How to make an alarm clock!?

[unixbased]

Okay so I figured out how to get time in c++ but after that I dont know how to countdown to the desired time that the user set and maybe say "the alarm has gone off" ..I dont know where to go from here:

#include <iostream>
#include <ctime>
#include <iomanip>

using namespace std;

char dateStr [9];
char timeStr [9];
char almtimestr[9];

int main(){

_strtime( timeStr);
_strtime( almtimestr);

int consoleWidth=70;
cout<<setw(consoleWidth / 2)<<" "<<"The current time is: "<<timeStr<<endl;
cout<<setw(consoleWidth / 2)<<" "<<endl;
cout<<setw(consoleWidth / 2)<<" "<<"Pls format time as utc"<<endl;
cin >> almtimestr;
//after this I have no idea how to countdown to the desired time say 3:00 pm!!
}

How to check if the time is up or do I count down I have no clue!!
I just needed some instructions and Imma right but can someone pls give me an example of this timing thing !! PLSS I am desperate right now and this is due for tomorow!

[TheDestroyer]

You don't have to count down. Just check the time every minute, if the hours and minutes are equal to the alarm time, start the event of the alarm.

[unixbased]

how do I check I dont understand??

[unixbased]

is like an if or while statement or something to check SOMEONE HELP!!

[TheDestroyer]

There are sleep functions available everywhere. Find one, and make your program sleep for a minute. You may use a while loop, but that's bad because it keeps your processor busy all the time.

Find a sleep function, that'll do it.