Atomic writeStateToFile

liskin · Dec 17, 2023 · cc6c9f5 · cc6c9f5
1 parent 86a5761
commit cc6c9f5
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/src/XMonad/Operations.hs b/src/XMonad/Operations.hs
@@ -79,6 +79,7 @@ import qualified Control.Exception as C
 
 import System.IO
 import System.Directory
+import System.FilePath ((<.>))
 import System.Posix.Process (executeFile)
 import Graphics.X11.Xlib
 import Graphics.X11.Xinerama (getScreenInfo)
@@ -663,7 +664,9 @@ writeStateToFile = do
     globalPath <- asks $ stateFileName . directories
     path <- fromMaybe globalPath <$> sessionStateFileName
     stateData <- gets (\s -> StateFile (wsData s) (extState s))
-    catchIO (writeFile path $ show stateData)
+    catchIO $ do
+        writeFile (path <.> "tmp") $ show stateData
+        renameFile (path <.> "tmp") path
 
 -- | Read the state of a previous xmonad instance from a file and
 -- return that state.  The state file is removed after reading it.