�ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽv�ｿｽ�ｿｽ�ｿｽO�ｿｽ�ｿｽ�ｿｽ~�ｿｽ�ｿｽ�ｿｽO

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1. �ｿｽ�ｿｽ`

�ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽF Socket�ｿｽBTCP/IP �ｿｽA�ｿｽv�ｿｽ�ｿｽ�ｿｽP�ｿｽ[�ｿｽV�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�成�ｿｽ�ｿｽ�ｿｽ驍ｽ�ｿｽﾟの抵ｿｽ�ｿｽﾛ会ｿｽ�ｿｽ�ｿｽ�ｿｽ黷ｽ�ｿｽC�ｿｽ�ｿｽ�ｿｽ^�ｿｽ[�ｿｽt�ｿｽF�ｿｽ[�ｿｽX�ｿｽB

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2. �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ使�ｿｽp�ｿｽ�ｿｽ

�ｿｽC�ｿｽ�ｿｽ�ｿｽ^�ｿｽ[�ｿｽl�ｿｽb�ｿｽg�ｿｽd�ｿｽb�ｿｽ�ｿｽC�ｿｽ�ｿｽ�ｿｽ^�ｿｽ[�ｿｽl�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾜむゑｿｽ�ｿｽﾗてゑｿｽ TCP/IP �ｿｽA�ｿｽv�ｿｽ�ｿｽ�ｿｽP�ｿｽ[�ｿｽV�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽB

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3. �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾖ撰ｿｽ

�ｿｽﾜゑｿｽ�ｿｽ�ｿｽ sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌに適�ｿｽﾘなパ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^�ｿｽﾝ抵ｿｽ�ｿｽ�ｿｽs�ｿｽ�ｿｽ�ｿｽA�ｿｽﾈ会ｿｽ�ｿｽﾌソ�ｿｽP�ｿｽb�ｿｽg�ｿｽﾖ撰ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽs�ｿｽ�ｿｽ�ｿｽ�ｿｽB
�ｿｽ�ｿｽ�ｿｽ�ｿｽ
socket �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ作成
bind �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾆポ�ｿｽ[�ｿｽg�ｿｽﾌ鯉ｿｽ�ｿｽ�ｿｽ
setsockopt �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽI�ｿｽv�ｿｽV�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾌ設抵ｿｽ
close (Linux), closesocket (Win) �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ終�ｿｽ�ｿｽ
htonl �ｿｽz�ｿｽX�ｿｽg�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽ�ｿｽ�ｿｽl�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ[�ｿｽN�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽﾉ変奇ｿｽ (4�ｿｽo�ｿｽC�ｿｽg)
htons �ｿｽz�ｿｽX�ｿｽg�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽ�ｿｽ�ｿｽl�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ[�ｿｽN�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽﾉ変奇ｿｽ (2�ｿｽo�ｿｽC�ｿｽg)
ntohl �ｿｽl�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ[�ｿｽN�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽ�ｿｽ�ｿｽz�ｿｽX�ｿｽg�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽﾉ変奇ｿｽ (4�ｿｽo�ｿｽC�ｿｽg)
ntohs �ｿｽl�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ[�ｿｽN�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽ�ｿｽ�ｿｽz�ｿｽX�ｿｽg�ｿｽE�ｿｽo�ｿｽC�ｿｽg�ｿｽI�ｿｽ[�ｿｽ_�ｿｽ[�ｿｽﾉ変奇ｿｽ (2�ｿｽo�ｿｽC�ｿｽg)
inet_addr �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽIP�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽﾉ変奇ｿｽ
inet_ntoa IP�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽｶ趣ｿｽ�ｿｽ�ｿｽﾉ変奇ｿｽ
TCP
listen �ｿｽﾚ托ｿｽ�ｿｽL�ｿｽ�ｿｽ�ｿｽ[�ｿｽﾌ作成 (�ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ)
accept �ｿｽﾚ托ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ (�ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ)
connect �ｿｽT�ｿｽ[�ｿｽo�ｿｽﾖの接托ｿｽ (�ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ)
send �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽM
recv �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM
UDP
sendto�ｿｽ@ �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽM
recvfrom �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM

