标签：puts 服务器 main 传递数据 code class tar win rcm
udp是具有数据边界的协议，传输中调用I/O函数的次数非常重要。输入函数的调用次数要和输出函数的调用次数完全一致，这样才能保证接受全部已发送的数据。
tcp套接字中需注册待传输数据的目标IP和端口，而udp中无需注册。通过sendto函数传递数据的过程大约分为3个阶段：
第1阶段：向udp套接字注册目标IP和端口号。
第2阶段：传输数据。
第3阶段：删除udp套接字中注册的目标地址信息。
每次调用sendto函数时都会重复上述过程。这种未注册目标地址信息的套接字成为未连接套接字，反之，注册了目标地址的套接字称为连接套接字。udp默认属于未连接套接字，创建已连接udp套接字只需调用connect函数，这样可以提高效率。
服务器端：
#include
#include
#include #define BUF_SIZE 64
void ErrorHandling(char* message);
int main()
{
WSADATA wsa_data;
SOCKET server_sock;
SOCKADDR_IN server_addr, client_addr;
int sz_client_addr;
char message[BUF_SIZE];
int str_len;
if (WSAStartup(MAKEWORD(2, 2), &wsa_data) != 0)
ErrorHandling("WSAStartup() error.");
server_sock = socket(PF_INET, SOCK_DGRAM, 0);
if (server_sock == INVALID_SOCKET)
ErrorHandling("socket() error.");
memset(&server_addr, 0, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
server_addr.sin_port = htons(8000);
if (bind(server_sock, (SOCKADDR*)&server_addr, sizeof(server_addr)) == SOCKET_ERROR)
ErrorHandling("bind() error.");
while (true)
{
sz_client_addr = sizeof(client_addr);
str_len = recvfrom(server_sock, message, BUF_SIZE, 0, (SOCKADDR*)&client_addr, &sz_client_addr);
sendto(server_sock, message, str_len, 0, (SOCKADDR*)&client_addr, sizeof(message));
}
closesocket(server_sock);
WSACleanup();
return 0;
}
void ErrorHandling(char* message)
{
fputs(message, stderr);
fputc(‘\n‘, stderr);
exit(1);
}
使用连接套接字的客户端：
#include
#include
#include #define BUF_SIZE 64
void ErrorHandling(char* message);
int main()
{
WSADATA wsa_data;
SOCKET h_socket;
SOCKADDR_IN server_addr;
char message[BUF_SIZE];
int str_len;
if (WSAStartup(MAKEWORD(2, 2), &wsa_data) != 0)
ErrorHandling("WSAStartup() error.");
h_socket = socket(PF_INET, SOCK_DGRAM, 0);
if (h_socket == INVALID_SOCKET)
ErrorHandling("socket() error.");
memset(&server_addr, 0, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
server_addr.sin_port = htons(8000);
if (connect(h_socket, (SOCKADDR*)&server_addr, sizeof(server_addr)) == SOCKET_ERROR)
ErrorHandling("connect() error.");
while (true)
{
fputs("Insert message(q to quit): ", stdout);
fgets(message, sizeof(message), stdin);
if (!strcmp(message, "q\n") || !strcmp(message, "Q\n"))
break;
send(h_socket, message, strlen(message), 0);
str_len = recv(h_socket, message, sizeof(message) - 1, 0);
message[str_len] = 0;
printf("Message from server: %s", message);
}
closesocket(h_socket);
WSACleanup();
return 0;
}
void ErrorHandling(char* message)
{
fputs(message, stderr);
fputc(‘\n‘, stderr);
exit(1);
}
使用未连接套接字的客户端：
#include
#include
#include #define BUF_SIZE 64
void ErrorHandling(char* message);
int main()
{
WSADATA wsa_data;
SOCKET h_socket;
SOCKADDR_IN server_addr, from_addr;
char message[BUF_SIZE];
int str_len;
if (WSAStartup(MAKEWORD(2, 2), &wsa_data) != 0)
ErrorHandling("WSAStartup() error.");
h_socket = socket(PF_INET, SOCK_DGRAM, 0);
if (h_socket == INVALID_SOCKET)
ErrorHandling("socket() error.");
memset(&server_addr, 0, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
server_addr.sin_port = htons(8000);
while (true)
{
fputs("Insert message(q to quit): ", stdout);
fgets(message, sizeof(message), stdin);
if (!strcmp(message, "q\n") || !strcmp(message, "Q\n"))
break;
sendto(h_socket, message, strlen(message), 0, (SOCKADDR*)&server_addr, sizeof(server_addr));
int sz_from_addr = sizeof(from_addr);
str_len = recvfrom(h_socket, message, BUF_SIZE, 0, (SOCKADDR*)&from_addr, &sz_from_addr);
message[str_len] = 0;
printf("Message from server: %s", message);
}
closesocket(h_socket);
WSACleanup();
return 0;
}
void ErrorHandling(char* message)
{
fputs(message, stderr);
fputc(‘\n‘, stderr);
exit(1);
}
基于windows的回声udp服务器端/客户端
标签：puts 服务器 main 传递数据 code class tar win rcm
原文地址：https://www.cnblogs.com/ACGame/p/9908215.html