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<pre><a name="line-1"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-2"></a><span class='hs-comment'>-- |</span>
<a name="line-3"></a><span class='hs-comment'>-- Module : XMonad.Util.Run</span>
<a name="line-4"></a><span class='hs-comment'>-- Copyright : (C) 2007 Spencer Janssen, Andrea Rossato, glasser@mit.edu</span>
<a name="line-5"></a><span class='hs-comment'>-- License : BSD-style (see LICENSE)</span>
<a name="line-6"></a><span class='hs-comment'>--</span>
<a name="line-7"></a><span class='hs-comment'>-- Maintainer : Christian Thiemann <mail@christian-thiemann.de></span>
<a name="line-8"></a><span class='hs-comment'>-- Stability : unstable</span>
<a name="line-9"></a><span class='hs-comment'>-- Portability : unportable</span>
<a name="line-10"></a><span class='hs-comment'>--</span>
<a name="line-11"></a><span class='hs-comment'>-- This modules provides several commands to run an external process.</span>
<a name="line-12"></a><span class='hs-comment'>-- It is composed of functions formerly defined in "XMonad.Util.Dmenu" (by</span>
<a name="line-13"></a><span class='hs-comment'>-- Spencer Janssen), "XMonad.Util.Dzen" (by glasser\@mit.edu) and</span>
<a name="line-14"></a><span class='hs-comment'>-- XMonad.Util.RunInXTerm (by Andrea Rossato).</span>
<a name="line-15"></a><span class='hs-comment'>--</span>
<a name="line-16"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-17"></a>
<a name="line-18"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>XMonad</span><span class='hs-varop'>.</span><span class='hs-conid'>Util</span><span class='hs-varop'>.</span><span class='hs-conid'>Run</span> <span class='hs-layout'>(</span>
<a name="line-19"></a> <span class='hs-comment'>-- * Usage</span>
<a name="line-20"></a> <span class='hs-comment'>-- $usage</span>
<a name="line-21"></a> <span class='hs-varid'>runProcessWithInput</span><span class='hs-layout'>,</span>
<a name="line-22"></a> <span class='hs-varid'>runProcessWithInputAndWait</span><span class='hs-layout'>,</span>
<a name="line-23"></a> <span class='hs-varid'>safeSpawn</span><span class='hs-layout'>,</span>
<a name="line-24"></a> <span class='hs-varid'>safeSpawnProg</span><span class='hs-layout'>,</span>
<a name="line-25"></a> <span class='hs-varid'>unsafeSpawn</span><span class='hs-layout'>,</span>
<a name="line-26"></a> <span class='hs-varid'>runInTerm</span><span class='hs-layout'>,</span>
<a name="line-27"></a> <span class='hs-varid'>safeRunInTerm</span><span class='hs-layout'>,</span>
<a name="line-28"></a> <span class='hs-varid'>seconds</span><span class='hs-layout'>,</span>
<a name="line-29"></a> <span class='hs-varid'>spawnPipe</span><span class='hs-layout'>,</span>
<a name="line-30"></a>
<a name="line-31"></a> <span class='hs-varid'>hPutStr</span><span class='hs-layout'>,</span> <span class='hs-varid'>hPutStrLn</span> <span class='hs-comment'>-- re-export for convenience</span>
<a name="line-32"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-33"></a>
<a name="line-34"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Codec</span><span class='hs-varop'>.</span><span class='hs-conid'>Binary</span><span class='hs-varop'>.</span><span class='hs-conid'>UTF8</span><span class='hs-varop'>.</span><span class='hs-conid'>String</span>
<a name="line-35"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Posix</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span>
<a name="line-36"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Posix</span><span class='hs-varop'>.</span><span class='hs-conid'>Process</span> <span class='hs-layout'>(</span><span class='hs-varid'>createSession</span><span class='hs-layout'>,</span> <span class='hs-varid'>executeFile</span><span class='hs-layout'>,</span> <span class='hs-varid'>forkProcess</span><span class='hs-layout'>)</span>
<a name="line-37"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span> <span class='hs-layout'>(</span><span class='hs-varid'>threadDelay</span><span class='hs-layout'>)</span>
<a name="line-38"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span>
<a name="line-39"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Process</span> <span class='hs-layout'>(</span><span class='hs-varid'>runInteractiveProcess</span><span class='hs-layout'>)</span>
<a name="line-40"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>XMonad</span>
<a name="line-41"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span>
<a name="line-42"></a>
<a name="line-43"></a><span class='hs-comment'>-- $usage</span>
<a name="line-44"></a><span class='hs-comment'>-- For an example usage of 'runInTerm' see "XMonad.Prompt.Ssh"</span>
<a name="line-45"></a><span class='hs-comment'>--</span>
<a name="line-46"></a><span class='hs-comment'>-- For an example usage of 'runProcessWithInput' see</span>
<a name="line-47"></a><span class='hs-comment'>-- "XMonad.Prompt.DirectoryPrompt", "XMonad.Util.Dmenu",</span>
<a name="line-48"></a><span class='hs-comment'>-- "XMonad.Prompt.ShellPrompt", "XMonad.Actions.WmiiActions",</span>
