Compare Dates - Times

char s[15];
sprintf(s, "%04d%02d%02d%02d%02d%02d", year, month, day, hour, minute, second);

s is my string ok, what is this "%04d%02d%02d%02d%02d%02d"? for example %04 Means take 4 digits from year ? and "%02d" take 2 digits ?

after that I will a date store like this:

20130206065244

But now this, is string of character ... i need to compare with another string ... and then should match exactly the time now ... so I need to do some "string compare" ?

and if for example in that time the cpu was doing something else ? So I want to be sure that the cpu at right time will do the operations ...

make sense for you ? Otherwise I can use Alarm.TriggerOnce() with variable,

thanks
gnux