純C/C++ mktime()函數

資料來源: http://www.w3big.com/zh-TW/cplusplus/c-function-mktime.html

線上編譯器: https://www.tutorialspoint.com/compile_c_online.php

time_t mktime(struct tm *timeptr)函數，把timeptr所指向的結構轉換為一個依據本地時區的time_t值

code:

#include <stdio.h>
#include <time.h>

#define BST (+1)
#define CCT (+8)

int main ()
{

   time_t rawtime;
   struct tm *info;
   int ret;
   char buffer[80];

   time(&rawtime);
   /* 获取 GMT 时间 */
   info = gmtime(&rawtime );

   ret = mktime(info);
   if( ret == -1 )
   {
       printf("错误：不能使用 mktime 转换时间。\n");
   }
   else
   {
      strftime(buffer, sizeof(buffer), "%c", info );
      printf(buffer);
   }   
   
   printf("当前的世界时钟：\n");
   printf("伦敦：%2d:%02d\n", (info->tm_hour+BST)%24, info->tm_min);
   printf("中国：%2d:%02d\n", (info->tm_hour+CCT)%24, info->tm_min);

   return(0);
}