�ｿｽ@

4. �ｿｽﾈ単�ｿｽ�ｿｽTCP/IP�ｿｽv�ｿｽ�ｿｽ�ｿｽO�ｿｽ�ｿｽ�ｿｽ�ｿｽ

�ｿｽﾈ会ｿｽ�ｿｽﾍ、�ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ�ｿｽT�ｿｽ[�ｿｽo�ｿｽﾉ接托ｿｽ�ｿｽ�ｿｽ�ｿｽA1�ｿｽb�ｿｽ�ｿｽ�ｿｽﾆに��ｿｽ�ｿｽb�ｿｽZ�ｿｽ[�ｿｽW�ｿｽ乱M�ｿｽ�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ�ｿｽO�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾅゑｿｽ�ｿｽ�ｿｽ (�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽG�ｿｽ�ｿｽ�ｿｽ[�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾜゑｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽs�ｿｽ�ｿｽ�ｿｽﾄゑｿｽ�ｿｽﾈゑｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ�ｿｽO�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾅゑｿｽ�ｿｽ�ｿｽ)�ｿｽB�ｿｽﾜゑｿｽ�ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽN�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽﾊのマ�ｿｽV�ｿｽ�ｿｽ�ｿｽﾅク�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽN�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽBWindows �ｿｽp�ｿｽ�ｿｽ Linux �ｿｽp�ｿｽﾌプ�ｿｽ�ｿｽ�ｿｽO�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾌ違い�ｿｽﾍほとゑｿｽﾇなゑｿｽ�ｿｽA
�ｿｽC�ｿｽ�ｿｽ�ｿｽN�ｿｽ�ｿｽ�ｿｽ[�ｿｽh�ｿｽ�ｿｽ�ｿｽ�ｿｽw�ｿｽb�ｿｽ_�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ
Windows �ｿｽ�ｿｽ TCP/IP �ｿｽ�ｿｽL�ｿｽ�ｿｽ�ｿｽﾉゑｿｽ�ｿｽ驍ｽ�ｿｽﾟゑｿｽ WSA �ｿｽﾖ撰ｿｽ
�ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽI�ｿｽ�ｿｽ�ｿｽﾌゑｿｽ�ｿｽﾟゑｿｽ closesocket (Windows) �ｿｽ�ｿｽ close (Linux) �ｿｽﾌ違い

�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾈゑｿｽ�ｿｽB�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾎ、�ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ OS �ｿｽﾉ依托ｿｽ�ｿｽ�ｿｽ�ｿｽﾈゑｿｽ�ｿｽﾖ撰ｿｽ�ｿｽQ�ｿｽﾅゑｿｽ�ｿｽ�ｿｽB

�ｿｽ@

Windows�ｿｽﾅ： �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽN�ｿｽI�ｿｽv�ｿｽV�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ ws2_32.lib �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽB

TCP �ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ

 
#include <stdio.h>
#include <winsock2.h>
#include <ws2tcpip.h>

#define BUFFER_SIZE 256

int
main() {
  /* �ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  unsigned short port = 9876;
  int srcSocket;  // �ｿｽ�ｿｽ�ｿｽ�ｿｽ
  int dstSocket;  // �ｿｽ�ｿｽ�ｿｽ�ｿｽ

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in srcAddr;
  struct sockaddr_in dstAddr;
  int dstAddrSize = sizeof(dstAddr);

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int numrcv;
  char buffer[BUFFER_SIZE];

  /************************************************************/
  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSADATA data;
  WSAStartup(MAKEWORD(2,0), &data); 

