#include <stdlib.h>
#include <string.h>
#include <vector>
#ifdef WIN32
#include <WinSock2.h>
#include <ws2tcpip.h>
#pragma comment(lib,"Ws2_32.lib")
//end WIN32
#else //Linux
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#endif //end Linux
typedef std::vector<struct in_addr> array_in_addr;
int GetHostsByName( const char *host_name,array_in_addr* pArrayaddr)
{
int n=0;
struct addrinfo hints,*res;
struct addrinfo* p_addrinfo = NULL;
memset( &hints,0,sizeof(struct addrinfo) );
hints.ai_flags = AI_CANONNAME; //瀹㈡埛绔竴鑸氨鐢ㄨ繖涓?nbsp;AI_CANONNAME,鏈嶅姟绔緩璁敤:AI_PASSIVE
hints.ai_family = AF_INET; //AF_INET:IPv4 ,AF_INET6:IPv6
hints.ai_socktype = SOCK_STREAM; //IPPROTO_IP 鍙兘浼氫駭鐢熷涓噸澶岻P
sockaddr_in* p_sockaddr_in;
if( (n = getaddrinfo( host_name,NULL, &hints, &res) ) != 0)
return 0;
printf("domain:%s \r\n",host_name);
p_addrinfo = res;
while(p_addrinfo!=NULL)
{
pArrayaddr->push_back( ((sockaddr_in*)p_addrinfo->ai_addr)->sin_addr);
printf("ip%d: %s \r\n",pArrayaddr->size(),inet_ntoa(((sockaddr_in*)p_addrinfo->ai_addr)->sin_addr));
p_addrinfo = p_addrinfo->ai_next;
}
freeaddrinfo(res);
return pArrayaddr->size();
}
int main(int argc, char *argv[])
{
int nRet;
const char* pszHost = NULL;
array_in_addr inaddrs;
if (argc != 2) {
printf("Usage:%s <hostname> \r\n",argv[0]);
return -1;
}
pszHost = argv[1];
#ifdef WIN32
WSADATA wsaData;
int err = WSAStartup( 0x0202, &wsaData );
if ( err != 0 ) {
printf("socket init(WSAStartup) failure \r\n");
return 1;
}
#endif
GetHostsByName(pszHost,&inaddrs);
#ifdef WIN32
WSACleanup();
#endif
return 0;
}
鍙傝緗戝潃:
http://baike.baidu.com/view/6757218.htm
]]>
]]>
//瀹㈡埛绔唬鐮?nbsp;62.cpp
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#define PORT 1234 /* Port that will be opened */
#define BACKLOG 5 /* Number of allowed connections */
#define MAXDATASIZE 4096
void process_cli(int connectfd,struct sockaddr_in client);
int main() {
int listenfd, connectfd; /* socket descriptors */
struct sockaddr_in server; /* server's address information */
struct sockaddr_in client; /* client's address information */
socklen_t sin_size;
/* Create TCP socket */
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
/* handle exception */
perror("Creating socket failed.\n");
exit(1);
}
int opt = SO_REUSEADDR;
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
bzero(&server,sizeof(server));
server.sin_family=AF_INET;
server.sin_port=htons(PORT);
server.sin_addr.s_addr = htonl (INADDR_ANY);
if (bind(listenfd, (struct sockaddr *)&server, sizeof(struct sockaddr)) == -1) {
/* handle exception */
perror("Bind error.\n");
exit(1);
}
if(listen(listenfd,BACKLOG) == -1){ /* calls listen() */
perror("listen() error\n");
exit(1);
}
sin_size=sizeof(struct sockaddr_in);
while (1) {
if ((connectfd = accept(listenfd,(struct sockaddr *)&client,&sin_size))==-1) {
perror("accept() error\n");
exit(1);
}
process_cli(connectfd, client);
}
close(listenfd);
}
