client.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

int main(int argc, char** argv)
{
  int sd;
  struct sockaddr_in addr;
  struct sockaddr_in c_addr;

  if((sd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
    perror("socket");
    return EXIT_SUCCESS;
  }

  c_addr.sin_family = AF_INET;
  c_addr.sin_port = htons(33400);
  c_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
  if (bind(sd, (struct sockaddr*)&c_addr, sizeof(c_addr))) {
    perror("client bind");
    return EXIT_FAILURE;
  }

  addr.sin_family = AF_INET;
  addr.sin_port = htons(22222);
  addr.sin_addr.s_addr = inet_addr("127.0.0.1");

  connect(sd, (struct sockaddr *)&addr, sizeof(struct sockaddr_in));

  if(send(sd, "I am send process", 17, 0) < 0) {
    perror("send");
    return EXIT_FAILURE;
  }

  close(sd);

  return EXIT_SUCCESS;
}