基本TCPソケット２−４
getsockname関数とgetpeername関数
#include <sys/socket.h> int getsockname(int sockfd, struct sockaddr *localaddr, socklen_t *addrlen); int getpeername(int sockfd, struct sockaddr *peeraddr, socklen_t *addrlen); 戻り値：成功 → 0, エラー → -1
getsocknameサンプル
#include <sys/socket.h>
#include <sys/types.h>
#include <stdio.h>#include <arpa/inet.h>
int
main()
{
int sockfd;
struct sockaddr_in addr;
struct sockaddr_in sockname;
socklen_t addr_len = sizeof(sockname);
int sockname_len = sizeof(sockname);
sockfd = socket(AF_INET, SOCK_STREAM, 0);
addr.sin_family = AF_INET;
addr.sin_port = htons(80);
addr.sin_addr.s_addr = inet_addr("192.168.10.254");//接続先IPアドレスを指定する
connect(sockfd, (struct sockaddr*)&addr, addr_len);
getsockname(sockfd, (struct sockaddr*)&sockname, &sockname_len);
printf("IP Address = %s, Port Number = %d\n",
inet_ntoa(sockname.sin_addr), ntohs(sockname.sin_port));
return 0;
}getpeername サンプル
#include <stdio.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <arpa/inet.h>
int
main()
{
int listenfd, connfd;
struct sockaddr_in addr;
struct sockaddr_in client_addr;
struct sockaddr_in peer;
int client_addr_len = sizeof(client_addr);
socklen_t peer_len = sizeof(peer);
listenfd = socket(AF_INET, SOCK_STREAM, 0);
addr.sin_family = AF_INET;
addr.sin_port = htons(8000);
addr.sin_addr.s_addr = htonl(INADDR_ANY);
bind(listenfd, (struct sockaddr*)&addr, sizeof(addr));
listen(listenfd, 64);
connfd = accept(listenfd, (struct sockaddr*)&client_addr, &client_addr_len);
getpeername(connfd, (struct sockaddr*)&peer, &peer_len);
printf("IP Address=%s, Port=%d\n",
inet_ntoa(peer.sin_addr), ntohs(peer.sin_port));
return 0;
}参考文献