void process_cli(int connectfd, struct sockaddr_in client)
{
int num;
char recvbuf[MAXDATASIZE], sendbuf[MAXDATASIZE];
/* prints client's IP */
printf("%s:%d Client was connected\n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
while (1) {
num = recv(connectfd, recvbuf, MAXDATASIZE,0);
if (num == 0) {
close(connectfd);
printf("%s:%d Client was disconnected \n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
break;
}
if (num == -1) {
perror("recv() error\n");
break;
}
printf("recvbuf[0]:%d,recvbuf[num-1]:%d,num:%d\n",recvbuf[0],recvbuf[num-1],num);
recvbuf[num] = '\0';
printf("Received message From Client : %s\n",recvbuf);
for (int i = 0; i < num; i++) {
sendbuf[i] = recvbuf[num-i-1];
//printf("sendbuf[%d]:%d\n",i,sendbuf[i]);
}
//printf("sendbuf[0]:%d,sendbuf[num-1]:%d,num:%d\n",sendbuf[0],sendbuf[num-1],num);
send(connectfd,sendbuf,num,0); /* send to the client welcome message */
}
close(connectfd); /* close connectfd */
}
]]>
//瀹㈡埛绔唬鐮?nbsp;62.cpp
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#define PORT 1234 /* Port that will be opened */
#define BACKLOG 5 /* Number of allowed connections */
#define MAXDATASIZE 4096
void process_cli(int connectfd,struct sockaddr_in client);
int main()
{
int listenfd, connectfd; /* socket descriptors */
pid_t pid;
struct sockaddr_in server; /* server's address information */
struct sockaddr_in client; /* client's address information */
socklen_t sin_size;
/* Create TCP socket */
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
/* handle exception */
perror("Creating socket failed.\n");
exit(1);
}
int opt = SO_REUSEADDR;
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
bzero(&server,sizeof(server));
server.sin_family=AF_INET;
server.sin_port=htons(PORT);
server.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(listenfd, (struct sockaddr *)&server, sizeof(struct sockaddr)) == -1) {
/* handle exception */
perror("Bind error.\n");
exit(1);
}
if(listen(listenfd,BACKLOG) == -1){ /* calls listen() */
perror("listen() error\n");
exit(1);
}
sin_size=sizeof(struct sockaddr_in);
while(1)
{
/*accept connection */
if ((connectfd = accept(listenfd,(struct sockaddr *)&client,&sin_size))==-1) {
perror("accept() error\n");
exit(1);
}
/* Create child process to service client */
if ((pid=fork())>0) {
/* parent process */
close(connectfd);
continue;
}
else if (pid==0) {
/*child process*/
close(listenfd);
process_cli(connectfd, client);
exit(0);
}
else {
perror("fork() error\n");
exit(0);
}
}
close(listenfd); /* close listenfd */
}
void process_cli(int connectfd, struct sockaddr_in client)
{
int num;
char recvbuf[MAXDATASIZE], sendbuf[MAXDATASIZE];
/* prints client's IP */
printf("%s:%d Client was connected\n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
while (1) {
num = recv(connectfd, recvbuf, MAXDATASIZE,0);
if (num == 0) {
close(connectfd);
printf("%s:%d Client was disconnected \n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
