C Server - Print Received Massage? - c

Question

I send this C Server a message w/ netcat.
echo <message> | nc <ip> <port>
it prints:
Client IP : <ip>
I want it to also print:
Client Message : <message>
C SERVER
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <err.h>
char response[] = "hi";
int main()
{
int one = 1, client_fd;
struct sockaddr_in svr_addr, cli_addr;
socklen_t sin_len = sizeof(cli_addr);
int sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock < 0)
err(1, "can't open socket");
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(int));
int port = 85;
svr_addr.sin_family = AF_INET;
svr_addr.sin_addr.s_addr = INADDR_ANY;
svr_addr.sin_port = htons(port);
if (bind(sock, (struct sockaddr *) &svr_addr, sizeof(svr_addr)) == -1) {
close(sock);
err(1, "Can't bind");
}
listen(sock, 5);
while (1) {
client_fd = accept(sock, (struct sockaddr *) &cli_addr, &sin_len);
printf("Client IP : [%s]\n", inet_ntoa(cli_addr.sin_addr));
if (client_fd == -1) {
perror("Can't accept");
continue;
}
write(client_fd, response, sizeof(response) - 1); /*-1:'\0'*/
close(client_fd);
}
}

Answer 1

You just have to read data from the socket (after the accept call, once you've checked that client_fd is usable):
if (client_fd == -1) {
perror("Can't accept");
continue;
}
printf("Client Message : <");
/* buffer to store result */
char buffer[64] = "";
/* while we can read from socket */
while (read(client_fd, buffer, sizeof buffer-1) > 0)
{
/* write what have been read */
printf("%s", buffer);
}
puts(">");
write(client_fd, response, sizeof(response) - 1); /*-1:'\0'*/
close(client_fd);
You could also use recv function.