In order to install, unpack the source distribution somewhere. Go to the - directory, and call make. This will compile and install the library, - locally, as a user package. The location of the API documentation - is ~/.cabal/share/doc/hsshellscript-3.2.0/html/index.html. + directory, and call make. This will compile the library. If you want + to install it locally, in your user account, then do make + install-user. This calls cabal install --user. If you want to + install the library globally, do make install-global. You will be + prompted for the root password, which is needed in this case. This + calls sudo cabal install --global. +
If installed as a user package, then the location of the API documentation + is ~/.cabal/share/doc/hsshellscript-3.3.0/html/index.html. If it is + installed globaly, it + is /usr/local/share/doc/hsshellscript-3.3.0/html/index.html. +
Cabal's Simple Build Infrastructure doesn't provide any means to add extra documenation to a project. Therefore the user manual isn't installed by default. If you need it, you can just copy the "manual" directory anywhere you like, but the Makefile privides the make target install-manual, which copies the files to /usr/local/share/hsshellscript/manual. - "make" must be run as root.
Further information about the Cabal can be found here: diff --git a/src/HsShellScript/ProcErr.chs b/src/HsShellScript/ProcErr.chs --- a/src/HsShellScript/ProcErr.chs +++ b/src/HsShellScript/ProcErr.chs @@ -490,6 +490,10 @@ /The exit code of q is silently ignored./ The process ID of the forked copy of @q@ isn't returned to the caller, so it's lost. + The pipe, which connects @p@ and @q@, is in /text mode/. This means that the + output of @p@ is converted from Unicode to the system character set, which + is determined by the environment variable @LANG@. + See "HsShellScript#subr" and "HsShellScript#exec" for further details. @@ -504,7 +508,7 @@ > ) > ) - See 'subproc', '(=|-)', '(-|=)'. + See 'subproc', '(=|-)', '(-|=)', 'redirect' -} (-|-) :: IO a -- ^ Action which won't be forked -> IO b -- ^ Action which will be forked and connected with a pipe @@ -530,6 +534,10 @@ /The exit code of q is silently ignored./ The process ID of the forked copy of @q@ isn't returned to the caller, so it's lost. + The pipe, which connects @p@ and @q@, is in /text mode/. This means that the + output of @p@ is converted from Unicode to the system character set, which + is determined by the environment variable @LANG@. + See "HsShellScript#subr" and "HsShellScript#exec" for further details. @@ -564,6 +572,10 @@ /The exit code of p is silently ignored./ The process ID of the forked copy of @q@ isn't returned to the caller, so it's lost. + The pipe, which connects @p@ and @q@, is in /text mode/. This means that the + output of @p@ is converted from Unicode to the system character set, which + is determined by the environment variable @LANG@. + See "HsShellScript#subr" and "HsShellScript#exec" for further details. @@ -597,6 +609,10 @@ /The exit code of p is silently ignored./ The process ID of the forked copy of @q@ isn't returned to the caller, so it's lost. + The pipe, which connects @p@ and @q@, is in /text mode/. This means that the + output of @p@ is converted from Unicode to the system character set, which + is determined by the environment variable @LANG@. + See "HsShellScript#subr" and "HsShellScript#exec" for further details. @@ -647,6 +663,15 @@ redirect_helper stdh mode io path = do h <- openFile path mode + + -- The file in a redirection is accessed in /text mode/, If stdout or stderr + -- are redirected, this means that output is converted from ghc's Unicode to + -- the system character set. If stdin is redirected, this means that data + -- read from the file is converted from the system character set to ghc's + -- Unicode. The system character set is taken from the environment variable + -- LANG. + hSetBinaryMode h False + res <- redirect stdh h io hClose h return res @@ -658,9 +683,13 @@ @exec@ functions know about this. See "HsShellScript#fdpipes" and "HsShellScript#exec" for details. