kbhit in c

kbhit in c: kbhit function is used to determine if a key has been pressed or not. To use kbhit function in your program you should include the header file "conio.h". If a key has been pressed then it returns a non zero value otherwise returns zero.
Declaration : int kbhit();

C programming code for kbhit

#include <stdio.h>
#include <conio.h>
 
main()
{
   while (!kbhit())
      printf("You haven't pressed a key.\n");
 
   return 0;
}

As long as in the above program user doesn't presses a key kbhit() return zero and (!0) i.e. 1 the condition in while loop is true and "You haven't pressed a key." will be printed again and again. As a key is pressed from the keyboard the condition in while loop become false as now kbhit() will return a non-zero value and ( !(non-zero) = 0), so the control will come out of the while loop.