Question

这是我的c服务器端代码。我正在向java上的客户端发送问候

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include<errno.h>
#include<arpa/inet.h>

#define PORT 6865
#define BUF 256

int main(int argc, char *argv[])
{
 struct sockaddr_in host, remote;
 int host_fd, remote_fd;
 int size = sizeof(struct sockaddr);;

int read_t,i;
char data[]="hello";

host.sin_family = AF_INET;
host.sin_addr.s_addr = htonl(INADDR_ANY);
host.sin_port = htons(PORT);
memset(&host.sin_zero, 0, sizeof(host.sin_zero));

host_fd = socket(AF_INET, SOCK_STREAM, 0);
if(host_fd == -1) {
    printf("socket error %d\n", host_fd);
    return 1;
}

if(bind(host_fd, (struct sockaddr *)&host, size)) {
    perror("bind error is\n");
printf("errorno is %d\n",errno);
    return 1;
}

if(listen(host_fd, 10)) {
    printf("listen error");
    return 1;
}

printf("Server setup, waiting for connection...\n");
remote_fd = accept(host_fd, (struct sockaddr *)&remote, &size);

printf("connection made\n");

//read_t = recv(remote_fd,data,sizeof(data),0);
//data[read_t]='\0';
printf("read = %d, data = %s \n", sizeof(data), data);
if(sendto(remote_fd,data,sizeof(data),0,NULL,1)==-1)
{
    printf("error in sending back\n");
    return 1;
}
    read_t = recv(remote_fd,data,sizeof(data),0);
data[read_t]='\0';
    printf("read = %d, received_data = %s \n", sizeof(data), data);
shutdown(remote_fd, SHUT_RDWR);
close(remote_fd);

return 0;
}

这是java代码

  package com.java.client;

 import java.io.BufferedInputStream;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;
 import java.net.Socket;
 import java.net.UnknownHostException;
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;

  public class ClientFirst
  {
 public static void main(String[] argv) throws UnknownHostException, IOException 
 {
     char[] data = new char[10];
     Socket s = new Socket("10.9.79.80", 6865);


     InputStreamReader ins= new  InputStreamReader(s.getInputStream());
         int da= ins.read(data, 0, 9);
         System.out.print(Integer.toString(da));

    }
 }

当我试图从c服务器接收数据时，我没有得到它。而不是打招呼，我得到5。

Answer 1

尝试打印data变量，而不是变量InputStreamReader.read中da的返回值，如下所示：

System.out.print(data);

InputStreamReader.read代替返回读取的字符数。

Answer 2

您正在打印从流中读取的字符数，而不是实际读取的数据。试试这个：

int da = ins.read(data, 0, 9);
System.out.print( data );

干杯，

Answer 3

da为5，因为您从套接字读取了五个字节。 hello由5个字节组成，因此一切正常。您收到的信件已存储在变量data。

中

无法从服务器接收数据

3 个答案: