IP地址转换函数

#include<string.h>
#include<arpa/inet.h>
#include<stdio.h>
int main(void){
  char ip[]="1.2.3.4";//字符串
  struct sockaddr_in server_addr;
  inet_pton(AF_INET,ip,&server_addr.sin_addr.s_addr);//字符串 to 网络字节序
  printf("s_addr : %x\n",server_addr.sin_addr.s_addr);
  printf("s_addr from to host : %x\n",ntohl(server_addr.sin_addr.s_addr));//网络字节序 to 主机字节序
  char server_ip[64];
  inet_ntop(AF_INET,&server_addr.sin_addr.s_addr,server_ip,64);//网络字节序 to 字符串
  printf("server ip : %s\n",server_ip);
  return 0;
}