break;
}
if (num == -1) {
perror("recv() error\n");
break;
}
printf("recvbuf[0]:%d,recvbuf[num-1]:%d,num:%d\n",recvbuf[0],recvbuf[num-1],num);
recvbuf[num] = '\0';
printf("Received message From Client : %s\n",recvbuf);
for (int i = 0; i < num; i++) {
sendbuf[i] = recvbuf[num-i-1];
//printf("sendbuf[%d]:%d\n",i,sendbuf[i]);
}
//printf("sendbuf[0]:%d,sendbuf[num-1]:%d,num:%d\n",sendbuf[0],sendbuf[num-1],num);
send(connectfd,sendbuf,num,0); /* send to the client welcome message */
}
close(connectfd); /* close connectfd */
}
]]>
//g++ -o 64 64.cpp -lpthread
//瀹㈡埛绔唬鐮?nbsp;62.cpp
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#define PORT 1234 /* Port that will be opened */
#define BACKLOG 5 /* Number of allowed connections */
#define MAXDATASIZE 4096
void process_cli(int connectfd,struct sockaddr_in client);
/* function to be executed by the new thread */
void* start_routine(void* arg);
struct ARG {
int connfd;
sockaddr_in client;
};
int main()
{
int listenfd, connectfd; /* socket descriptors */
pthread_t thread;
ARG *arg;
struct sockaddr_in server; /* server's address information */
struct sockaddr_in client; /* client's address information */
socklen_t sin_size;
/* Create TCP socket */
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
/* handle exception */
perror("Creating socket failed.\n");
exit(1);
}
int opt = SO_REUSEADDR;
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
bzero(&server,sizeof(server));
server.sin_family=AF_INET;
server.sin_port=htons(PORT);
server.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(listenfd, (struct sockaddr *)&server, sizeof(struct sockaddr)) == -1) {
/* handle exception */
perror("Bind error.");
exit(1);
}
if(listen(listenfd,BACKLOG) == -1){ /* calls listen() */
perror("listen() error\n");
exit(1);
}
sin_size=sizeof(struct sockaddr_in);
while(1)
{
/* Accept connection */
if ((connectfd = accept(listenfd,(struct sockaddr *)&client,&sin_size))==-1) {
perror("accept() error\n");
exit(1);
}
/* Create thread*/
arg = new ARG;
arg->connfd = connectfd;
memcpy((void *)&arg->client, &client, sizeof(client));
if (pthread_create(&thread, NULL, start_routine, (void*)arg)) {
/* handle exception */
perror("Pthread_create() error");
exit(1);
}
}
close(listenfd); /* close listenfd */
}
void process_cli(int connectfd, struct sockaddr_in client)
{
int num;
char recvbuf[MAXDATASIZE], sendbuf[MAXDATASIZE];
/* prints client's IP */
printf("%s:%d Client was connected\n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
while (1) {
num = recv(connectfd, recvbuf, MAXDATASIZE,0);
if (num == 0) {
close(connectfd);
printf("%s:%d Client was disconnected \n",inet_ntoa(client.sin_addr), ntohs( client.sin_port) );
break;
}
if (num == -1) {
perror("recv() error\n");
break;
}
printf("recvbuf[0]:%d,recvbuf[num-1]:%d,num:%d\n",recvbuf[0],recvbuf[num-1],num);
recvbuf[num] = '\0';