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&srcAddr, 0, sizeof(srcAddr));
  srcAddr.sin_port = htons(port);
  srcAddr.sin_family = AF_INET;
  srcAddr.sin_addr.s_addr = htonl(INADDR_ANY);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ撰ｿｽ�ｿｽ�ｿｽ */
  srcSocket = socket(AF_INET, SOCK_STREAM, 0);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌバ�ｿｽC�ｿｽ�ｿｽ�ｿｽh */
  bind(srcSocket, (struct sockaddr *) &srcAddr, sizeof(srcAddr));

  /* �ｿｽﾚ托ｿｽ�ｿｽﾌ具ｿｽ�ｿｽ�ｿｽ */
  listen(srcSocket, 1);

  /* �ｿｽﾚ托ｿｽ�ｿｽﾌ趣ｿｽt�ｿｽ�ｿｽ */
  printf("Waiting for connection ...\n");
  dstSocket = accept(srcSocket, (struct sockaddr *) &dstAddr, &dstAddrSize);
  printf("Connected from %s\n", inet_ntoa(dstAddr.sin_addr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM */
  while(1) {
    numrcv = recv(dstSocket, buffer, BUFFER_SIZE, 0); 
    if(numrcv == 0 || numrcv == -1) {
      status = closesocket(dstSocket); break;
    }
    printf("received: %s\n", buffer);
  }

  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSACleanup();
}
�ｿｽ@

TCP �ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ

 
#include <stdio.h>
#include <winsock2.h>
#include <ws2tcpip.h>

int
main() {
  /* IP �ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽA�ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  char destination[80];
  unsigned short port = 9876;
  int dstSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in dstAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int status;
  int numsnt;
  char *toSendText = "This is a test";

  /************************************************************/

  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSADATA data;
  WSAStartup(MAKEWORD(2,0), &data));

  /* �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽﾌ難ｿｽ�ｿｽ�ｿｽ */
  printf("Connect to ? : (name or IP address) ");
  scanf("%s", destination);

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&dstAddr, 0, sizeof(dstAddr));
  dstAddr.sin_port = htons(port);
  dstAddr.sin_family = AF_INET;
  stAddr.sin_addr.s_addr = inet_addr(destination);
 
  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  dstSocket = socket(AF_INET, SOCK_STREAM, 0);

  /* �ｿｽﾚ托ｿｽ */
  printf("Trying to connect to %s: \n", destination);
  connect(dstSocket, (struct sockaddr *) &dstAddr, sizeof(dstAddr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽo */
  for(i=0; i<10; i++) {
    printf("sending...\n");
    send(dstSocket, toSendText, strlen(toSendText)+1, 0);
    Sleep(1000);
  }

  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  closesocket(dstSocket);
  WSACleanup();
}

UDP �ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ

 
#include <stdio.h>
#include <winsock2.h>
#include <ws2tcpip.h>

#define BUFFER_SIZE 256

int
main() {
  /* �ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  int port = 9876;
  int recvSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in recvSockAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int status;
  int numrcv;
  char buffer[BUFFER_SIZE];
  unsigned long on = 1;

  /************************************************************/
  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSADATA data;
  WSAStartup(MAKEWORD(2,0), &data));

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&recvSockAddr, 0, sizeof(recvSockAddr));
  recvSockAddr.sin_port = htons(port);
  recvSockAddr.sin_family = AF_INET;
  recvSockAddr.sin_addr.s_addr = htonl(INADDR_ANY);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  recvSocket = socket(AF_INET, SOCK_DGRAM, 0);
 
  /* �ｿｽo�ｿｽC�ｿｽ�ｿｽ�ｿｽh */
  status = bind(recvSocket, (struct sockaddr_in *) &recvSockAddr, sizeof(recvSockAddr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM */
  while(1) {
    numrcv = recvfrom(recvSocket, buffer, BUFFER_SIZE, 0, NULL, NULL);
    if(numrcv == -1) { status = closesocket(recvSocket); break; }
    printf("received: %s\n", buffer);
  }

