server.c

#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <netinet/in.h>

#define BUFFER_SIZE 1024
#define NAME_SIZE 2048

int handling(int c)  {
    char buffer[BUFFER_SIZE], name[NAME_SIZE];
    int bytes;

    strcpy(buffer, "My name is: ");

    bytes = send(c, buffer, strlen(buffer), 0);

    if (bytes == -1) return -1;

    bytes = recv(c, name, sizeof(name), 0);

    if (bytes == -1) return -1;

    name[bytes - 1] = '\0';

    sprintf(buffer, "Hello %s, nice to meet you!\r\n", name);

    bytes = send(c, buffer, strlen(buffer), 0);

    if (bytes == -1) return -1; return 0;
}

int main(int argc, char *argv[])  {
    int s, c, cli_size;
    struct sockaddr_in srv, cli;

    if (argc != 2) {
        fprintf(stderr, "usage: %s port\n", argv[0]);
        return 1;
    }

    s = socket(AF_INET, SOCK_STREAM, 0);

    if (s == -1) {
        perror("socket() failed");
        return 2;
    }

    srv.sin_addr.s_addr = INADDR_ANY;
    srv.sin_port = htons( (unsigned short int) atol(argv[1]));
    srv.sin_family = AF_INET;

    if (bind(s, &srv, sizeof(srv)) == -1) {
        perror("bind() failed");
        return 3;
    }

    if (listen(s, 30) == -1) {
        perror("listen() failed");
        return 4;
    }

    for(;;) {

        //c = accept(s, (struct sockaddr *) &cli, sizeof(cli));
        c = accept(s, NULL, NULL);

        if (c == -1) {
            perror("accept() failed");
            return 5;
        }

        printf("client from %s", inet_ntoa(cli.sin_addr));

        if (handling(c) == -1) fprintf(stderr, "%s: handling() failed", argv[0]);

        close(c);
    }

    return 0;
}