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + Example: ->run "/some/program" [] ->- "/tmp/output" +>runprog "/some/program" [] ->- "/tmp/output" Note: You can't redirect to @\"\/dev\/null\"@ this way, because GHC 6.4's @openFile@ throws an \"invalid argument\" IOError. (This may be a bug in the GHC 6.4 libraries). Use @->>-@ instead. @@ -670,8 +699,8 @@ (->-) :: IO a -- ^ Action, whose output will be redirected -> FilePath -- ^ File to redirect the output to -> IO a -- ^ Result action -(->-) = - redirect_helper stdout WriteMode +(->-) io path = + redirect_helper stdout WriteMode io path {- | Redirect the standard output of the specified IO action to a file. If the file already exists, the output will be appended. @@ -680,6 +709,10 @@ @exec@ functions know about this. See "HsShellScript#fdpipes" and "HsShellScript#exec" for details. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + Example: >run "/some/noisy/program" [] ->>- "/dev/null" @@ -689,8 +722,8 @@ (->>-) :: IO a -- ^ Action, whose output will be redirected -> FilePath -- ^ File to redirect the output to -> IO a -- ^ Result action -(->>-) = - redirect_helper stdout AppendMode +(->>-) io path = + redirect_helper stdout AppendMode io path {- | Redirect the standard error output of the specified IO action to a file. If the file already exists, it will be overwritten. @@ -702,6 +735,10 @@ Note: You can't redirect to @\"\/dev\/null\"@ this way, because GHC 6.4's @openFile@ throws an \"invalid argument\" IOError. (This may be a bug in the GHC 6.4 libraries). Use @=>>-@ instead. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + Example: >run "/path/to/foo" [] =>- "/tmp/errlog" @@ -721,6 +758,10 @@ @exec@ functions know about this. See "HsShellScript#fdpipes" and "HsShellScript#exec" for details. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + Example: >run "/some/program" [] =>>- "/dev/null" @@ -745,6 +786,10 @@ Note: You can't redirect to @\"\/dev\/null\"@ this way, because GHC 6.4's @openFile@ throws an \"invalid argument\" IOError. (This may be a bug in the GHC 6.4 libraries). Use @-&>>-@ instead. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + >(-&>-) io path = err_to_out io ->- path Example: @@ -767,6 +812,10 @@ "HsShellScript#fdpipes" and "HsShellScript#exec" for details. +The file is written in /text mode/. This means that the +output is converted from Unicode to the system character set, which +is determined by the environment variable @LANG@. + >(-&>>-) io path = (err_to_out >> io) ->>- path Example: @@ -790,6 +839,10 @@ "HsShellScript#fdpipes" and "HsShellScript#exec" for details. +The file is read in /text mode/. This means that the input is converted from the +system character set to Unicode. The system's character set is determined by the +environment variable @LANG@. + Example: @call (exec \"\/path\/to\/foo\" [] -\<- \"bar\")@ @@ -897,6 +950,8 @@ do closeFd (if read then readend else writeend) let fd = if read then writeend else readend h <- System.Posix.fdToHandle fd + -- Use Text mode for the new handle by default. + hSetBinaryMode h False return (Just h) @@ -927,6 +982,12 @@ -- that no resources, which have been duplicated by the fork, cause problems. -- See "HsShellScript#subr" for details. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in +-- the text are converted to the system character set. If you need to pipe binary +-- data, you should use @h_pipe_to@, and set the returned handle to binary +-- mode. This is accomplished by @'hSetBinaryMode' h True@. The system +-- character set is determined by the environment variable @LANG@. +-- -- Example: -- -- >pipe_to "blah" (exec "/usr/bin/foo" ["bar"]) @@ -969,7 +1030,7 @@ -- the returned file handle. -- -- This gives you full control of the pipe, and of the forked process. But you --- must cope with the child process by yourself. +-- must cope with the child process by yourself. -- -- Unless you replace the child process, calling an @exec@ variant, the child -- should let the control flow leave the action normally. @@ -990,6 +1051,11 @@ -- corresponding @ProcessStatus@ is returned by @getProcessStatus@. See -- 'System.Posix.Process.getProcessStatus' for details. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text are converted to the system character set. You can set the returned +-- handle to binary mode, by calling @'hSetBinaryMode' handle True@. The system +-- character set is determined by the environment variable @LANG@. +-- -- Example: -- -- >(handle, pid) <- h_pipe_to $ exec "/usr/bin/foo" ["bar"] @@ -1042,6 +1108,13 @@ -- newline characters. The entire output of the action is returned. You might want -- to apply @chomp@ to the result. