The Win32-services package
This package provides a partial binding to the Win32 System Services API. It makes it easy to write Windows service applications using Haskell.
The binding is partial. Here are a few ways in which it differs from the official API:
Only services running within their own process are supported. These are processes of the WIN32_OWN_PROCESS type.
In cases where multiple versions of the same function exist (for compatibility), this binding only offers one of them.
None of the extended control codes are supported. Handlers you write will automatically report this to the operating system when such controls are received.
Only facilities for writing services are supported; not controlling them.
Effort has been made to simplify using the API without hiding what is happening behind the scenes. Users are encouraged to read Microsoft's documentation under 'Dev Center - Desktop > Docs > Desktop app development documentation > System Services > Services'. The official example has been ported to Haskell. This can be found in the examples directory of the source tree.
Simple Example and Usage
module Main where import Control.Concurrent.MVar import System.Win32.SystemServices.Services main = do mStop <- newEmptyMVar startServiceCtrlDispatcher "Test" 3000 (handler mStop) $ \_ _ h -> do setServiceStatus h running takeMVar mStop setServiceStatus h stopped handler mStop hStatus STOP = do setServiceStatus hStatus stopPending putMVar mStop () return True handler _ _ INTERROGATE = return True handler _ _ _ = return False running = SERVICE_STATUS WIN32_OWN_PROCESS RUNNING [ACCEPT_STOP] nO_ERROR 0 0 0 stopped = SERVICE_STATUS WIN32_OWN_PROCESS STOPPED  nO_ERROR 0 0 0 stopPending = SERVICE_STATUS WIN32_OWN_PROCESS START_PENDING [ACCEPT_STOP] nO_ERROR 0 0 0
C:programmingtest>ghc --make -threaded Main.hs [1 of 1] Compiling Main ( Main.hs, Main.o ) Linking Main.exe ... <linker warnings omitted> C:\programming\test>copy Main.exe c:\svc\Test.exe 1 file(s) copied.
Execute the following from an elevated command prompt to register the service:
C:\svc>sc create Test binPath= c:\svc\Test.exe [SC] CreateService SUCCESS
The service can now be started and stopped from the services console.
Depending on which version of Windows and the Windows SDK you are using the .cabal file will need to be modified before installing. A simple `cabal install Win32-services` may not work. For example, If you are building on Windows 8 64-bit with the Windows 8 SDK the extra-lib-dirs field will need to be changed to read as follows:
Extra-Lib-Dirs: "C:\\Program Files (x86)\\Windows Kits\\8.0\\Lib\\win8\\um\\x86"
Changes in 0.2.1
bug fix: Services were failing to enter a STOPPED state. It is now the user's responsibility to enter a stopped state in the service main function. The startServiceCtrlDispatcher function will continue to automatically put the service into a START_PENDING state.
Changes in 0.2
Writing services of the WIN32_OWN_PROCESS type is now easier. Handler registration is performed automatically. By the time the service main function is entered, the service will already be in the START_PENDING state. It is the user's responsibility to enter the RUNNING state as soon as possible.
Once the service main function exits two things will occur. The service will enter the STOPPED state, and the handler function will be freed.
The registerServiceCtrlHandlerEx function is no longer exported. Handlers are registered automatically by the startServiceCtrlDispatcher function.
The queryServiceStatus function has been added.
Changes in 0.1
|Versions||0.1, 0.2, 0.2.1, 0.2.2, 0.2.2.1, 0.2.3, 0.2.3.1, 0.2.4, 0.2.5, 0.2.5.1, 0.3 (info)|
|Dependencies||base (==4.5.*), errors, Win32 [details]|
|Copyright||Copyright (C) 2011-2013 Michael Steele|
|Maintainer||Michael Steele <firstname.lastname@example.org>|
|Source repository||head: git clone git://github.com/mikesteele81/win32-services.git|
|Uploaded||Sun Apr 7 21:33:47 UTC 2013 by MichaelSteele|
|Downloads||2266 total (41 in the last 30 days)|
|Status||Docs not available [build log]
All reported builds failed as of 2015-12-08 [all 5 reports]
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