我正在尝试编写一个 TCP Echo 程序，它应该打开一个 TCP 服务器套接字，接受至少 1 个连接，并回显接收到的任何数据。至少，该程序应在指定端口（exe：端口 4444" 上启动并运行。理想情况下，它会询问端口号（来自命令行、命令行参数或配置文件），尝试在该端口上打开，并报告是否发生错误。
该程序应该使用 windows 或 Linux 中的 telnet 命令或任何操作系统中的任何终端仿真器进行测试。用户使用 Telnet 或超级终端连接到正在运行的程序。输入的任何内容都应立即回显。
到目前为止，我有以下内容：
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>
#include <errno.h>
#define MAXCONNECTING 1000 //Max connection requests
#define BUFFERSIZE 128 //limits data sent per loop
#define ECHOPORT 4444
//Error checking function
//Will be called multiple times to check for errors throughout the code
void ERR(char *ERROR) {
perror(ERROR);
exit(1);
}
/****************************************************************************
* Handles the connection. Receive/Send data from/to client
****************************************************************************/
void ClientHandle(int sock) {
char buffer[BUFFERSIZE];
int received = -1;
//receive the data
if ((received = recv(sock, buffer, BUFFERSIZE, 0)) < 0) {
ERR("Failed to receive message from client");
}
//send data and check for more incoming data
while (received > 0) {
if (send(sock, buffer, received, 0) != received) {
ERR("Failed to send data to client");
}
if ((received = recv(sock, buffer, BUFFERSIZE, 0)) < 0) {
ERR("Failed to receive additional data from client");
}
}
close(sock);
}
int main(int argc, char *argv[]) {
/****************************************************************************
* Get port number from command line and set to default port
****************************************************************************/
char *endptr;
short int port;
if (argc == 2) {
port = strtol(argv[1], &endptr, 0);
if (*endptr) {
fprintf(stderr, "EchoServer: Invalid Port Number.\n");
exit(EXIT_FAILURE);
}
} else if (argc < 2) {
port = ECHOPORT; //port 4444
} else {
fprintf(stderr, "EchoServer: Invalid arguments.\n");
exit(EXIT_FAILURE);
}
/****************************************************************************
* Server Configuration. Creating the socket
****************************************************************************/
int serversock, clientsock;
struct sockaddr_in echoserver, echoclient;
if (argc != 2) {
fprintf(stderr, "USING: echoserver Port: 4444\n");
exit(1);
}
//Creating the TCP socket
if ((serversock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
ERR("Failed to create socket");
}
//Constructing the server sockaddr_in structure
memset(&echoserver, 0, sizeof(echoserver)); //clear struct
echoserver.sin_family = AF_INET; //internet ip
echoserver.sin_addr.s_addr = htonl(INADDR_ANY); //listen to any ip address
echoserver.sin_port = htons(atoi(argv[1])); //server port
/*****************************************************************************
* Bind and Listen
*****************************************************************************/
if (bind(serversock, (struct sockaddr *) &echoserver, sizeof (echoserver)) < 0) {
ERR("Failed to bind the server socket");
}
if (listen(serversock, MAXCONNECTING) < 0) {
ERR("Failed to listen on server socket");
}
/*****************************************************************************
* Accepting the transmission
*****************************************************************************/
while (1) {
unsigned int clientleng = sizeof (echoclient);
if ((clientsock = accept(serversock, (struct sockaddr *) &echoclient, &clientleng)) < 0) {
ERR("Failed to accept connection from client");
}
fprintf(stdout, "Client connected: %s\n", inet_ntoa(echoclient.sin_addr));
ClientHandle(clientsock);
}
return (0);
}
/*****************************************************************************************/
谁能看到我哪里出错了？我可以使用以下命令在终端中找到程序：g++ EchoServer.cpp -0 EchoServer，然后是：./EchoServer
输出只给我： USING: echoserver Port: 4444
我正在尝试远程登录它，但我对这些东西很陌生。请帮忙！！