Shell Programming and Scripting

#include <time.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char *argv[]) {
   long long adj = 0;
   char res[1024], fmt[1024] = "%d/%b/%Y %T";
   time_t secs_now;
   struct tm *time_now = (struct tm *)malloc(sizeof(struct tm));
   if (argc > 1) adj=atoll(argv[argc-1]);
   if (argc > 2) strcpy(fmt, argv[1]);
   if (argc > 1 && *argv[argc-1] == '@') secs_now=atoll(argv[argc-1]+1);
   else secs_now = time(NULL)+adj;
   *time_now = *localtime(&secs_now);
   strftime(res, 1024, fmt, time_now);
   free(time_now);
   puts(res);
   return 0;
}

$ ./dateadj
21/Jan/2011 08:15:22
$ ./dateadj -60
21/Jan/2011 08:14:26
$ ./dateadj '%H%M' -60
0814
$ ./dateadj @1294581600 
10/Jan/2011 00:00:00

timetmp=$(perl -e 'print scalar(localtime(time()-60))'|awk '{printf $4}' |awk -F":" '{printf $2}')