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#include <err.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <poll.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netdb.h>
int main()
{
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = 0;
hints.ai_protocol = 0;
struct addrinfo *result;
int ret = getaddrinfo("127.0.0.1", "24242", &hints, &result);
if (ret == -1) {
err(EXIT_FAILURE, "failed getting addr info");
}
int tcp_sock = -1;
for (struct addrinfo *rp = result; rp != NULL; rp = rp->ai_next) {
int s = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
if (s == -1)
continue;
if (connect(s, rp->ai_addr, rp->ai_addrlen) != -1) {
tcp_sock = s;
break;
}
close(s);
}
freeaddrinfo(result);
if (tcp_sock == -1) {
err(EXIT_FAILURE, "couldn't connect to socket");
return -1;
}
ret = fcntl(tcp_sock, F_SETFL, O_NONBLOCK);
if (ret == -1) {
close(tcp_sock);
return ret;
}
struct pollfd polls[2] = {{
.fd = STDIN_FILENO,
.events = POLLIN
}, {
.fd = tcp_sock,
.events = POLLIN
}
};
while (poll(polls, 2, -1)) {
if (polls[0].revents) {
char cb = 'a';
int ret = read(STDIN_FILENO, &cb, 1);
if (ret == -1) {
err(EXIT_FAILURE, "failed reading from stdio");
}
if (ret == 0) {
break;
}
ret = write(tcp_sock, &cb, 1);
if (ret == -1) {
err(EXIT_FAILURE, "failed writing to socket");
}
}
if (polls[1].revents) {
if (polls[1].revents & POLLHUP) {
printf("Closed socket\n");
break;
}
char buf[4096];
int ret = read(tcp_sock, buf, 4096 - 1);
if (ret == -1 && errno != EWOULDBLOCK) {
err(EXIT_FAILURE, "failed reading from socket");
}
if (ret == 0) {
printf("Closed socket\n");
break;
}
buf[ret] = '\0';
printf("%s\n", buf);
}
}
close(tcp_sock);
}
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