<a name="line-49"></a><span class='hs-comment'>-- "XMonad.Prompt.WorkspaceDir"</span>
<a name="line-50"></a><span class='hs-comment'>--</span>
<a name="line-51"></a><span class='hs-comment'>-- For an example usage of 'runProcessWithInputAndWait' see</span>
<a name="line-52"></a><span class='hs-comment'>-- "XMonad.Util.Dzen"</span>
<a name="line-53"></a>
<a name="line-54"></a><a name="runProcessWithInput"></a><span class='hs-comment'>-- | Returns the output.</span>
<a name="line-55"></a><span class='hs-definition'>runProcessWithInput</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>String</span>
<a name="line-56"></a><span class='hs-definition'>runProcessWithInput</span> <span class='hs-varid'>cmd</span> <span class='hs-varid'>args</span> <span class='hs-varid'>input</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-57"></a> <span class='hs-layout'>(</span><span class='hs-varid'>pin</span><span class='hs-layout'>,</span> <span class='hs-varid'>pout</span><span class='hs-layout'>,</span> <span class='hs-varid'>perr</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>runInteractiveProcess</span> <span class='hs-layout'>(</span><span class='hs-varid'>encodeString</span> <span class='hs-varid'>cmd</span><span class='hs-layout'>)</span>
<a name="line-58"></a> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>encodeString</span> <span class='hs-varid'>args</span><span class='hs-layout'>)</span> <span class='hs-conid'>Nothing</span> <span class='hs-conid'>Nothing</span>
<a name="line-59"></a> <span class='hs-varid'>hPutStr</span> <span class='hs-varid'>pin</span> <span class='hs-varid'>input</span>
<a name="line-60"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>pin</span>
<a name="line-61"></a> <span class='hs-varid'>output</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>hGetContents</span> <span class='hs-varid'>pout</span>
<a name="line-62"></a> <span class='hs-varid'>when</span> <span class='hs-layout'>(</span><span class='hs-varid'>output</span> <span class='hs-varop'>==</span> <span class='hs-varid'>output</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-63"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>pout</span>
<a name="line-64"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>perr</span>
<a name="line-65"></a> <span class='hs-comment'>-- no need to waitForProcess, we ignore SIGCHLD</span>
<a name="line-66"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>output</span>
<a name="line-67"></a>
<a name="line-68"></a><a name="runProcessWithInputAndWait"></a><span class='hs-comment'>-- | Wait is in &#956; (microseconds)</span>
<a name="line-69"></a><span class='hs-definition'>runProcessWithInputAndWait</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Int</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-70"></a><span class='hs-definition'>runProcessWithInputAndWait</span> <span class='hs-varid'>cmd</span> <span class='hs-varid'>args</span> <span class='hs-varid'>input</span> <span class='hs-varid'>timeout</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-71"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>xfork</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-72"></a> <span class='hs-layout'>(</span><span class='hs-varid'>pin</span><span class='hs-layout'>,</span> <span class='hs-varid'>pout</span><span class='hs-layout'>,</span> <span class='hs-varid'>perr</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>runInteractiveProcess</span> <span class='hs-layout'>(</span><span class='hs-varid'>encodeString</span> <span class='hs-varid'>cmd</span><span class='hs-layout'>)</span>
<a name="line-73"></a> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>encodeString</span> <span class='hs-varid'>args</span><span class='hs-layout'>)</span> <span class='hs-conid'>Nothing</span> <span class='hs-conid'>Nothing</span>
<a name="line-74"></a> <span class='hs-varid'>hPutStr</span> <span class='hs-varid'>pin</span> <span class='hs-varid'>input</span>
<a name="line-75"></a> <span class='hs-varid'>hFlush</span> <span class='hs-varid'>pin</span>
<a name="line-76"></a> <span class='hs-varid'>threadDelay</span> <span class='hs-varid'>timeout</span>
<a name="line-77"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>pin</span>
<a name="line-78"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>pout</span>
<a name="line-79"></a> <span class='hs-varid'>hClose</span> <span class='hs-varid'>perr</span>
<a name="line-80"></a> <span class='hs-comment'>-- no need to waitForProcess, we ignore SIGCHLD</span>
<a name="line-81"></a> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-82"></a> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-83"></a>
<a name="line-84"></a><a name="seconds"></a><span class='hs-comment'>-- | Multiplies by ONE MILLION, for functions that take microseconds.</span>
<a name="line-85"></a><span class='hs-comment'>--</span>
<a name="line-86"></a><span class='hs-comment'>-- Use like:</span>
<a name="line-87"></a><span class='hs-comment'>--</span>
<a name="line-88"></a><span class='hs-comment'>-- > (5.5 `seconds`)</span>
