#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <error.h>

#include <errno.h>

#include <sys/wait.h>

void __attribute_noinline__ noop (void);

#define NR	2	/* Exit code of the child.  */

int

main (void)

{

  pid_t pid;

  int status;

  printf ("Before vfork\n");

  fflush (stdout);

  pid = vfork ();

  if (pid == 0)

    {

      /* This will clobber the return pc from vfork in the parent on

	 machines where it is stored on the stack, if vfork wasn't

	 implemented correctly, */

      noop ();

      _exit (NR);

    }

  else if (pid < 0)

    error (1, errno, "vfork");

  printf ("After vfork (parent)\n");

  if (waitpid (0, &status, 0) != pid

      || !WIFEXITED (status) || WEXITSTATUS (status) != NR)

    exit (1);

  return 0;

}

void

noop (void)

{

}