line2dots

Reads from stdin and puts to stdout a dot (.) each time it reads a newline.

#include <stdio.h>
#include <stdlib.h>

void putdot(){
  putchar('.');
  fflush(stdout);
}

int main (int argc, char** argv) {
  while(1) {
    switch (getchar()) {
    case '\n':
      putdot();
      switch (getchar()) {
      case '\n':
        putdot();
        break;
      default:
        break;
      }
      break;
    case '\r':
      putdot();
      switch (getchar()) {
      case '\r':
        putdot();
        break;
      default:
        break;
      }
      break;
    case EOF:
      putchar('\n');
      return 0;
    default:
      break;
    }
  }
}

/* end of line2dots.c                                              */

It is equivalent to

#!/bin/sh
while read ; do echo -n '.' ; done ; echo