How to deactivate input statement after some time?

Question

We know input function or operator (cin, scanf,gets….etc) wait to take input form user & this time has no limit.

Now, I will ask a question & user give the a

Answer 1

#include 
#include 
#include 
#include 

bool get_input ( char *buffer, std::size_t size, int timeout )
{
     std::time_t start = std::time ( 0 );
     std::size_t n = 0;

   for ( ; ; ) {
    if ( n == 0 && std::difftime ( std::time ( 0 ), start ) >= timeout )
     return false;

    if ( kbhit() ) {
  if ( n == size - 1 )
    break;

  char ch = (int)getche();

  if ( ch == '\r' ) {
    buffer[n++] = '\n';
    break;
  }
  else
    buffer[n++] = ch;
  }
}

 buffer[n] = '\0';

return true;
}

 int main()
{
char buffer[512] = {0};

if ( !get_input ( buffer, 512, 5 ) ) {
std::cout<<"Input timed out\n";
buffer[0] = '\n';
}

std::cout<<"input: \""<< buffer <<"\"\n";
}