Code:
#include <time.h>

int main(int argc, char *argv[])                                     
{                                          
   time_t lt;                              
   struct tm t, *tmptr;                    
   char tmp[26]={'\0'};                                         
   lt=time(NULL);                          
   tmptr=localtime( & lt );                
   strcpy(tmp,asctime(tmptr));                   
   printf("%s\n",asctime(tmptr));
   printf("%s\n",tmp);
   return 0;                               
}
asctime() returns a static char *, which will change with subsequent calls to time functions; this makes a local copy.