判断大端序小端序:
通常情况下,数值在内存中存储的方式有两种,一种是大尾字节序,另一种是小尾,比如0x01020304这样一个数值,如果用大尾方式存储,其存储方式为01 02 03 04而用小尾方式存储则是04 03 02 01,一般Windows操作系统兼容的CPU为小尾方式,而UNIX操作系统所兼容的CPU多为大尾方式,通过使用两种方法即可判断大小纬。
#include <stdio.h>#include <stdlib.h>#include <WinSock2.h>#pragma comment(lib, "ws2_32.lib")// 变量法判断void GetA(){ DWORD dwSmallNum = 0x01020304; if (*(BYTE *)&dwSmallNum == 0x04) printf("小端字节序 \n"); else printf("大端字节序 \n");}// 直接转换法判断void GetB(){ DWORD dwSmallNum = 0x01020304; if (dwSmallNum == htonl(dwSmallNum)) printf("大端字节序 \n"); else printf("小端字节序 \n");}int main(int argc, char *argv[]){ GetA(); GetB(); system("pause"); return 0;}利用域名获取IP:
通过使用winsocket库中的gethostbyname()可以将一个域名所对应的别名,地址类型等信息提取出来。
#include <stdio.h>#include <stdlib.h>#include <WinSock2.h>#pragma comment(lib, "ws2_32.lib")BOOL GetHostByName(char * HostName){ WSADATA wsaData; if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) return FALSE; struct hostent *ptr = gethostbyname(HostName); if (!ptr){ return FALSE; } printf("地址类型: %s \n", (ptr->h_addrtype == AF_INET) ? "IPV4" : "IPV6"); for (int i = 0; ptr->h_aliases[i]; i++){ printf("别名 [%d]: %s \n", i + 1, ptr->h_aliases[i]); } for (int i = 0; ptr->h_addr_list[i]; i++){ printf("IP地址 [%d]: %s \n", i + 1, inet_ntoa(*(struct in_addr*)ptr->h_addr_list[i])); } WSACleanup(); return TRUE;}int main(int argc ,char *argv[]){ GetHostByName("ment(lib, "ws2_32.lib")char * GetLocalHostName(){ WSADATA wsaData; HOSTENT *pHost; char szHostName[256]; if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) exit(0); if (gethostname(szHostName, 256) == 0) { char *Host; Host = (char *)malloc(1024); pHost = gethostbyname(szHostName); strcpy(Host, pHost->h_name); return Host; } return "";}char * GetLocalHostAddr(int Count){ WSADATA wsaData; HOSTENT *pHost; char szHostName[256]; if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) exit(0); if (gethostname(szHostName, 256) == 0) { char tmp[15]; char *Addr; pHost = gethostbyname(szHostName); int index = 0; for (; index < 10; index++) { if (pHost->h_addr_list[index] == NULL) break; } sprintf(tmp, "%d.%d.%d.%d", pHost->h_addr_list[0][0] & 0xff, pHost->h_addr_list[0][1] & 0xff, pHost->h_addr_list[0][2] & 0xff, pHost->h_addr_list[0][3] & 0xff); Addr = (char *)malloc(15); strcpy(Addr, tmp); return Addr; } return "";}int main(int argc, char *argv[]){ char *hostname = GetLocalHostName(); printf("本机名字: %s \n", hostname); char *hostaddr = GetLocalHostAddr(0); printf("本机IP: %s \n", hostaddr); system("pause"); return 0;}以上就是C/C++ 获取自身IP与域名片段的示例代码的详细内容,更多关于C/C++ 获取自身IP与域名片段的资料请关注其它相关文章!