<a name="line-89"></a><span class='hs-comment'>--</span>
<a name="line-90"></a><span class='hs-comment'>-- In GHC 7 and later, you must either enable the PostfixOperators extension</span>
<a name="line-91"></a><span class='hs-comment'>-- (by adding</span>
<a name="line-92"></a><span class='hs-comment'>--</span>
<a name="line-93"></a><span class='hs-comment'>-- > {-# LANGUAGE PostfixOperators #-}</span>
<a name="line-94"></a><span class='hs-comment'>--</span>
<a name="line-95"></a><span class='hs-comment'>-- to the top of your file) or use seconds in prefix form:</span>
<a name="line-96"></a><span class='hs-comment'>--</span>
<a name="line-97"></a><span class='hs-comment'>-- > 5.5 seconds</span>
<a name="line-98"></a><span class='hs-definition'>seconds</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Rational</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Int</span>
<a name="line-99"></a><span class='hs-definition'>seconds</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fromEnum</span> <span class='hs-varop'>.</span> <span class='hs-layout'>(</span><span class='hs-varop'>*</span> <span class='hs-num'>1000000</span><span class='hs-layout'>)</span>
<a name="line-100"></a>
<a name="line-101"></a><a name="safeSpawn"></a><span class='hs-comment'>{- | 'safeSpawn' bypasses 'spawn', because spawn passes
<a name="line-102"></a>strings to \/bin\/sh to be interpreted as shell commands. This is
<a name="line-103"></a>often what one wants, but in many cases the passed string will contain
<a name="line-104"></a>shell metacharacters which one does not want interpreted as such (URLs
<a name="line-105"></a>particularly often have shell metacharacters like \'&\' in them). In
<a name="line-106"></a>this case, it is more useful to specify a file or program to be run
<a name="line-107"></a>and a string to give it as an argument so as to bypass the shell and
<a name="line-108"></a>be certain the program will receive the string as you typed it.
<a name="line-109"></a>
<a name="line-110"></a>Examples:
<a name="line-111"></a>
<a name="line-112"></a>> , ((modm, xK_Print), unsafeSpawn "import -window root $HOME/xwd-$(date +%s)$$.png")
<a name="line-113"></a>> , ((modm, xK_d ), safeSpawn "firefox" [])
<a name="line-114"></a>
<a name="line-115"></a>Note that the unsafeSpawn example must be unsafe and not safe because
<a name="line-116"></a>it makes use of shell interpretation by relying on @$HOME@ and
<a name="line-117"></a>interpolation, whereas the safeSpawn example can be safe because
<a name="line-118"></a>Firefox doesn't need any arguments if it is just being started. -}</span>
<a name="line-119"></a><span class='hs-definition'>safeSpawn</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-120"></a><span class='hs-definition'>safeSpawn</span> <span class='hs-varid'>prog</span> <span class='hs-varid'>args</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span> <span class='hs-varop'>$</span> <span class='hs-varid'>void_</span> <span class='hs-varop'>$</span> <span class='hs-varid'>forkProcess</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-121"></a> <span class='hs-varid'>uninstallSignalHandlers</span>
<a name="line-122"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>createSession</span>
<a name="line-123"></a> <span class='hs-varid'>executeFile</span> <span class='hs-layout'>(</span><span class='hs-varid'>encodeString</span> <span class='hs-varid'>prog</span><span class='hs-layout'>)</span> <span class='hs-conid'>True</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>encodeString</span> <span class='hs-varid'>args</span><span class='hs-layout'>)</span> <span class='hs-conid'>Nothing</span>
<a name="line-124"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>void_</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varop'>>></span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- TODO: replace with Control.Monad.void / void not in ghc6 apparently</span>
<a name="line-125"></a>
<a name="line-126"></a><a name="safeSpawnProg"></a><span class='hs-comment'>-- | Simplified 'safeSpawn'; only takes a program (and no arguments):</span>
<a name="line-127"></a><span class='hs-comment'>--</span>
<a name="line-128"></a><span class='hs-comment'>-- > , ((modm, xK_d ), safeSpawnProg "firefox")</span>
<a name="line-129"></a><span class='hs-definition'>safeSpawnProg</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-130"></a><span class='hs-definition'>safeSpawnProg</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>flip</span> <span class='hs-varid'>safeSpawn</span> <span class='hs-conid'>[]</span>
<a name="line-131"></a>
<a name="line-132"></a><a name="unsafeSpawn"></a><span class='hs-comment'>-- | An alias for 'spawn'; the name emphasizes that one is calling out to a</span>
<a name="line-133"></a><span class='hs-comment'>-- Turing-complete interpreter which may do things one dislikes; for details, see 'safeSpawn'.</span>
<a name="line-134"></a><span class='hs-definition'>unsafeSpawn</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>()</span>