  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSACleanup();
}

UDP �ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ

 
#include <stdio.h>
#include <winsock2.h>
#include <ws2tcpip.h>

int
main() {
  /* IP�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽA�ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  char destination[80];
  unsgined short port = 9876;
  int destSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in destSockAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int i;
  char *toSendText = "This is a test";

  /************************************************************/
  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  WSADATA data;
  WSAStartup(MAKEWORD(2,0), &data));

  /* �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽﾌ難ｿｽ�ｿｽ�ｿｽ */
  printf("Connect to ? : (name or IP address) ");
  scanf("%s", destination);

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&destSockAddr, 0, sizeof(destSockAddr));
  destSockAddr.sin_addr.s_addr = inet_addr(destination);
  destSockAddr.sin_port = htons(port);
  destSockAddr.sin_family = AF_INET;

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  destSocket = socket(AF_INET, SOCK_DGRAM, 0);
 
  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽo */
  for(i=0; i<10; i++) {
    printf("sending...\n");
    sendto(destSocket, toSendText, strlen(toSendText)+1, 0, &destSockAddr, sizeof(destSockAddr));
    Sleep(1000);
  }

  /* Windows �ｿｽﾆ趣ｿｽ�ｿｽﾌ設抵ｿｽ */
  closesocket(destSocket);
  WSACleanup();
}

�ｿｽ@

Linux�ｿｽﾅ： �ｿｽR�ｿｽ�ｿｽ�ｿｽp�ｿｽC�ｿｽ�ｿｽ�ｿｽ�ｿｽ "gcc �ｿｽ\�ｿｽ[�ｿｽX�ｿｽ�ｿｽ -lsocket" �ｿｽﾆゑｿｽ�ｿｽ�ｿｽB

TCP �ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ

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

#define BUFFER_SIZE 256

int
main() {
  /* �ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  unsigned short port = 9876;
  int srcSocket;  // �ｿｽ�ｿｽ�ｿｽ�ｿｽ
  int dstSocket;  // �ｿｽ�ｿｽ�ｿｽ�ｿｽ

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in srcAddr;
  struct sockaddr_in dstAddr;
  int dstAddrSize = sizeof(dstAddr);

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int numrcv;
  char buffer[BUFFER_SIZE];

  /************************************************************/
  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&srcAddr, 0, sizeof(srcAddr));
  srcAddr.sin_port = htons(port);
  srcAddr.sin_family = AF_INET;
  srcAddr.sin_addr.s_addr = htonl(INADDR_ANY);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ撰ｿｽ�ｿｽ�ｿｽ */
  srcSocket = socket(AF_INET, SOCK_STREAM, 0);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌバ�ｿｽC�ｿｽ�ｿｽ�ｿｽh */
  bind(srcSocket, (struct sockaddr *) &srcAddr, sizeof(srcAddr));

  /* �ｿｽﾚ托ｿｽ�ｿｽﾌ具ｿｽ�ｿｽ�ｿｽ */
  listen(srcSocket, 1);

  /* �ｿｽﾚ托ｿｽ�ｿｽﾌ趣ｿｽt�ｿｽ�ｿｽ */
  printf("Waiting for connection ...\n");
  dstSocket = accept(srcSocket, (struct sockaddr *) &dstAddr, &dstAddrSize);
  printf("Connected from %s\n", inet_ntoa(dstAddr.sin_addr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM */
  while(1) {
    numrcv = recv(dstSocket, buffer, BUFFER_SIZE, 0); 
    if(numrcv == 0 || numrcv == -1) {
      status = close(dstSocket); break;
    }
    printf("received: %s\n", buffer);
  }
}
�ｿｽ@

TCP �ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ

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

int
main() {
  /* IP �ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽA�ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  char destination[80];
  unsigned short port = 9876;
  int dstSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in dstAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int status;
  int numsnt;
  char *toSendText = "This is a test";

  /************************************************************/
  /* �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽﾌ難ｿｽ�ｿｽ�ｿｽ */
  printf("Connect to ? : (name or IP address) ");
  scanf("%s", destination);

