函数名: asctime 
 功  能: 转换日期和时间为ASCII码 
 用  法: #include <time.h>
         char *asctime(const struct tm *tblock); 
 程序例: 
 #include <stdio.h> 
 #include <string.h> 
 #include <time.h> 
int main(void) 
 { 
    struct tm t; 
    char str[80]; 
/* sample loading of tm structure */
   t.tm_sec    = 1;  /* Seconds */ 
    t.tm_min    = 30; /* Minutes */ 
    t.tm_hour   = 9;  /* Hour */ 
    t.tm_mday   = 22; /* Day of the Month  */ 
    t.tm_mon    = 11; /* Month */ 
    t.tm_year   = 56; /* Year - does not include century */ 
    t.tm_wday   = 4;  /* Day of the week  */ 
    t.tm_yday   = 0;  /* Does not show in asctime  */ 
    t.tm_isdst  = 0;  /* Is Daylight SavTime; does not show in asctime */ 
   /* converts structure to null terminated 
    string */ 
   strcpy(str, asctime(&t)); 
    printf("%s\n", str); 
   return 0; 
 }