helloworld_emcc.log

$emacs main.c
$emcc main.c

include<stdio.h>
int main() {
  printf("Hello World!!");
  return 0;
}


$emcc main.c
$ls
a.out.js main.c

$ node a.out.js 
stdio streams had content in them that was not flushed. 
you should set NO_EXIT_RUNTIME to 0 (see the FAQ), or make 
sure to emit a newline when you printf etc.

$ emcc main.c -s NO_EXIT_RUNTIME=0
$ node a.out.js
Hello World!!