#include	<signal.h>
#include <stdio.h>
#include <unistd.h> /* por write*/ 
/*#include	"ourhdr.h"*/

static void	sig_alrm(int);

#define MAXLINE 200

void  err_sys(char * msg) {
  printf("%s \n", msg);
  exit(-1); 
}

int main(void)
{
	int		n;
	char	line[MAXLINE];

	if (signal(SIGALRM, sig_alrm) == SIG_ERR)
		err_sys("signal(SIGALRM) error");
	alarm(10);
	/* 1. There is a race condition here. Think of having this process
		blocked for more than 10 seconds.
	2. If the system call (read) is restarted automatically, 
		the time out does nothing! */
	if ( (n = read(STDIN_FILENO, line, MAXLINE)) < 0)
		err_sys("read error");
	alarm(0);

	write(STDOUT_FILENO, line, n);

	exit(0);
}

static void sig_alrm(int signo)
{
	return;	/* nothing to do, just return to interrupt the read */
}