printf("-ip11111----ip=%s", inet_ntoa(sender_address.sin_addr.s_addr));
时间: 2024-04-03 11:35:38 浏览: 21
这段代码的作用是将一个IP地址转换成字符串格式,并输出到控制台上。具体来说,inet_ntoa函数将in_addr结构体中存储的二进制IP地址转换成点分十进制格式的字符串,然后通过%s格式符输出到控制台上。其中,sender_address.sin_addr.s_addr是一个32位的无符号整型数,表示发送方的IP地址。
相关问题
怎么打印sender_address.sin_addr.s_addr
sender_address.sin_addr.s_addr 是一个无符号整数,表示 IP 地址。如果要打印 IP 地址,可以使用 inet_ntoa 函数将无符号整数转换成字符串格式,然后使用 printf 函数输出。示例代码如下:
```
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main() {
struct sockaddr_in sender_address;
sender_address.sin_family = AF_INET;
sender_address.sin_addr.s_addr = inet_addr("192.168.0.1");
printf("IP address: %s\n", inet_ntoa(sender_address.sin_addr));
return 0;
}
```
输出结果为:
```
IP address: 192.168.0.1
```
用c语言写一个报文交互案例
好的,以下是一个简单的报文交互案例:
#include <stdio.h>
#include <string.h>
int main() {
// 定义发送方和接收方的地址和端口
char sender_ip[] = "127.0.0.1";
int sender_port = 8888;
char receiver_ip[] = "127.0.0.1";
int receiver_port = 8889;
// 创建发送方和接收方的socket
int sender_socket = socket(AF_INET, SOCK_DGRAM, 0);
int receiver_socket = socket(AF_INET, SOCK_DGRAM, 0);
// 绑定发送方和接收方的地址和端口
struct sockaddr_in sender_addr, receiver_addr;
sender_addr.sin_family = AF_INET;
sender_addr.sin_addr.s_addr = inet_addr(sender_ip);
sender_addr.sin_port = htons(sender_port);
receiver_addr.sin_family = AF_INET;
receiver_addr.sin_addr.s_addr = inet_addr(receiver_ip);
receiver_addr.sin_port = htons(receiver_port);
bind(sender_socket, (struct sockaddr *)&sender_addr, sizeof(sender_addr));
bind(receiver_socket, (struct sockaddr *)&receiver_addr, sizeof(receiver_addr));
// 发送方向接收方发送消息
char send_buf[1024] = "Hello, receiver!";
sendto(sender_socket, send_buf, strlen(send_buf) + 1, 0, (struct sockaddr *)&receiver_addr, sizeof(receiver_addr));
// 接收方接收消息并回复消息
char recv_buf[1024];
struct sockaddr_in sender_sockaddr;
int sender_sockaddr_size = sizeof(sender_sockaddr);
recvfrom(receiver_socket, recv_buf, sizeof(recv_buf), 0, (struct sockaddr *)&sender_sockaddr, &sender_sockaddr_size);
printf("Received message from %s:%d: %s\n", inet_ntoa(sender_sockaddr.sin_addr), ntohs(sender_sockaddr.sin_port), recv_buf);
char reply_buf[1024] = "Hello, sender!";
sendto(receiver_socket, reply_buf, strlen(reply_buf) + 1, 0, (struct sockaddr *)&sender_sockaddr, sizeof(sender_sockaddr));
// 关闭发送方和接收方的socket
close(sender_socket);
close(receiver_socket);
return 0;
}