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from stdin, is converted from the system character set to +-- Unicode. The system character set is determined by the environment variable +-- @LANG@. If you need to read binary data from the forked process, you should use +-- @h_pipe_from@ and set the returned handle to binary mode. This is +-- accomplished by @'hSetBinaryMode' h True@. +-- -- Example: -- -- >output <- pipe_from $ exec "/bin/mount" [] @@ -1116,6 +1189,13 @@ -- newline characters. The entire error output of the action is returned. You might want -- to apply @chomp@ to the result. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from stdin, is converted from the system character set to +-- Unicode. The system character set is determined by the environment variable +-- @LANG@. If you need to read binary data from the forked process, you should use +-- @h_pipe_from@ and set the returned handle to binary mode. This is +-- accomplished by @'hSetBinaryMode' h True@. +-- -- Example: -- -- >output <- pipe_from $ exec "/bin/mount" [] @@ -1156,7 +1236,7 @@ -- the returned file handle. -- -- This gives you full control of the pipe, and of the forked process. But you --- must cope with the child process by yourself. +-- must cope with the child process by yourself. -- -- When you call @getProcessStatus@ blockingly, you must first ensure that all -- data has been read, or close the handle. Otherwise you'll get a deadlock. @@ -1178,6 +1258,13 @@ -- @ArgError@, @ProcessStatus@, @RunError@, @IOError@ and @ExitCode@. Other -- exceptions result in the generic message, as produced by @show@. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from stdin, is converted from the system character set to +-- Unicode. The system character set is determined by the environment variable +-- @LANG@. If you need to read binary data from the forked process, you can set +-- the returned handle to binary mode. This is accomplished by @'hSetBinaryMode' +-- h True@. +-- -- Example: -- -- >(h,pid) <- h_pipe_from $ exec "/usr/bin/foo" ["bar"] @@ -1200,7 +1287,7 @@ -- the returned file handle. -- -- This gives you full control of the pipe, and of the forked process. But you --- must cope with the child process by yourself. +-- must cope with the child process by yourself. -- -- When you call @getProcessStatus@ blockingly, you must first ensure that all -- data has been read, or close the handle. Otherwise you'll get a deadlock. @@ -1222,6 +1309,13 @@ -- @ArgError@, @ProcessStatus@, @RunError@, @IOError@ and @ExitCode@. Other -- exceptions result in the generic message, as produced by @show@. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from stdin, is converted from the system character set to +-- Unicode. The system character set is determined by the environment variable +-- @LANG@. If you need to read binary data from the forked process, you can set +-- the returned handle to binary mode. This is accomplished by @'hSetBinaryMode' +-- h True@. +-- -- Example: -- -- >(h,pid) <- h_pipe_from $ exec "/usr/bin/foo" ["bar"] @@ -1240,7 +1334,7 @@ -- | Run an IO action in a separate process, and read its standard output, The output -- is read lazily, as the returned string is evaluated. The child's output along -- with its process ID are returned. --- +-- -- This forks a child process, which executes the specified action. The output -- of the child is read lazily through a pipe, which connncts to its standard -- output. In case the child replaces the process by calling an @exec@ variant, @@ -1261,17 +1355,17 @@ -- descriptor, even when the pipe is closed on the child side. When you do that -- repeatedly, you may run out of file descriptors. -- --- Unless you're sure that your program will reach the string's end, you should +-- Unless you're sure that your program will reach the string's end, you should -- take care for it explicitly, by doing something like this: -- -- >(output, pid) <- lazy_pipe_from (exec "\/usr\/bin\/foobar" []) -- >... --- >seq (length