/* 	File: popenDemo.cpp
 *      Demo of automated pipe open function
 *	Creates pipe, forks a child, closes unused ends, 
 *	  execs a shell to execute the command, and waits for it to terminate
 */
#include 	<stdio.h>
#include	<sys/types.h>
#include	<sys/msg.h>
#include	<sys/ipc.h>
#include	<unistd.h>
#include	<stdlib.h>
#include	<limits.h>
#define MAX	5
int main(void){
  FILE	*fin;
  char	buffer[PIPE_BUF];
  int	n;
  fin = popen("ls -l", "r");   /* run the ipcs command*/
  while((n=read(fileno(fin), buffer, PIPE_BUF)) > 0)
    write(fileno(stdout), buffer, n);   /* display ipcs output */
  pclose(fin);

  exit(0);
}