// Copyright (c) 1999-2000 David Muse
// See the COPYING file for more information.


#include <sys/types.h>
#include <rudiments/signalclasses.h>

// Daemons are long running processes which often detach themselves from
// the controlling terminal and run in the background.  They are frequently
// started at boot time and run until the machine is shut down.
// Daemons typically perform "housecleaning" tasks or serve data to client
// programs.  See the server class.

class daemonprocess {
                        virtual ~daemonprocess();

                        int     checkForPidFile(char *filename);
                                // Checks for filename "filename" and reads the
                                // process id out of it, if it exists.  Returns
                                // the process id on success or 0 on failure.
                        void    createPidFile(char *filename);
                                // Create's file "filename" and puts the current
                                // process id in it.  Note that when you delete
                                // this file during shutdown you must use the 
                                // full pathname since the detach() method 
                                // below changes directories to "/".

                        void    detach();
                                // Detach from the controlling terminal and
                                // process and run in the background.  Also
                                // change directories to "/" and set the file
                                // creation mask such that all files are 
                                // created -rw-rw-rw and all directories 
                                // drwxrwxrwx.

                        // These methods allow the daemon to run as a different
                        // user or group than the one that started the process.
                        // They have no effect unless the process is started
                        // by the root user.
                        int     runAsUser(char *username);
                        int     runAsGroup(char *groupname);
                        int     runAsUserId(uid_t uid);
                        int     runAsGroupId(gid_t gid);

                static  void    handleShutDown(void *shutdownfunction);
                                // This method allows you to designate a
                                // function to run when the daemon is killed.

                #include <rudiments/private/daemonprocess.h>