{-# LANGUAGE ForeignFunctionInterface, NondecreasingIndentation #-} ----------------------------------------------------------------------------- -- | -- Module : System.Directory -- Copyright : (c) The University of Glasgow 2001 -- License : BSD-style (see the file libraries/base/LICENSE) -- -- Maintainer : libraries@haskell.org -- Stability : stable -- Portability : portable -- -- System-independent interface to directory manipulation. -- ----------------------------------------------------------------------------- module System.Directory ( -- $intro -- * Actions on directories createDirectory -- :: FilePath -> IO () , createDirectoryIfMissing -- :: Bool -> FilePath -> IO () , removeDirectory -- :: FilePath -> IO () , removeDirectoryRecursive -- :: FilePath -> IO () , renameDirectory -- :: FilePath -> FilePath -> IO () , getDirectoryContents -- :: FilePath -> IO [FilePath] , getCurrentDirectory -- :: IO FilePath , setCurrentDirectory -- :: FilePath -> IO () -- * Pre-defined directories , getHomeDirectory , getAppUserDataDirectory , getUserDocumentsDirectory , getTemporaryDirectory -- * Actions on files , removeFile -- :: FilePath -> IO () , renameFile -- :: FilePath -> FilePath -> IO () , copyFile -- :: FilePath -> FilePath -> IO () , canonicalizePath , makeRelativeToCurrentDirectory , findExecutable -- * Existence tests , doesFileExist -- :: FilePath -> IO Bool , doesDirectoryExist -- :: FilePath -> IO Bool -- * Permissions -- $permissions , Permissions( Permissions, readable, -- :: Permissions -> Bool writable, -- :: Permissions -> Bool executable, -- :: Permissions -> Bool searchable -- :: Permissions -> Bool ) , getPermissions -- :: FilePath -> IO Permissions , setPermissions -- :: FilePath -> Permissions -> IO () , copyPermissions -- * Timestamps , getModificationTime -- :: FilePath -> IO ClockTime ) where import Prelude hiding ( catch ) import qualified Prelude import Control.Monad (guard) import System.Environment ( getEnv ) import System.FilePath import System.IO import System.IO.Error hiding ( catch, try ) import Control.Monad ( when, unless ) import Control.Exception.Base import Foreign import Foreign.C {-# CFILES cbits/directory.c #-} import System.Time ( ClockTime(..) ) import GHC.IO.Exception ( IOException(..), IOErrorType(..), ioException ) import System.Posix.Types import System.Posix.Internals import qualified System.Win32 as Win32 {- $intro A directory contains a series of entries, each of which is a named reference to a file system object (file, directory etc.). Some entries may be hidden, inaccessible, or have some administrative function (e.g. `.' or `..' under POSIX ), but in this standard all such entries are considered to form part of the directory contents. Entries in sub-directories are not, however, considered to form part of the directory contents. Each file system object is referenced by a /path/. There is normally at least one absolute path to each file system object. In some operating systems, it may also be possible to have paths which are relative to the current directory. -} ----------------------------------------------------------------------------- -- Permissions {- $permissions The 'Permissions' type is used to record whether certain operations are permissible on a file\/directory. 'getPermissions' and 'setPermissions' get and set these permissions, respectively. Permissions apply both to files and directories. For directories, the executable field will be 'False', and for files the searchable field will be 'False'. Note that directories may be searchable without being readable, if permission has been given to use them as part of a path, but not to examine the directory contents. Note that to change some, but not all permissions, a construct on the following lines must be used. > makeReadable f = do > p <- getPermissions f > setPermissions f (p {readable = True}) -} data Permissions = Permissions { readable, writable, executable, searchable :: Bool } deriving (Eq, Ord, Read, Show) {- |The 'getPermissions' operation returns the permissions for the file or directory. The operation may fail with: * 'isPermissionError' if the user is not permitted to access the permissions; or * 'isDoesNotExistError' if the file or directory does not exist. -} getPermissions :: FilePath -> IO Permissions getPermissions name = do withFilePath name $ \s -> do -- stat() does a better job of guessing the permissions on Windows -- than access() does. e.g. for execute permission, it looks at the -- filename extension :-) -- -- I tried for a while to do this properly, using the Windows security API, -- and eventually gave up. getPermissions is a flawed API anyway. -- SimonM allocaBytes sizeof_stat $ \ p_stat -> do throwErrnoIfMinus1_ "getPermissions" $ c_stat s p_stat mode <- st_mode p_stat let usr_read = mode .