-----------------------------------------------------------------------------
-- |
-- Module : XMonadContrib.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 XMonadContrib.Dmenu (by
-- Spenver Jannsen), XMonadContrib.Dzen (by glasser@mit.edu) and
-- XMonadContrib.RunInXTerm (by Andrea Rossato).
--
-----------------------------------------------------------------------------
module XMonadContrib.Run (
-- * Usage
-- $usage
runProcessWithInput,
runProcessWithInputAndWait,
safeSpawn,
unsafeSpawn,
seconds
) where
import Control.Monad.State (Monad((>>), return), when)
import System.Posix.Process (createSession, forkProcess, executeFile,
getProcessStatus)
import Control.Concurrent (threadDelay)
import Control.Exception (try)
import System.Exit (ExitCode(ExitSuccess), exitWith)
import System.IO (IO, FilePath, hPutStr, hGetContents, hFlush, hClose)
import System.Process (runInteractiveProcess, waitForProcess)
import XMonad (X, io, spawn)
-- $usage
-- For an example usage of runInXTerm see XMonadContrib.SshPrompt
--
-- For an example usage of runProcessWithInput see
-- XMonadContrib.{DirectoryPrompt,Dmenu,ShellPrompt,WmiiActions,WorkspaceDir}
--
-- For an example usage of runProcessWithInputAndWait see XMonadContrib.Dzen
-- | Returns Just output if the command succeeded, and Nothing if it didn't.
-- 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 us
runProcessWithInputAndWait :: FilePath -> [String] -> String -> Int -> IO ()
runProcessWithInputAndWait cmd args input timeout = do
pid <- forkProcess $ do
forkProcess $ do -- double fork it over to init
createSession
(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 ()
exitWith ExitSuccess
return ()
getProcessStatus True False pid
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 :: FilePath -> String -> X ()
safeSpawn prog arg = io (try (forkProcess $ executeFile prog True [arg] Nothing) >> return ())
unsafeSpawn :: String -> X ()
unsafeSpawn = spawn
