = (opts | O_NONBLOCK);
if(fcntl(sockfd, F_SETFL, opts) < 0)
{
fprintf(stderr, "fcntl(F_SETFL) failed\n");
}
}
int main(int argc, char *argv[])
{
int BUFLEN = 2000;
int sockfd, newsockfd, portno;
socklen_t clilen;
char buffer[BUFLEN];
struct sockaddr_in serv_addr, cli_addr;
int n, i;
int one = 1;
if (argc < 2) {
fprintf(stderr,"please specify a port number\n");
//exit(1);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0) {
perror("ERROR create socket");
exit(1);
}
setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one); //allow reuse of port
//bind to a local address
bzero((char *) &serv_addr, sizeof(serv_addr));
portno = 35; //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) {
perror("ERROR on bind");
exit(1);
}
//listen marks the socket as passive socket listening to incoming connections,
//it allows max 5 backlog connections: backlog connections are pending in queue
//if pending connections are more than 5, later request may be ignored
listen(sockfd,5);
//accept incoming connections
clilen = sizeof(cli_addr);
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
//nonblock(newsockfd); //if we want to set the socket as nonblock, we can uncomment this
if (newsockfd < 0) {
perror("ERROR on accept");
exit(1);
}
printf("connection accepted\n");
cout << "Problém s pojmenováním soketu.");
cin >> NULL;
sleep(2);
close(newsockfd);
close(sockfd);
return 0;
}
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