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&dstAddr, 0, sizeof(dstAddr));
  dstAddr.sin_port = htons(port);
  dstAddr.sin_family = AF_INET;
  stAddr.sin_addr.s_addr = inet_addr(destination);
 
  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  dstSocket = socket(AF_INET, SOCK_STREAM, 0);

  /* �ｿｽﾚ托ｿｽ */
  printf("Trying to connect to %s: \n", destination);
  connect(dstSocket, (struct sockaddr *) &dstAddr, sizeof(dstAddr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽo */
  for(i=0; i<10; i++) {
    printf("sending...\n");
    send(dstSocket, toSendText, strlen(toSendText)+1, 0);
    sleep(1);
  }

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽI�ｿｽ�ｿｽ */
  close(dstSocket);
}

UDP �ｿｽT�ｿｽ[�ｿｽo�ｿｽ�ｿｽ

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

#define BUFFER_SIZE 256

int
main() {
  /* �ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  unsigned short port = 9876;
  int recvSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in recvSockAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int status;
  int numrcv;
  char buffer[BUFFER_SIZE];
  unsigned long on = 1;

  /************************************************************/
  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&recvSockAddr, 0, sizeof(recvSockAddr));
  recvSockAddr.sin_port = htons(port);
  recvSockAddr.sin_family = AF_INET;
  recvSockAddr.sin_addr.s_addr = htonl(INADDR_ANY);

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  recvSocket = socket(AF_INET, SOCK_DGRAM, 0);
 
  /* �ｿｽo�ｿｽC�ｿｽ�ｿｽ�ｿｽh */
  status = bind(recvSocket, (struct sockaddr_in *) &recvSockAddr, sizeof(recvSockAddr));

  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽM */
  while(1) {
    numrcv = recvfrom(recvSocket, buffer, BUFFER_SIZE, 0, NULL, NULL);
    if(numrcv == -1) { status = close(recvSocket); break; }
    printf("received: %s\n", buffer);
  }
}

UDP �ｿｽN�ｿｽ�ｿｽ�ｿｽC�ｿｽA�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ

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

int
main() {
  /* IP�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽA�ｿｽ|�ｿｽ[�ｿｽg�ｿｽﾔ搾ｿｽ�ｿｽA�ｿｽ\�ｿｽP�ｿｽb�ｿｽg */
  char destination[80];
  unsgined short port = 9876;
  int destSocket;

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  struct sockaddr_in destSockAddr;

  /* �ｿｽe�ｿｽ�ｿｽp�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽ^ */
  int i;
  char *toSendText = "This is a test";

  /************************************************************/
  /* �ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽA�ｿｽh�ｿｽ�ｿｽ�ｿｽX�ｿｽﾌ難ｿｽ�ｿｽ�ｿｽ */
  printf("Connect to ? : (name or IP address) ");
  scanf("%s", destination);

  /* sockaddr_in �ｿｽ\�ｿｽ�ｿｽ�ｿｽﾌのセ�ｿｽb�ｿｽg */
  memset(&destSockAddr, 0, sizeof(destSockAddr));
  destSockAddr.sin_addr.s_addr = inet_addr(destination);
  destSockAddr.sin_port = htons(port);
  destSockAddr.sin_family = AF_INET;

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ */
  destSocket = socket(AF_INET, SOCK_DGRAM, 0);
 
  /* �ｿｽp�ｿｽP�ｿｽb�ｿｽg�ｿｽ�ｿｽ�ｿｽo */
  for(i=0; i<10; i++) {
    printf("sending...\n");
    sendto(destSocket, toSendText, strlen(toSendText)+1, 0, &destSockAddr, sizeof(destSockAddr));
    sleep(1);
  }

  /* �ｿｽ\�ｿｽP�ｿｽb�ｿｽg�ｿｽﾌ終�ｿｽ�ｿｽ */
  close(destSocket);
}