-----------------------------------------------------------------------------
-- |
-- Module : XMonad.Util.Run
-- Copyright : (C) 2007 Spencer Janssen, Andrea Rossato, glasser@mit.edu
-- License : BSD-style (see LICENSE)
--
-- Maintainer : Christian Thiemann <mail@christian-thiemann.de>
-- Stability : unstable
-- Portability : unportable
--
-- This modules provides several commands to run an external process.
-- It is composed of functions formerly defined in "XMonad.Util.Dmenu" (by
-- Spencer Janssen), "XMonad.Util.Dzen" (by glasser\@mit.edu) and
-- XMonad.Util.RunInXTerm (by Andrea Rossato).
--
-----------------------------------------------------------------------------
module XMonad.Util.Run (
-- * Usage
-- $usage
runProcessWithInput,
runProcessWithInputAndWait,
safeSpawn,
unsafeSpawn,
runInTerm,
safeRunInTerm,
seconds,
spawnPipe
) where
import System.Posix.IO
import System.Posix.Process (executeFile)
import Control.Concurrent (threadDelay)
import Control.Exception (try)
import System.IO
import System.Process (runInteractiveProcess, waitForProcess)
import XMonad
import Control.Monad
-- $usage
-- For an example usage of 'runInTerm' see "XMonad.Prompt.Ssh"
--
-- For an example usage of 'runProcessWithInput' see
-- "XMonad.Prompt.DirectoryPrompt", "XMonad.Util.Dmenu",
-- "XMonad.Prompt.ShellPrompt", "XMonad.Actions.WmiiActions",
-- "XMonad.Prompt.WorkspaceDir"
--
-- For an example usage of 'runProcessWithInputAndWait' see
-- "XMonad.Util.Dzen"
-- | Return output if the command succeeded, otherwise return @()@.
-- This corresponds to dmenu's notion of exit code 1 for a cancelled invocation.
runProcessWithInput :: FilePath -> [String] -> String -> IO String
runProcessWithInput cmd args input = do
(pin, pout, perr, ph) <- runInteractiveProcess cmd args Nothing Nothing
hPutStr pin input
hClose pin
output <- hGetContents pout
when (output == output) $ return ()
hClose pout
hClose perr
waitForProcess ph
return output
-- | Wait is in µs (microseconds)
runProcessWithInputAndWait :: FilePath -> [String] -> String -> Int -> IO ()
runProcessWithInputAndWait cmd args input timeout = do
doubleFork $ do
(pin, pout, perr, ph) <- runInteractiveProcess cmd args Nothing Nothing
hPutStr pin input
hFlush pin
threadDelay timeout
hClose pin
hClose pout
hClose perr
waitForProcess ph
return ()
-- | Multiplies by ONE MILLION, for use with
-- 'runProcessWithInputAndWait'.
--
-- Use like:
--
-- > (5.5 `seconds`)
seconds :: Rational -> Int
seconds = fromEnum . (* 1000000)
-- | safeSpawn bypasses XMonad's 'spawn' command, because 'spawn' passes
-- strings to \/bin\/sh to be interpreted as shell commands. This is
-- often what one wants, but in many cases the passed string will contain
-- shell metacharacters which one does not want interpreted as such (URLs
-- particularly often have shell metacharacters like \'&\' in them). In
-- this case, it is more useful to specify a file or program to be run
-- and a string to give it as an argument so as to bypass the shell and
-- be certain the program will receive the string as you typed it.
-- unsafeSpawn is an alias for XMonad's 'spawn', to remind one that use
-- of it can be, well, unsafe.
-- Examples:
--
-- > , ((modMask, xK_Print), unsafeSpawn "import -window root png:$HOME/xwd-$(date +%s)$$.png")
-- > , ((modMask, xK_d ), safeSpawn "firefox" "")
--
-- Note that the unsafeSpawn example must be unsafe and not safe because
-- it makes use of shell interpretation by relying on @$HOME@ and
-- interpolation, whereas the safeSpawn example can be safe because
-- Firefox doesn't need any arguments if it is just being started.
safeSpawn :: MonadIO m => FilePath -> String -> m ()
safeSpawn prog arg = liftIO (try (doubleFork $ executeFile prog True [arg] Nothing) >> return ())
unsafeSpawn :: MonadIO m => String -> m ()
unsafeSpawn = spawn
-- | Run a given program in the preferred terminal emulator. This uses
-- 'safeSpawn'.
safeRunInTerm :: String -> String -> X ()
safeRunInTerm options command = asks (terminal . config) >>= \t -> safeSpawn t (options ++ " -e " ++ command)
unsafeRunInTerm, runInTerm :: String -> String -> X ()
unsafeRunInTerm options command = asks (terminal . config) >>= \t -> unsafeSpawn $ t ++ " " ++ options ++ " -e " ++ command
runInTerm = unsafeRunInTerm
-- | Launch an external application and return a 'Handle' to its standard input.
spawnPipe :: String -> IO Handle
spawnPipe x = do
(rd, wr) <- createPipe
setFdOption wr CloseOnExec True
h <- fdToHandle wr
hSetBuffering h LineBuffering
doubleFork $ do
dupTo rd stdInput
executeFile "/bin/sh" False ["-c", x] Nothing
return h