output) (return ()) +-- >seq (length output) (return ()) -- -- This will read the entire standard output of the child, even if it isn't -- needed. You can't cut the child process' output short, when you use --- @lazy_pipe_from@. If you need to do this, you should use @h_pipe_from@, which --- gives you the handle, which can then be closed by 'System.IO.hClose', even +-- @lazy_pipe_from@. If you need to do this, you should use @h_pipe_from@, which +-- gives you the handle, which can then be closed by 'System.IO.hClose', even -- if the child's output isn't completed: -- -- >(h, pid) <- h_pipe_from io @@ -1280,24 +1374,24 @@ -- >output <- hGetContents h -- >... -- >-- Not eveyting read yet, but cut io short. --- >hClose h +-- >hClose h -- > -- >-- Wait for io to finish, and detect errors -- >(Just ps) <- System.Posix.getProcessStatus True False pid -- >when (ps /= Exited ExitSuccess) $ -- > throw ps --- +-- -- When you close the handle before all data has been read, then the child gets -- a @SIGPIPE@ signal. --- +-- -- After all the output has been read, you should call @getProcessStatus@ on the -- child's process ID, in order to detect errors. Be aware that you must -- evaluate the whole string, before calling @getProcessStatus@ blockingly, or -- you'll get a deadlock. --- --- You won't get an exception, if the child action exits in a way which --- indicates an error. Errors occur asynchronously, when the output string is --- evaluated. You must detect errors by yourself, by calling +-- +-- You won't get an exception, if the child action exits in a way which +-- indicates an error. Errors occur asynchronously, when the output string is +-- evaluated. You must detect errors by yourself, by calling -- 'System.Posix.Process.getProcessStatus'. -- -- In case the action doesn't replace the child process with an external @@ -1317,7 +1411,24 @@ -- Unlike shells\' backquote feature, @lazy_pipe_from@ does not remove any trailing -- newline characters. The entire output of the action is returned. You might want -- to apply @chomp@ to the result. --- +-- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from the IO action's stdout, are converted from the system +-- character set to Unicode. The system character set is determined by the +-- environment variable @LANG@. If you need to read binary data from the forked +-- process, you should use h_pipe_from and set the returned handle to binary mode. +-- This is accomplished by @'hSetBinaryMode' h True@. Then you can lazily read +-- the output of the action from the handle. +-- +-- Example: Lazily read binary data from an IO action. Don't forget to collect +-- the child process later, using @'System.Posix.getProcessStatus' True False pid@. +-- +-- >(h, pid) <- h_pipe_from io +-- >hSetBinaryMode h True +-- >txt <- hGetContents h +-- >... +-- >(Just ps) <- System.Posix.getProcessStatus True False pid +-- -- See 'exec', 'pipe_to', 'pipe_from', 'h_pipe_from', 'lazy_pipe_from2', 'silently'. lazy_pipe_from :: IO a -- ^ Action to run as a separate process -> IO (String, ProcessID) -- ^ The action's lazy output and the process ID of the child process @@ -1327,11 +1438,10 @@ return (txt, pid) - -- | Run an IO action in a separate process, and read its standard error output, The output -- is read lazily, as the returned string is evaluated. The child's error output along -- with its process ID are returned. --- +-- -- This forks a child process, which executes the specified action. The error output -- of the child is read lazily through a pipe, which connncts to its standard error -- output. In case the child replaces the process by calling an @exec@ variant, @@ -1352,17 +1462,17 @@ -- descriptor, even when the pipe is closed on the child side. When you do that -- repeatedly, you may run out of file descriptors. -- --- Unless you're sure that your program will reach the string's end, you should +-- Unless you're sure that your program will reach the string's end, you should -- take care for it explicitly, by doing something like this: -- -- >(errmsg, pid) <- lazy_pipe_from2 (exec "/usr/bin/foobar" []) -- >... --- >seq (length errmsg) (return ()) +-- >seq (length errmsg) (return ()) -- -- This will read the entire standard error output of the child, even if it isn't -- needed. You can't cut the child process' output short, when you use --- @lazy_pipe_from@. If you need to do this, you should use @h_pipe_from@, which --- gives you the handle, which can then be closed by 'System.IO.hClose', even +-- @lazy_pipe_from@. If you need to do this, you should use @h_pipe_from@, which +-- gives you the handle, which can then be closed by 'System.IO.hClose', even -- if the child's output isn't completed: -- -- >(h, pid) <- h_pipe_from io @@ -1371,24 +1481,24 @@ -- >output <- hGetContents h -- >... -- >-- Not eveyting read yet, but cut io short. --- >hClose h +-- >hClose h -- > -- >-- Wait for io to finish, and detect errors -- >(Just ps) <- System.Posix.getProcessStatus True False pid -- >when (ps /= Exited ExitSuccess) $ -- > throw ps --- +-- -- When you close the handle before all data has been read, then the child gets -- a @SIGPIPE@ signal. --- +-- -- After all the output has been read, you should call @getProcessStatus@ on the -- child's process ID, in order to detect errors. Be aware that you must -- evaluate the whole string, before calling @getProcessStatus@ blockingly, or -- you'll get a deadlock. --- --- You won't get an exception, if the child action exits in a way which --- indicates an error. Errors occur asynchronously, when the output string is --- evaluated. You must detect errors by yourself, by calling +-- +-- You won't get an exception, if the child action exits in a way which +-- indicates an error. Errors occur asynchronously, when the output string is +-- evaluated. You must detect errors by yourself, by calling -- 'System.Posix.Process.getProcessStatus'. -- -- In case the action doesn't replace the child process with an external @@ -1406,10 +1516,34 @@ -- then properly terminated, such that no resources, which have been duplicated -- by the fork, cause problems. See "HsShellScript#subr" for details. -- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from stdin, is converted from the system character set to +-- Unicode. The system character set is determined by the environment variable +-- @LANG@. If you need to read binary data from the forked process, you can set +-- the returned handle to binary mode. This is accomplished by @'hSetBinaryMode' +-- h True@. +-- -- Unlike shells\' backquote feature, @lazy_pipe_from@ does not remove any trailing -- newline characters. The entire output of the action is returned. You might want -- to apply @chomp@ to the result. --- +-- +-- The pipe is set to /text mode/. This means that the Unicode characters in the +-- text, which is read from the IO action's stdout, are converted from the +-- system character set to Unicode. The system character set is determined by +-- the environment variable @LANG@. If you need to read binary data from the +-- forked process' standard error output, you should use h_pipe_from2 and set +-- the returned handle to binary mode. This is accomplished by @'hSetBinaryMode' +-- h True@. Then you can lazily read the output of the action from the handle. +-- +-- Example: Lazily read binary data from an IO action. Don't forget to collect +-- the child process later, using @'System.Posix.getProcessStatus' True False pid@. +-- +-- >(h, pid) <- h_pipe_from2 io +-- >hSetBinaryMode h True +-- >txt <- hGetContents h +-- >... +-- >(Just ps) <- System.Posix.getProcessStatus True False pid +-- -- See 'exec', 'pipe_to', 'pipe_from2', 'h_pipe_from2', 'lazy_pipe_from', 'silently'. lazy_pipe_from2 :: IO a -- ^ Action to run as a separate process -> IO (String, ProcessID) -- ^ The action's lazy output and the process ID of the child process @@ -1417,14 +1551,43 @@ (_, _, Just h, pid) <- pipe_fork_dup io False False True txt <- hGetContents h return (txt, pid) - + -- | Run an IO action as a separate process, and optionally connect to its --- @stdin@, its @stdout@ and its @stderr@ output with --- pipes. +-- @stdin@, its @stdout@ and its @stderr@ output with pipes. -- --- See 'pipe_from', 'pipe_from2', 'pipe_to'. +-- This forks a subprocess, which executes the specified action. The child\'s +-- @ProcessID@ is returned. Some of the action\'s standard handles are made to +-- connected to pipes, which the caller can use in order to communicate with the +-- new child process. Which, this is