/***********************************************************************
* Code listing from "Advanced Linux Programming," by CodeSourcery LLC  *
* Copyright (C) 2001 by New Riders Publishing                          *
* See COPYRIGHT for license information.                               *
***********************************************************************/

#include 
#include 
#include 
#include 

sig_atomic_t child_exit_status;

void clean_up_child_process (int signal_number)
{
  /* Clean up the child process.  */
  int status;
  wait (&status);
  /* Store its exit status in a global variable.  */
  child_exit_status = status;
}

int main ()
{
  /* Handle SIGCHLD by calling clean_up_child_process.  */
  struct sigaction sigchld_action;
  memset (&sigchld_action, 0, sizeof (sigchld_action));
  sigchld_action.sa_handler = &clean_up_child_process;
  sigaction (SIGCHLD, &sigchld_action, NULL);

  /* Now do things, including forking a child process.  */
  /* ...  */

  return 0;
}