printf("Received message From Client : %s\n",recvbuf);
for (int i = 0; i < num; i++) {
sendbuf[i] = recvbuf[num-i-1];
//printf("sendbuf[%d]:%d\n",i,sendbuf[i]);
}
//printf("sendbuf[0]:%d,sendbuf[num-1]:%d,num:%d\n",sendbuf[0],sendbuf[num-1],num);
send(connectfd,sendbuf,num,0); /* send to the client welcome message */
}
close(connectfd); /* close connectfd */
}
void* start_routine(void* arg)
{
ARG *info;
info = (ARG *)arg;
/* handle client’s requirement */
process_cli(info->connfd, info->client);
delete (ARG*)arg;
pthread_exit(NULL);
}
]]>
#include <iostream>
#include <map>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <bitset>
using namespace std;
#define PORT 1234 /* Port that will be opened */
#define BACKLOG 5 /* Number of allowed connections */
#define MAXDATASIZE 4096
typedef map<unsigned int,sockaddr_in> connects;
void process_cli(int sockfd,sockaddr_in addr,char* recvbuf, int len);
void reverser(char* szIn,char* szOut,unsigned int nLen)
{
for (int i=0;i<nLen;i++) {
szOut[i] = szIn[nLen-i-1];
}
}
int main()
{
connects connect_fds;
int sock_fd;
ssize_t recv_size;
fd_set read_set;
fd_set all_set;
int listen_fd;
int connect_fd;
int ready_size;
socklen_t addr_size;
sockaddr_in srv_addr;
sockaddr_in addr;
unsigned int max_fd = 0;
char recv_buf[MAXDATASIZE];
if ((listen_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("Creating socket failed.");
exit(1);
}
int opt = SO_REUSEADDR;
setsockopt(listen_fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
bzero(&srv_addr,sizeof(srv_addr));
srv_addr.sin_family=AF_INET;
srv_addr.sin_port=htons(PORT);
srv_addr.sin_addr.s_addr = htonl (INADDR_ANY);
if (bind(listen_fd, (struct sockaddr *)&srv_addr, sizeof(struct sockaddr)) == -1) {
perror("Bind error.");
exit(1);
}
if(listen(listen_fd,BACKLOG) == -1) {
perror("listen() error\n");
exit(1);
}
max_fd = listen_fd;
addr_size=sizeof(sockaddr_in);
FD_ZERO(&all_set);
FD_SET(listen_fd, &all_set);
connects::iterator iter;
printf("clients:(%u) ,current listen socket:%u\n",connect_fds.size(),listen_fd);
while(1)
{
read_set = all_set;
ready_size = select(max_fd+1, &read_set, NULL, NULL, NULL);
if ( FD_ISSET(listen_fd,&read_set) ) {
connect_fd = accept(listen_fd,(struct sockaddr *)&addr,&addr_size);
if (connect_fd ==-1 ) {
perror("accept() error\n");
continue;
}
connect_fds[connect_fd] = addr;
max_fd = connect_fd;
FD_SET(connect_fd, &all_set);
printf("clients:(%u) ,%s:%d connected ,connect socket:%u\n",connect_fds.size(),inet_ntoa(addr.sin_addr),ntohs(addr.sin_port),connect_fd);
}
for ( iter = connect_fds.begin(); iter!=connect_fds.end(); iter++) {
sock_fd = iter->first;
addr = iter->second;
if ( FD_ISSET(sock_fd,&read_set) ) {
recv_size = recv(sock_fd, recv_buf, MAXDATASIZE,0);
if ( recv_size == 0) {
close(sock_fd);
FD_CLR(sock_fd, &all_set);
connect_fds.erase(sock_fd);
printf("%s:%d disconnected\n",inet_ntoa(addr.sin_addr),ntohs(addr.sin_port) );
}