&. s_IRUSR let usr_write = mode .&. s_IWUSR let usr_exec = mode .&. s_IXUSR let is_dir = mode .&. s_IFDIR return ( Permissions { readable = usr_read /= 0, writable = usr_write /= 0, executable = is_dir == 0 && usr_exec /= 0, searchable = is_dir /= 0 && usr_exec /= 0 } ) {- |The 'setPermissions' operation sets the permissions for the file or directory. The operation may fail with: * 'isPermissionError' if the user is not permitted to set the permissions; or * 'isDoesNotExistError' if the file or directory does not exist. -} setPermissions :: FilePath -> Permissions -> IO () setPermissions name (Permissions r w e s) = do allocaBytes sizeof_stat $ \ p_stat -> do withFilePath name $ \p_name -> do throwErrnoIfMinus1_ "setPermissions" $ do c_stat p_name p_stat mode <- st_mode p_stat let mode1 = modifyBit r mode s_IRUSR let mode2 = modifyBit w mode1 s_IWUSR let mode3 = modifyBit (e || s) mode2 s_IXUSR c_wchmod p_name mode3 where modifyBit :: Bool -> CMode -> CMode -> CMode modifyBit False m b = m .&. (complement b) modifyBit True m b = m .|. b foreign import ccall unsafe "_wchmod" c_wchmod :: CWString -> CMode -> IO CInt copyPermissions :: FilePath -> FilePath -> IO () copyPermissions source dest = do allocaBytes sizeof_stat $ \ p_stat -> do withFilePath source $ \p_source -> do withFilePath dest $ \p_dest -> do throwErrnoIfMinus1_ "copyPermissions" $ c_stat p_source p_stat mode <- st_mode p_stat throwErrnoIfMinus1_ "copyPermissions" $ c_wchmod p_dest mode ----------------------------------------------------------------------------- -- Implementation {- |@'createDirectory' dir@ creates a new directory @dir@ which is initially empty, or as near to empty as the operating system allows. The operation may fail with: * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES]@ * 'isAlreadyExistsError' \/ 'AlreadyExists' The operand refers to a directory that already exists. @ [EEXIST]@ * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'NoSuchThing' There is no path to the directory. @[ENOENT, ENOTDIR]@ * 'ResourceExhausted' Insufficient resources (virtual memory, process file descriptors, physical disk space, etc.) are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'InappropriateType' The path refers to an existing non-directory object. @[EEXIST]@ -} createDirectory :: FilePath -> IO () createDirectory path = do Win32.createDirectory path Nothing -- | @'createDirectoryIfMissing' parents dir@ creates a new directory -- @dir@ if it doesn\'t exist. If the first argument is 'True' -- the function will also create all parent directories if they are missing. createDirectoryIfMissing :: Bool -- ^ Create its parents too? -> FilePath -- ^ The path to the directory you want to make -> IO () createDirectoryIfMissing create_parents path0 | create_parents = createDirs (parents path0) | otherwise = createDirs (take 1 (parents path0)) where parents = reverse . scanl1 () . splitDirectories . normalise createDirs [] = return () createDirs (dir:[]) = createDir dir throw createDirs (dir:dirs) = createDir dir $ \_ -> do createDirs dirs createDir dir throw createDir :: FilePath -> (IOException -> IO ()) -> IO () createDir dir notExistHandler = do r <- try $ createDirectory dir case (r :: Either IOException ()) of Right () -> return () Left e | isDoesNotExistError e -> notExistHandler e -- createDirectory (and indeed POSIX mkdir) does not distinguish -- between a dir already existing and a file already existing. So we -- check for it here. Unfortunately there is a slight race condition -- here, but we think it is benign. It could report an exeption in -- the case that the dir did exist but another process deletes the -- directory and creates a file in its place before we can check -- that the directory did indeed exist. | isAlreadyExistsError e -> (do withFileStatus "createDirectoryIfMissing" dir $ \st -> do isDir <- isDirectory st if isDir then return () else throw e ) `catch` ((\_ -> return ()) :: IOException -> IO ()) | otherwise -> throw e {- | @'removeDirectory' dir@ removes an existing directory /dir/. The implementation may specify additional constraints which must be satisfied before a directory can be removed (e.g. the directory has to be empty, or may not be in use by other processes). It is not legal for an implementation to partially remove a directory unless the entire directory is removed. A conformant implementation need not support directory removal in all situations (e.g. removal of the root directory). The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. EIO * 'InvalidArgument' The operand is not a valid directory name. [ENAMETOOLONG, ELOOP] * 'isDoesNotExistError' \/ 'NoSuchThing' The directory does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY, ENOTEMPTY, EEXIST]@ * 'UnsupportedOperation' The implementation does not support removal in this situation. @[EINVAL]@ * 'InappropriateType' The operand refers to an existing non-directory object. @[ENOTDIR]@ -} removeDirectory :: FilePath -> IO () removeDirectory path = Win32.removeDirectory path -- | @'removeDirectoryRecursive' dir@ removes an existing directory /dir/ -- together with its content and all subdirectories. Be careful, -- if the directory contains symlinks, the function will follow them. removeDirectoryRecursive :: FilePath -> IO () removeDirectoryRecursive startLoc = do cont <- getDirectoryContents startLoc sequence_ [rm (startLoc x) | x <- cont, x /= "." && x /= ".."] removeDirectory startLoc where rm :: FilePath -> IO () rm f = do temp <- try (removeFile f) case temp of Left e -> do isDir <- doesDirectoryExist f -- If f is not a directory, re-throw the error unless isDir $ throw (e :: SomeException) removeDirectoryRecursive f Right _ -> return () {- |'removeFile' /file/ removes the directory entry for an existing file /file/, where /file/ is not itself a directory. The implementation may specify additional constraints which must be satisfied before a file can be removed (e.g. the file may not be in use by other processes). The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid file name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The file does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY]@ * 'InappropriateType' The operand refers to an existing directory. @[EPERM, EINVAL]@ -} removeFile :: FilePath -> IO () removeFile path = Win32.deleteFile path {- |@'renameDirectory' old new@ changes the name of an existing directory from /old/ to /new/. If the /new/ directory already exists, it is atomically replaced by the /old/ directory. If the /new/ directory is neither the /old/ directory nor an alias of the /old/ directory, it is removed as if by 'removeDirectory'. A conformant implementation need not support renaming directories in all situations (e.g. renaming to an existing directory, or across different physical devices), but the constraints must be documented. On Win32 platforms, @renameDirectory@ fails if the /new/ directory already exists. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' Either operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The original directory does not exist, or there is no path to the target. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY, ENOTEMPTY, EEXIST]@ * 'UnsupportedOperation' The implementation does not support renaming in this situation. @[EINVAL, EXDEV]@ * 'InappropriateType' Either path refers to an existing non-directory object. @[ENOTDIR, EISDIR]@ -} renameDirectory :: FilePath -> FilePath -> IO () renameDirectory opath npath = do -- XXX this test isn't performed atomically with the following rename -- ToDo: use Win32 API withFileStatus "renameDirectory" opath $ \st -> do is_dir <- isDirectory st if (not is_dir) then ioException (ioeSetErrorString (mkIOError InappropriateType "renameDirectory" Nothing (Just opath)) "not a directory") else do Win32.moveFileEx opath npath Win32.mOVEFILE_REPLACE_EXISTING {- |@'renameFile' old new@ changes the name of an existing file system object from /old/ to /new/. If the /new/ object already exists, it is atomically replaced by the /old/ object. Neither path may refer to an existing directory. A conformant implementation need not support renaming files in all situations (e.g. renaming across different physical devices), but the constraints must be documented. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' Either operand is not a valid file name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The original file does not exist, or there is no path to the target. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EROFS, EACCES, EPERM]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. @[EDQUOT, ENOSPC, ENOMEM, EMLINK]@ * 'UnsatisfiedConstraints' Implementation-dependent constraints are not satisfied. @[EBUSY]@ * 'UnsupportedOperation' The implementation does not support renaming in this situation. @[EXDEV]@ * 'InappropriateType' Either path refers to an existing directory. @[ENOTDIR, EISDIR, EINVAL, EEXIST, ENOTEMPTY]@ -} renameFile :: FilePath -> FilePath -> IO () renameFile opath npath = do -- XXX this test isn't performed atomically with the following rename -- ToDo: use Win32 API withFileOrSymlinkStatus "renameFile" opath $ \st -> do is_dir <- isDirectory st if is_dir then ioException (ioeSetErrorString (mkIOError InappropriateType "renameFile" Nothing (Just opath)) "is a directory") else do Win32.moveFileEx opath npath Win32.mOVEFILE_REPLACE_EXISTING {- |@'copyFile' old new@ copies the existing file from /old/ to /new/. If the /new/ file already exists, it is atomically replaced by the /old/ file. Neither path may refer to an existing directory. The permissions of /old/ are copied to /new/, if possible. -} copyFile :: FilePath -> FilePath -> IO () copyFile fromFPath toFPath = copy `Prelude.catch` (\exc -> throw $ ioeSetLocation exc "copyFile") where copy = bracket (openBinaryFile fromFPath ReadMode) hClose $ \hFrom -> bracketOnError openTmp cleanTmp $ \(tmpFPath, hTmp) -> do allocaBytes bufferSize $ copyContents hFrom hTmp hClose hTmp ignoreIOExceptions $ copyPermissions fromFPath tmpFPath renameFile tmpFPath toFPath openTmp = openBinaryTempFile (takeDirectory toFPath) ".copyFile.tmp" cleanTmp (tmpFPath, hTmp) = do ignoreIOExceptions $ hClose hTmp ignoreIOExceptions $ removeFile tmpFPath bufferSize = 1024 copyContents hFrom hTo buffer = do count <- hGetBuf hFrom buffer bufferSize when (count > 0) $ do hPutBuf hTo buffer count copyContents hFrom hTo buffer ignoreIOExceptions io = io `catch` ioExceptionIgnorer ioExceptionIgnorer :: IOException -> IO () ioExceptionIgnorer _ = return () -- | Given path referring to a file or directory, returns a -- canonicalized path, with the intent that two paths referring -- to the same file\/directory will map to the same canonicalized -- path. Note that it is impossible to guarantee that the -- implication (same file\/dir \<=\> same canonicalizedPath) holds -- in either direction: this function can make only a best-effort -- attempt. canonicalizePath :: FilePath -> IO FilePath canonicalizePath fpath = do path <- Win32.getFullPathName fpath return (normalise path) -- normalise does more stuff, like upper-casing the drive letter -- | 'makeRelative' the current directory. makeRelativeToCurrentDirectory :: FilePath -> IO FilePath makeRelativeToCurrentDirectory x = do cur <- getCurrentDirectory return $ makeRelative cur x -- | Given an executable file name, searches for such file in the -- directories listed in system PATH. The returned value is the path -- to the found executable or Nothing if an executable with the given -- name was not found. For example (findExecutable \"ghc\") gives you -- the path to GHC. -- -- The path returned by 'findExecutable' corresponds to the -- program that would be executed by 'System.Process.createProcess' -- when passed the same string (as a RawCommand, not a ShellCommand). -- -- On Windows, 'findExecutable' calls the Win32 function 'SearchPath', -- which may search other places before checking the directories in -- @PATH@. Where it actually searches depends on registry settings, -- but notably includes the directory containing the current -- executable. See -- for more -- details. -- findExecutable :: String -> IO (Maybe FilePath) findExecutable binary = Win32.searchPath Nothing binary ('.':exeExtension) {- |@'getDirectoryContents' dir@ returns a list of /all/ entries in /dir/. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The directory does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EACCES]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. @[EMFILE, ENFILE]@ * 'InappropriateType' The path refers to an existing non-directory object. @[ENOTDIR]@ -} getDirectoryContents :: FilePath -> IO [FilePath] getDirectoryContents path = modifyIOError ((`ioeSetFileName` path) . (`ioeSetLocation` "getDirectoryContents")) $ do bracket (Win32.findFirstFile (path "*")) (\(h,_) -> Win32.findClose h) (\(h,fdat) -> loop h fdat []) where -- we needn't worry about empty directories: adirectory always -- has at least "." and ".." entries loop :: Win32.HANDLE -> Win32.FindData -> [FilePath] -> IO [FilePath] loop h fdat acc = do filename <- Win32.getFindDataFileName fdat more <- Win32.findNextFile h fdat if more then loop h fdat (filename:acc) else return (filename:acc) -- no need to reverse, ordering is undefined {- |If the operating system has a notion of current directories, 'getCurrentDirectory' returns an absolute path to the current directory of the calling process. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'isDoesNotExistError' \/ 'NoSuchThing' There is no path referring to the current directory. @[EPERM, ENOENT, ESTALE...]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EACCES]@ * 'ResourceExhausted' Insufficient resources are available to perform the operation. * 'UnsupportedOperation' The operating system has no notion of current directory. -} getCurrentDirectory :: IO FilePath getCurrentDirectory = do Win32.getCurrentDirectory {- |If the operating system has a notion of current directories, @'setCurrentDirectory' dir@ changes the current directory of the calling process to /dir/. The operation may fail with: * 'HardwareFault' A physical I\/O error has occurred. @[EIO]@ * 'InvalidArgument' The operand is not a valid directory name. @[ENAMETOOLONG, ELOOP]@ * 'isDoesNotExistError' \/ 'NoSuchThing' The directory does not exist. @[ENOENT, ENOTDIR]@ * 'isPermissionError' \/ 'PermissionDenied' The process has insufficient privileges to perform the operation. @[EACCES]@ * 'UnsupportedOperation' The operating system has no notion of current directory, or the current directory cannot be dynamically changed. * 'InappropriateType' The path refers to an existing non-directory object. @[ENOTDIR]@ -} setCurrentDirectory :: FilePath -> IO () setCurrentDirectory path = Win32.setCurrentDirectory path {- |The operation 'doesDirectoryExist' returns 'True' if the argument file exists and is a directory, and 'False' otherwise. -} doesDirectoryExist :: FilePath -> IO Bool doesDirectoryExist name = (withFileStatus "doesDirectoryExist" name $ \st -> isDirectory st) `catch` ((\ _ -> return False) :: IOException -> IO Bool) {- |The operation 'doesFileExist' returns 'True' if the argument file exists and is not a directory, and 'False' otherwise. -} doesFileExist :: FilePath -> IO Bool doesFileExist name = (withFileStatus "doesFileExist" name $ \st -> do b <- isDirectory st; return (not b)) `catch` ((\ _ -> return False) :: IOException -> IO Bool) {- |The 'getModificationTime' operation returns the clock time at which the file or directory was last modified. The operation may fail with: * 'isPermissionError' if the user is not permitted to access the modification time; or * 'isDoesNotExistError' if the file or directory does not exist. -} getModificationTime :: FilePath -> IO ClockTime getModificationTime name = do -- ToDo: use Win32 API withFileStatus "getModificationTime" name $ \ st -> do modificationTime st withFileStatus :: String -> FilePath -> (Ptr CStat -> IO a) -> IO a withFileStatus loc name f = do modifyIOError (`ioeSetFileName` name) $ allocaBytes sizeof_stat $ \p -> withFilePath (fileNameEndClean name) $ \s -> do throwErrnoIfMinus1Retry_ loc (c_stat s p) withFileOrSymlinkStatus :: String -> FilePath -> (Ptr CStat -> IO a) -> IO a withFileOrSymlinkStatus loc name f = do modifyIOError (`ioeSetFileName` name) $ allocaBytes sizeof_stat $ \p -> withFilePath name $ \s -> do throwErrnoIfMinus1Retry_ loc (lstat s p) modificationTime :: Ptr CStat -> IO ClockTime modificationTime stat = do mtime <- st_mtime stat let realToInteger = round . realToFrac :: Real a => a -> Integer return (TOD (realToInteger (mtime :: CTime)) 0) isDirectory :: Ptr CStat -> IO Bool isDirectory stat = do mode <- st_mode stat return (s_isdir mode) fileNameEndClean :: String -> String fileNameEndClean name = if isDrive name then