determined by the first three arguments. +-- +-- You get full control of the pipes, and of the forked process. But you +-- must cope with the child process by yourself. +-- +-- Errors in the child process can only be detected by examining its process +-- status (using 'System.Posix.Process.getProcessStatus'). If the child action +-- throws an exception, an error message is printed on @stderr@, and the child +-- process exits with a @ProcessStatus@ of @Exited (ExitFailure 1)@. The +-- following exceptions are understood, and result in corresponding messages: +-- @ArgError@, @ProcessStatus@, @RunError@, @IOError@ and @ExitCode@. Other +-- exceptions result in the generic message, as produced by @show@. +-- +-- Unless you replace the child process, calling an @exec@ variant, the child +-- should let the control flow leave the action normally. It is then properly +-- take care of. +-- +-- The pipes are set to /text mode/. When connecting to the child\'s @stdin@, +-- this means that the Unicode characters in the Haskell side text are converted +-- to the system character set. When reading from the child\'s @stdout@ or +-- @stderr@, the text is converted from the system character set to Unicode in +-- the Haskell-side strings. The system character set is determined by the +-- environment variable @LANG@. If you need to read or write binary data, then +-- this is no problem. Just call @'hSetBinaryMode' handle True@. This sets the +-- corresponding pipe to binary mode. +-- +-- See 'pipe_from', 'h_pipe_from', 'pipe_from2', 'h_pipe_from2', 'pipe_to', +-- 'h_pipe_to', 'lazy_pipe_from', 'lazy_pipe_from2' pipes :: IO a -- ^ Action to run in a new process -> Bool -- ^ Whether to make stdin pipe -> Bool -- ^ Whether to make stdout pipe @@ -2215,54 +2378,6 @@ instance Exception ProcessStatus - - -{- ALT: - ------------------------------------------------------------------------------------------------------------------------------------------------------- --- Getting the file descriptor which is encapsulated inside a handle - - --- This is a modified version of System.Posix.IO.handleToFd. The original function has the side effect of closing the handle. From the GHC --- documentation: --- --- "converting a Handle into an Fd effectively means --- letting go of the Handle; it is put into a closed --- state as a result." --- --- The modified version does the same, but doesn't close the handle. - -handleToFd_noclose :: Handle -- Handle, must be a @FileHandle@. Throws an @IOError@ when the handle is a @DuplexHandle@, or when the - -- handle doesn't incapsulate a file descriptor. - -> IO Fd -- The file descriptor inside of the handle. - -handleToFd_noclose h@(FileHandle _ m) = do - withHandle' "handleToFd_noclose" h m $ - handleToFd'_noclose h - -handleToFd_noclose h@(DuplexHandle _ r w) = - ioError (System.IO.Error.ioeSetErrorString - (System.IO.Error.mkIOError IllegalOperation "handleToFd_noclose" (Just h) Nothing) - "handle is a Duplex") - - -handleToFd'_noclose :: Handle -> Handle__ -> IO (Handle__, Fd) - -handleToFd'_noclose h h_@Handle__{haType=_, ..} = do - case cast haDevice of - Nothing -> ioError (System.IO.Error.ioeSetErrorString - (System.IO.Error.mkIOError IllegalOperation "handleToFd_noclose" (Just h) Nothing) - "handle is not a file descriptor") - Just fd -> do - -- Removed code (2 lines) which would close the handle. - return (Handle__{haType=ClosedHandle,..}, Fd (FD.fdFD fd)) --} - - - - - ------------------------------------------------------------------------------------------------------------------------------------------------------- #c /* diff --git a/test/Makefile b/test/Makefile new file mode 100644 --- /dev/null +++ b/test/Makefile @@ -0,0 +1,18 @@ +CFLAGS=-XDeriveDataTypeable + +% : %.o cteile.o ../dist/build/libHShsshellscript-3.3.0.a + ghc -o $@ $^ -package haskell2010 -package unix + +%.o : %.hs + ghc $(CFLAGS) -c $^ + +%.o : %.c + ghc $(CFLAGS) -c $^ + +%.hs : %.chs + -chmod u+w $@ + c2hs -o $@ $< + chmod u-w $@ + +clean :: + rm *.hi *.o *~ diff --git a/test/redirect.hs b/test/redirect.hs new file mode 100644 --- /dev/null +++ b/test/redirect.hs @@ -0,0 +1,6 @@ +import HsShellScript + +main = do + putStrLn "-1-" + runprog "/bin/echo" ["äöü"] ->- "/tmp/redirect" + putStrLn "-2-"