linux udp通信不成功，server收不到消息

Question

仅仅是一个 示例，可是先执行server 后执行 client ，server还是没有收到消息。问题出在哪里呢
Server.c
#include "server.h"

#define PORT 2345
#define IP "192.168.0.114"

int main (void)
{
int fd;
struct sockaddr_in servaddr, cliaddr;
char buf[BUFFER_SIZE];
socklen_t peerlen;

//建立socket连接
fd = socket(AF_INET, SOCK_DGRAM, 0);
if(fd == -1)
{
    printf("fd error!\n");
    return -1;
}

//设置sockaddr_in参数
bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(PORT);
servaddr.sin_addr.s_addr = inet_addr(IP);

//绑定
bind(fd, (struct sockaddr *)&servaddr, sizeof(servaddr));
if(bind < 0)
{
    printf("bind error~!\n");
    return -1;
}

//调用recvfroom，等待接收客户端数据
peerlen = sizeof(cliaddr);
while(1)
{
    printf("Begin recv!\n");
    recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr *)&cliaddr ,&peerlen);
    printf("recv form client %s \n", buf);

    strcpy(buf, "Welcome to server");
    sendto(fd, &buf, sizeof(buf), 0, (struct sockaddr *)&cliaddr ,peerlen);
}

close(fd);
return 0;

}

client.c:
#include "client.h"

#define PORT 2345
#define IP "192.168.0.114"

int main (void)
{
int fd;
struct sockaddr_in servaddr;
char buf[BUFFER_SIZE] = "Hello Server!";

//建立socket连接
fd = socket(AF_INET, SOCK_DGRAM, 0);

if(fd == -1)
{
    printf("fd error \n");
    exit(-1);
}

//设置sockaddr_in参数
bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(PORT);
servaddr.sin_addr.s_addr = inet_addr(IP);

//向服务器发送消息
sendto(fd, buf, sizeof(buf), 0 ,(struct sockaddr *)&servaddr,sizeof(servaddr));
printf("Send message to Sever!\n");
//接收服务器消息
printf("Begin recv!\n");
recvfrom(fd, buf, sizeof(buf), 0 ,NULL ,NULL);
if(recvfrom < 0)
{
    printf("recv error!\n");
    return 1;
}

printf("recv from Server %s \n", buf);


close(fd);
return 0;

}

Answer 1

先看看server有没有收到任何信息，然后就是客户端发送的时候，是否返回失败等。还有就是网络中防火墙等。IP地址是否正确