{-# LINE 1 "libraries/unix/System/Posix/IO.hsc" #-}

{-# LINE 2 "libraries/unix/System/Posix/IO.hsc" #-}
{-# LANGUAGE Safe #-}

{-# LINE 6 "libraries/unix/System/Posix/IO.hsc" #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  System.Posix.IO
-- Copyright   :  (c) The University of Glasgow 2002
-- License     :  BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  non-portable (requires POSIX)
--
-- POSIX IO support.  These types and functions correspond to the unix
-- functions open(2), close(2), etc.  For more portable functions
-- which are more like fopen(3) and friends from stdio.h, see
-- "System.IO".
--
-----------------------------------------------------------------------------



module System.Posix.IO (
    -- * Input \/ Output

    -- ** Standard file descriptors
    stdInput, stdOutput, stdError,

    -- ** Opening and closing files
    OpenMode(..),
    OpenFileFlags(..), defaultFileFlags,
    openFd, createFile,
    closeFd,

    -- ** Reading\/writing data
    -- |Programmers using the 'fdRead' and 'fdWrite' API should be aware that
    -- EAGAIN exceptions may occur for non-blocking IO!

    fdRead, fdWrite,
    fdReadBuf, fdWriteBuf,

    -- ** Seeking
    fdSeek,

    -- ** File options
    FdOption(..),
    queryFdOption,
    setFdOption,

    -- ** Locking
    FileLock,
    LockRequest(..),
    getLock,  setLock,
    waitToSetLock,

    -- ** Pipes
    createPipe,

    -- ** Duplicating file descriptors
    dup, dupTo,

    -- ** Converting file descriptors to\/from Handles
    handleToFd,
    fdToHandle,

  ) where

import System.Posix.Types
import System.Posix.Error
import System.Posix.IO.Common
import System.Posix.Internals ( withFilePath )

-- |Open and optionally create this file.  See 'System.Posix.Files'
-- for information on how to use the 'FileMode' type.
openFd :: FilePath
       -> OpenMode
       -> Maybe FileMode -- ^Just x => creates the file with the given modes, Nothing => the file must exist.
       -> OpenFileFlags
       -> IO Fd
openFd :: FilePath -> OpenMode -> Maybe FileMode -> OpenFileFlags -> IO Fd
openFd FilePath
name OpenMode
how Maybe FileMode
maybe_mode OpenFileFlags
flags = do
   FilePath -> (CString -> IO Fd) -> IO Fd
forall a. FilePath -> (CString -> IO a) -> IO a
withFilePath FilePath
name ((CString -> IO Fd) -> IO Fd) -> (CString -> IO Fd) -> IO Fd
forall a b. (a -> b) -> a -> b
$ \CString
str -> do
     FilePath -> FilePath -> IO Fd -> IO Fd
forall a. (Eq a, Num a) => FilePath -> FilePath -> IO a -> IO a
throwErrnoPathIfMinus1Retry FilePath
"openFd" FilePath
name (IO Fd -> IO Fd) -> IO Fd -> IO Fd
forall a b. (a -> b) -> a -> b
$
       CString -> OpenMode -> Maybe FileMode -> OpenFileFlags -> IO Fd
open_ CString
str OpenMode
how Maybe FileMode
maybe_mode OpenFileFlags
flags

-- |Create and open this file in WriteOnly mode.  A special case of
-- 'openFd'.  See 'System.Posix.Files' for information on how to use
-- the 'FileMode' type.

createFile :: FilePath -> FileMode -> IO Fd
createFile :: FilePath -> FileMode -> IO Fd
createFile FilePath
name FileMode
mode
  = FilePath -> OpenMode -> Maybe FileMode -> OpenFileFlags -> IO Fd
openFd FilePath
name OpenMode
WriteOnly (FileMode -> Maybe FileMode
forall a. a -> Maybe a
Just FileMode
mode) OpenFileFlags
defaultFileFlags{ trunc :: Bool
trunc=Bool
True }