这是我在 Heroku 和 AppFog 上托管的 node.js TCP 服务器的代码。我的客户端是用 C 语言编写的,它只是向服务器发送一条消息并获得响应。当我在本地托管服务器时,它们工作正常。但是当我尝试连接到在线服务器时,客户端失败(“连接错误:操作超时”)。知道发生了什么吗?
服务器(node.js):
var net = require('net');
var server = net.createServer(function (socket) {
socket.on("data", function(data){
socket.write(data.toString());
});
});
var port = process.env.VCAP_APP_PORT || 8081;
console.log(port);
server.listen(port);
客户端(C,来自http://www.linuxhowtos.org/C_C++/socket.htm):
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
void error(const char *msg)
{
perror(msg);
exit(0);
}
int main(int argc, char *argv[])
{
int sockfd, portno, n;
struct sockaddr_in serv_addr;
struct hostent *server;
char buffer[256];
if (argc < 3) {
fprintf(stderr,"usage %s hostname port\n", argv[0]);
exit(0);
}
portno = atoi(argv[2]);
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
error("ERROR opening socket");
server = gethostbyname(argv[1]);
if (server == NULL) {
fprintf(stderr,"ERROR, no such host\n");
exit(0);
}
bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
bcopy((char *)server->h_addr,
(char *)&serv_addr.sin_addr.s_addr,
server->h_length);
serv_addr.sin_port = htons(portno);
if (connect(sockfd,(struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0)
error("ERROR connecting");
while (1){
printf("Please enter the message: ");
bzero(buffer,256);
fgets(buffer,255,stdin);
n = write(sockfd,buffer,strlen(buffer));
if (n < 0)
error("ERROR writing to socket");
bzero(buffer,256);
n = read(sockfd,buffer,255);
if (n < 0)
error("ERROR reading from socket");
printf("%s\n",buffer);
}
close(sockfd);
return 0;
}