-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Systemd facilities (Socket activation, Notify)
--   
--   A module for Systemd facilities.
@package systemd
@version 1.1.0


-- | Implementation of Systemd facilities to create and manage daemons.
--   
--   This module contains socket activation and notify tools. See
--   
--   <ul>
--   
--   <li><a>http://0pointer.de/blog/projects/socket-activation.html</a></li>
--   
--   <li><a>http://www.freedesktop.org/software/systemd/man/systemd.socket.html</a></li>
--   
--   <li><a>http://www.freedesktop.org/software/systemd/man/systemd.service.html</a></li>
--   </ul>
--   
--   Example:
--   
--   <pre>
--   import Control.Monad(forever)
--   import System.Systemd.Daemon(notifyWatchdog)
--   
--   main :: IO ()
--   main = forever $ do
--           functionThatMayHang
--           notifyWatchdog
--   </pre>
--   
--   If you use the service described as below, Systemd will restart your
--   program each time the watchdog fail to notify itself under 60 sec.
--   
--   <pre>
--   [Unit]
--   Description=MyDaemon
--   
--   [Service]
--   Type=simple
--   TimeoutStartSec=0
--   ExecStart=AbsolutePathToMyExecutable
--   WatchdogSec=60
--   Restart=on-failure
--   
--   [Install]
--   WantedBy=multi-user.target
--   </pre>
module System.Systemd.Daemon

-- | Notify systemd about an event After notifying systemd the <a>Bool</a>
--   parameter specify if the environnement shall be unset (Further call to
--   notify will fail) The <tt>String</tt> is the event to pass Returns
--   <tt>Nothing</tt> if the program was not started with systemd or that
--   the environnement was previously unset
notify :: Bool -> String -> IO (Maybe ())

-- | Same as <tt>notify</tt> but send a long a socket to be stored It is up
--   to the caller to properly set the message (i.e: do not forget to set
--   FDSTORE=1)
notifyWithFD :: Bool -> String -> Socket -> IO (Maybe ())

-- | Notify systemd to store a socket for us To be used along
--   getActivatedSockets during a restart usefull for zero downtime restart
storeFd :: Bool -> Socket -> IO (Maybe ())

-- | Notify systemd to store a socket for us and specify a name To be used
--   along getActivatedSocketsWithNames during a restart usefull for zero
--   downtime restart
storeFdWithName :: Bool -> Socket -> String -> IO (Maybe ())

-- | Notify the watchdog that the program is still alive
notifyWatchdog :: IO (Maybe ())

-- | Notify the systemd that the program is ready
notifyReady :: IO (Maybe ())

-- | Notify systemd of the PID of the program (for after a fork)
notifyPID :: CPid -> IO (Maybe ())

-- | Notify systemd of an <a>Errno</a> error
notifyErrno :: Errno -> IO (Maybe ())

-- | Notify systemd of the status of the program. An arbitrary
--   <a>String</a> can be passed
notifyStatus :: String -> IO (Maybe ())

-- | Notify systemd of a DBUS error like. Correct formatting of the
--   <a>String</a> is left to the caller
notifyBusError :: String -> IO (Maybe ())

-- | Notify systemd that the service is reloading its configuration
notifyReloading :: IO (Maybe ())

-- | Notify systemd that the service is beginning its shutdown
notifyStopping :: IO (Maybe ())

-- | Return a list of activated sockets, if the program was started with
--   socket activation. The sockets are in the same order as in the
--   associated <tt>.socket</tt> file. The sockets will have their family,
--   type, and status set appropriately. Returns <tt>Nothing</tt> in
--   systems without socket activation (or when the program was not socket
--   activated).
getActivatedSockets :: IO (Maybe [Socket])

-- | Same as <tt>getActivatedSockets</tt> but return also the name
--   associated with those sockets if <tt>storeFdWithName</tt> was used. IF
--   <tt>storeFd</tt> was used to transmit the socket to systemd, the name
--   will be a generic one (i.e: usally "stored")
getActivatedSocketsWithNames :: IO (Maybe [(Socket, String)])

-- | Unset all environnement variable related to Systemd. Calls to
--   <a>notify</a> like and <a>getActivatedSockets</a> functions will
--   return <a>Nothing</a> after that
unsetEnvironnement :: IO ()