addTrailingPathSeparator name else dropTrailingPathSeparator name foreign import ccall unsafe "HsDirectory.h __hscore_S_IRUSR" s_IRUSR :: CMode foreign import ccall unsafe "HsDirectory.h __hscore_S_IWUSR" s_IWUSR :: CMode foreign import ccall unsafe "HsDirectory.h __hscore_S_IXUSR" s_IXUSR :: CMode foreign import ccall unsafe "__hscore_S_IFDIR" s_IFDIR :: CMode foreign import ccall unsafe "__hscore_long_path_size" long_path_size :: Int {- | Returns the current user's home directory. The directory returned is expected to be writable by the current user, but note that it isn't generally considered good practice to store application-specific data here; use 'getAppUserDataDirectory' instead. On Unix, 'getHomeDirectory' returns the value of the @HOME@ environment variable. On Windows, the system is queried for a suitable path; a typical path might be @C:/Documents And Settings/user@. The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of home directory. * 'isDoesNotExistError' The home directory for the current user does not exist, or cannot be found. -} getHomeDirectory :: IO FilePath getHomeDirectory = modifyIOError ((`ioeSetLocation` "getHomeDirectory")) $ do r <- try $ Win32.sHGetFolderPath nullPtr Win32.cSIDL_PROFILE nullPtr 0 case (r :: Either IOException String) of Right s -> return s Left _ -> do r1 <- try $ Win32.sHGetFolderPath nullPtr Win32.cSIDL_WINDOWS nullPtr 0 case r1 of Right s -> return s Left e -> ioError (e :: IOException) {- | Returns the pathname of a directory in which application-specific data for the current user can be stored. The result of 'getAppUserDataDirectory' for a given application is specific to the current user. The argument should be the name of the application, which will be used to construct the pathname (so avoid using unusual characters that might result in an invalid pathname). Note: the directory may not actually exist, and may need to be created first. It is expected that the parent directory exists and is writable. On Unix, this function returns @$HOME\/.appName@. On Windows, a typical path might be > C:/Documents And Settings/user/Application Data/appName The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of application-specific data directory. * 'isDoesNotExistError' The home directory for the current user does not exist, or cannot be found. -} getAppUserDataDirectory :: String -> IO FilePath getAppUserDataDirectory appName = do modifyIOError ((`ioeSetLocation` "getAppUserDataDirectory")) $ do s <- Win32.sHGetFolderPath nullPtr Win32.cSIDL_APPDATA nullPtr 0 return (s++'\\':appName) {- | Returns the current user's document directory. The directory returned is expected to be writable by the current user, but note that it isn't generally considered good practice to store application-specific data here; use 'getAppUserDataDirectory' instead. On Unix, 'getUserDocumentsDirectory' returns the value of the @HOME@ environment variable. On Windows, the system is queried for a suitable path; a typical path might be @C:\/Documents and Settings\/user\/My Documents@. The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of document directory. * 'isDoesNotExistError' The document directory for the current user does not exist, or cannot be found. -} getUserDocumentsDirectory :: IO FilePath getUserDocumentsDirectory = do modifyIOError ((`ioeSetLocation` "getUserDocumentsDirectory")) $ do Win32.sHGetFolderPath nullPtr Win32.cSIDL_PERSONAL nullPtr 0 {- | Returns the current directory for temporary files. On Unix, 'getTemporaryDirectory' returns the value of the @TMPDIR@ environment variable or \"\/tmp\" if the variable isn\'t defined. On Windows, the function checks for the existence of environment variables in the following order and uses the first path found: * TMP environment variable. * TEMP environment variable. * USERPROFILE environment variable. * The Windows directory The operation may fail with: * 'UnsupportedOperation' The operating system has no notion of temporary directory. The function doesn\'t verify whether the path exists. -} getTemporaryDirectory :: IO FilePath getTemporaryDirectory = do Win32.getTemporaryDirectory -- ToDo: This should be determined via autoconf (AC_EXEEXT) -- | Extension for executable files -- (typically @\"\"@ on Unix and @\"exe\"@ on Windows or OS\/2) exeExtension :: String exeExtension = "exe"