<a name="line-135"></a><span class='hs-definition'>unsafeSpawn</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>spawn</span>
<a name="line-136"></a>
<a name="line-137"></a><a name="unsafeRunInTerm"></a><span class='hs-comment'>-- | Open a terminal emulator. The terminal emulator is specified in @defaultConfig@ as xterm by default. It is then</span>
<a name="line-138"></a><span class='hs-comment'>-- asked to pass the shell a command with certain options. This is unsafe in the sense of 'unsafeSpawn'</span>
<a name="line-139"></a><span class='hs-definition'>unsafeRunInTerm</span><span class='hs-layout'>,</span> <span class='hs-varid'>runInTerm</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>X</span> <span class='hs-conid'>()</span>
<a name="line-140"></a><span class='hs-definition'>unsafeRunInTerm</span> <span class='hs-varid'>options</span> <span class='hs-varid'>command</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>asks</span> <span class='hs-layout'>(</span><span class='hs-varid'>terminal</span> <span class='hs-varop'>.</span> <span class='hs-varid'>config</span><span class='hs-layout'>)</span> <span class='hs-varop'>>>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>t</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>unsafeSpawn</span> <span class='hs-varop'>$</span> <span class='hs-varid'>t</span> <span class='hs-varop'>++</span> <span class='hs-str'>" "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>options</span> <span class='hs-varop'>++</span> <span class='hs-str'>" -e "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>command</span>
<a name="line-141"></a><a name="runInTerm"></a><span class='hs-definition'>runInTerm</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>unsafeRunInTerm</span>
<a name="line-142"></a>
<a name="line-143"></a><a name="safeRunInTerm"></a><span class='hs-comment'>-- | Run a given program in the preferred terminal emulator; see 'runInTerm'. This makes use of 'safeSpawn'.</span>
<a name="line-144"></a><span class='hs-definition'>safeRunInTerm</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>X</span> <span class='hs-conid'>()</span>
<a name="line-145"></a><span class='hs-definition'>safeRunInTerm</span> <span class='hs-varid'>options</span> <span class='hs-varid'>command</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>asks</span> <span class='hs-layout'>(</span><span class='hs-varid'>terminal</span> <span class='hs-varop'>.</span> <span class='hs-varid'>config</span><span class='hs-layout'>)</span> <span class='hs-varop'>>>=</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>t</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>safeSpawn</span> <span class='hs-varid'>t</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>options</span><span class='hs-layout'>,</span> <span class='hs-str'>" -e "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>command</span><span class='hs-keyglyph'>]</span>
<a name="line-146"></a>
<a name="line-147"></a><a name="spawnPipe"></a><span class='hs-comment'>-- | Launch an external application through the system shell and return a @Handle@ to its standard input.</span>
<a name="line-148"></a><span class='hs-definition'>spawnPipe</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MonadIO</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>m</span> <span class='hs-conid'>Handle</span>
<a name="line-149"></a><span class='hs-definition'>spawnPipe</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>io</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-150"></a> <span class='hs-layout'>(</span><span class='hs-varid'>rd</span><span class='hs-layout'>,</span> <span class='hs-varid'>wr</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>createPipe</span>
<a name="line-151"></a> <span class='hs-varid'>setFdOption</span> <span class='hs-varid'>wr</span> <span class='hs-conid'>CloseOnExec</span> <span class='hs-conid'>True</span>
<a name="line-152"></a> <span class='hs-varid'>h</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>fdToHandle</span> <span class='hs-varid'>wr</span>
<a name="line-153"></a> <span class='hs-varid'>hSetBuffering</span> <span class='hs-varid'>h</span> <span class='hs-conid'>LineBuffering</span>
<a name="line-154"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>xfork</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-155"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>dupTo</span> <span class='hs-varid'>rd</span> <span class='hs-varid'>stdInput</span>
<a name="line-156"></a> <span class='hs-varid'>executeFile</span> <span class='hs-str'>"/bin/sh"</span> <span class='hs-conid'>False</span> <span class='hs-keyglyph'>[</span><span class='hs-str'>"-c"</span><span class='hs-layout'>,</span> <span class='hs-varid'>encodeString</span> <span class='hs-varid'>x</span><span class='hs-keyglyph'>]</span> <span class='hs-conid'>Nothing</span>
<a name="line-157"></a> <span class='hs-varid'>closeFd</span> <span class='hs-varid'>rd</span>
<a name="line-158"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>h</span>
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