different within getchar(); and while (getchar() != '\n') ;

[Icenel]

Different between this
Why we should replace
getchar();

with
while (getchar() != '\n') ;

please let me know their meaning

Thank you

[ne555]

For what purpose?
getchar returns a character from the standard input.

[wolfgang]

I'm guessing that that line is at the end of a program?

As I can test there is no difference between the two lines as both wait for '\n' to get input (that's the user hitting enter.) If you change the '\n' to something like '9' or ';' you can keep it open until you get that specific character.

#include <cstdio> // for getchar();
#include <iostream>

using namespace std;

int main()
{
  cout << "Closing!" << endl;

  getchar(); // Waits for '\n' (user hitting enter)
  while(getchar() != '\n'); // Waits for '\n'
  while(getchar() != '9'); // Waits for user to enter '9' and enter.

  return 0;
}

Reference on getchar(): http://www.cplusplus.com/reference/clibrary/cstdio/getchar/