else {
process_cli(sock_fd,addr,recv_buf,recv_size);
}
}
}
}
close(listen_fd);
}
void process_cli(int sockfd,sockaddr_in addr,char* recvbuf, int len)
{
char sendbuf[MAXDATASIZE];
printf("Received %s:%d message: %s\n",inet_ntoa(addr.sin_addr),ntohs(addr.sin_port), recvbuf);
reverser(recvbuf,sendbuf,len);
printf("Send To %s:%d message: %s\n",inet_ntoa(addr.sin_addr),ntohs(addr.sin_port), sendbuf);
send(sockfd,sendbuf,len,0);
}
]]>
銆銆/* Create new stream socket */
銆銆sock = socket ( AF_INET, SOCK_STREAM, 0 );
銆銆/* Disable the Nagle (TCP No Delay) algorithm */
銆銆flag = 1;
銆銆int ret = setsockopt ( sock, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(flag) );
銆銆if (ret == -1) {
銆銆 printf("Couldn't setsockopt(TCP_NODELAY)\n");
銆銆 exit(-1);
銆銆}
]]>
瀛楄妭欏哄簭鏄寚鍗犲唴瀛樺浜庝竴涓瓧鑺傜被鍨嬬殑鏁版嵁鍦ㄥ唴瀛樹腑鐨勫瓨鏀鵑『搴忥紝閫氬父鏈夊皬绔佸ぇ绔袱縐嶅瓧鑺傞『搴忋?/span>
灝忕瀛楄妭搴忔寚浣庡瓧鑺傛暟鎹瓨鏀懼湪鍐呭瓨浣庡湴鍧澶勶紝楂樺瓧鑺傛暟鎹瓨鏀懼湪鍐呭瓨楂樺湴鍧澶勶紱
澶х瀛楄妭搴忔槸楂樺瓧鑺傛暟鎹瓨鏀懼湪浣庡湴鍧澶勶紝浣庡瓧鑺傛暟鎹瓨鏀懼湪楂樺湴鍧澶勩?/span>
鍩轟簬X86騫沖彴鐨?/font>PC鏈烘槸灝忕瀛楄妭搴忕殑
緗戠粶瀛楄妭搴? MSB 楂樺瓧鑺傚墠瀛樻硶 Most Significant Bit (Big Edian)
涓繪満瀛楄妭搴? LSB 浣庡瓧鑺傚墠瀛樻硶 Lest Significant Bit (Little Edian)
鍥犱負鐜拌鐨勮綆楁満閮芥槸浠ュ叓浣嶄竴涓瓧鑺備負瀛樺偍鍗曚綅錛岄偅涔堜竴涓?6浣嶇殑鏁存暟錛屼篃灝辨槸C璇█涓殑short錛屽湪鍐呭瓨涓彲鑳芥湁涓ょ瀛樺偍欏哄簭big-endian鍜宭itte-endian銆傝冭檻涓涓猻hort鏁存暟0x3132(0x32鏄綆浣嶏紝0x31鏄珮浣?錛屾妸瀹冭祴鍊肩粰涓涓猻hort鍙橀噺錛岄偅涔堝畠鍦ㄥ唴瀛樹腑鐨勫瓨鍌ㄥ彲鑳芥湁濡備笅涓ょ鎯呭喌錛?br />鍙互鍋氫釜瀹為獙鍦╓indows涓婁笅濡備笅紼嬪簭#include <stdio.h>#include <assert.h>int main(void)
{
short test; FILE* fp; 
test = 0x3132; /* (31ASIIC鐮佺殑'1', 32ASIIC鐮佺殑'2') */ if ((fp = fopen("c:\\test.txt", "wb")) == NULL) assert(0); fwrite(&test, sizeof(short), 1, fp); fclose(fp); return 0;
} 鐒跺悗鍦–鐩樹笅鎵撳紑test.txt鏂囦歡錛屽彲浠ョ湅瑙佸唴瀹規槸21錛岃宼est絳変簬0x3132錛屽彲浠ユ槑鏄劇殑鐪嬪嚭鏉86鐨勫瓧鑺傞『搴忔槸浣庝綅鍦ㄥ墠銆傚鏋滄垜浠妸榪欐鍚屾牱鐨勪唬鐮佹斁鍒?big-endian)鐨勬満鍣ㄤ笂鎵ц錛岄偅涔堟墦鍑烘潵鐨勬枃浠跺氨鏄?2銆傝繖鍦ㄦ湰鏈轟腑浣跨敤鏄病鏈夐棶棰樼殑銆備絾褰撲綘鎶婅繖涓枃浠朵粠涓涓猙ig-endian鏈哄櫒澶嶅埗鍒頒竴涓猯ittle-endian鏈哄櫒涓婃椂灝卞嚭鐜伴棶棰樹簡銆?br /> 濡備笂榪頒緥瀛愶紝鎴戜滑鍦╞ig-endian鐨勬満鍣ㄤ笂鍒涘緩浜嗚繖涓猼est鏂囦歡錛屾妸鍏跺鍒跺埌little-endian鐨勬満鍣ㄤ笂鍐嶇敤fread璇誨埌涓涓猻hort閲岄潰錛屾垜浠緱鍒扮殑灝變笉鍐嶆槸0x3132鑰屾槸0x3231浜嗭紝榪欐牱璇誨埌鐨勬暟鎹氨鏄敊璇殑錛屾墍浠ュ湪涓や釜瀛楄妭欏哄簭涓嶄竴鏍風殑鏈哄櫒涓婁紶杈撴暟鎹椂闇瑕佺壒鍒皬蹇冨瓧鑺傞『搴忥紝鐞嗚В浜嗗瓧鑺傞『搴忓湪鍙互甯姪鎴戜滑鍐欏嚭縐繪琛屾洿楂樼殑浠ｇ爜銆?br />姝ｅ洜涓烘湁瀛楄妭欏哄簭鐨勫樊鍒紝鎵浠ュ湪緗戠粶浼犺緭鐨勬椂鍊欏畾涔変簡鎵鏈夊瓧鑺傞『搴忕浉鍏崇殑鏁版嵁閮戒嬌鐢╞ig-endian錛孊SD鐨勪唬鐮佷腑瀹氫箟浜嗗洓涓畯鏉ョ悊錛?br />#define ntohs(n) //緗戠粶瀛楄妭欏哄簭鍒頒富鏈哄瓧鑺傞『搴?nbsp;n浠ｈ〃net, h浠ｈ〃host, s浠ｈ〃short#define htons(n) //涓繪満瀛楄妭欏哄簭鍒扮綉緇滃瓧鑺傞『搴?nbsp;n浠ｈ〃net, h浠ｈ〃host, s浠ｈ〃short#define ntohl(n) //緗戠粶瀛楄妭欏哄簭鍒頒富鏈哄瓧鑺傞『搴?nbsp;n浠ｈ〃net, h浠ｈ〃host, s浠ｈ〃long#define htonl(n) //涓繪満瀛楄妭欏哄簭鍒扮綉緇滃瓧鑺傞『搴?nbsp;n浠ｈ〃net, h浠ｈ〃host, s浠ｈ〃long
test ]]>
#include <afxwin.h>
#include <Winsock2.h>
#pragma comment(lib,"Ws2_32.lib")
int main(){
sockaddr_in addrSock1;
addrSock1.sin_family = AF_INET;
addrSock1.sin_port = htons(5555);
addrSock1.sin_addr.s_addr = inet_addr("127.0.0.1");
sockaddr* addrSock2;
addrSock2 = (sockaddr*)&addrSock1;
u_long uPort1 = htons(5555);
u_long uPort2 = MAKEWORD(addrSock2->sa_data[0],addrSock2->sa_data[1]);
return 0;
}
//娉ㄦ剰 addSock2->sa_data[0],addSock2->sa_data[1]鍙奙AKEWORD
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