Put function into while loop condition statement : While Loop « Statement « C Tutorial

1. C Tutorial
2. Statement
3. While Loop

#include <stdio.h>
 
int main()
{
    puts("Start typing.");
    puts("Press ~ then Enter to stop");
 
    while(getchar() != '~')
        ;
    printf("Thanks!\n");
    return(0);
}

Start typing.
      Press ~ then Enter to stop
      a
      a
      a
      a
      a
      a~
      Thanks!