Safe Haskell	None
Language	Haskell2010

RIO.Process

Contents

Process context
- Lenses
- Actions
Configuring
Spawning (run child process)
Exec (replacing current process)
Environment helper
Exceptions
Utilities
Reexports

Description

Interacting with external processes.

This module provides a layer on top of System.Process.Typed, with the following additions:

For efficiency, it will cache PATH lookups.
For convenience, you can set the working directory and env vars overrides in a RIO environment instead of on the individual calls to the process.
Built-in support for logging at the debug level.

In order to switch over to this API, the main idea is:

Like most of the rio library, you need to create an environment value (this time ProcessContext), and include it in your RIO environment. See mkProcessContext.
Instead of using the proc function from System.Process.Typed for creating a ProcessConfig, use the locally defined proc function, which will handle overriding environment variables, looking up paths, performing logging, etc.

Once you have your ProcessConfig, use the standard functions from Typed (reexported here for convenient) for running the ProcessConfig.

Since: 0.0.3.0

Synopsis

data ProcessContext
class HasProcessContext env where
- processContextL :: Lens' env ProcessContext
type EnvVars = Map Text Text
mkProcessContext :: MonadIO m => EnvVars -> m ProcessContext
mkDefaultProcessContext :: MonadIO m => m ProcessContext
modifyEnvVars :: MonadIO m => ProcessContext -> (EnvVars -> EnvVars) -> m ProcessContext
withModifyEnvVars :: (HasProcessContext env, MonadReader env m, MonadIO m) => (EnvVars -> EnvVars) -> m a -> m a
lookupEnvFromContext :: (MonadReader env m, HasProcessContext env) => Text -> m (Maybe Text)
withWorkingDir :: (HasProcessContext env, MonadReader env m, MonadIO m) => FilePath -> m a -> m a
workingDirL :: HasProcessContext env => Lens' env (Maybe FilePath)
envVarsL :: HasProcessContext env => SimpleGetter env EnvVars
envVarsStringsL :: HasProcessContext env => SimpleGetter env [(String, String)]
exeSearchPathL :: HasProcessContext env => SimpleGetter env [FilePath]
resetExeCache :: (MonadIO m, MonadReader env m, HasProcessContext env) => m ()
proc :: (HasProcessContext env, HasLogFunc env, MonadReader env m, MonadIO m, HasCallStack) => FilePath -> [String] -> (ProcessConfig () () () -> m a) -> m a
withProcess :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
withProcess_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
withProcessWait :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
withProcessWait_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
withProcessTerm :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
withProcessTerm_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a
exec :: (HasProcessContext env, HasLogFunc env) => String -> [String] -> RIO env b
execSpawn :: (HasProcessContext env, HasLogFunc env) => String -> [String] -> RIO env a
data LoggedProcessContext = LoggedProcessContext ProcessContext LogFunc
withProcessContextNoLogging :: MonadIO m => RIO LoggedProcessContext a -> m a
data ProcessException
- = NoPathFound
- | ExecutableNotFound String [FilePath]
- | ExecutableNotFoundAt FilePath
- | PathsInvalidInPath [FilePath]
doesExecutableExist :: (MonadIO m, MonadReader env m, HasProcessContext env) => String -> m Bool
findExecutable :: (MonadIO m, MonadReader env m, HasProcessContext env) => String -> m (Either ProcessException FilePath)
exeExtensions :: (MonadIO m, MonadReader env m, HasProcessContext env) => m [String]
augmentPath :: [FilePath] -> Maybe Text -> Either ProcessException Text
augmentPathMap :: [FilePath] -> EnvVars -> Either ProcessException EnvVars
showProcessArgDebug :: String -> Text
data ProcessConfig stdin stdout stderr
data StreamSpec (streamType :: StreamType) a
data StreamType
- = STInput
- | STOutput
data Process stdin stdout stderr
setStdin :: StreamSpec STInput stdin -> ProcessConfig stdin0 stdout stderr -> ProcessConfig stdin stdout stderr
setStdout :: StreamSpec STOutput stdout -> ProcessConfig stdin stdout0 stderr -> ProcessConfig stdin stdout stderr
setStderr :: StreamSpec STOutput stderr -> ProcessConfig stdin stdout stderr0 -> ProcessConfig stdin stdout stderr
setCloseFds :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setCreateGroup :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setDelegateCtlc :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setDetachConsole :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setCreateNewConsole :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setNewSession :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setChildGroup :: GroupID -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
setChildUser :: UserID -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr
mkStreamSpec :: StdStream -> (ProcessConfig () () () -> Maybe Handle -> IO (a, IO ())) -> StreamSpec streamType a
inherit :: StreamSpec anyStreamType ()
closed :: StreamSpec anyStreamType ()
byteStringInput :: ByteString -> StreamSpec STInput ()
byteStringOutput :: StreamSpec STOutput (STM ByteString)
createPipe :: StreamSpec anyStreamType Handle
useHandleOpen :: Handle -> StreamSpec anyStreamType ()
useHandleClose :: Handle -> StreamSpec anyStreamType ()
startProcess :: MonadIO m => ProcessConfig stdin stdout stderr -> m (Process stdin stdout stderr)
stopProcess :: MonadIO m => Process stdin stdout stderr -> m ()
readProcess :: MonadIO m => ProcessConfig stdin stdoutIgnored stderrIgnored -> m (ExitCode, ByteString, ByteString)
readProcess_ :: MonadIO m => ProcessConfig stdin stdoutIgnored stderrIgnored -> m (ByteString, ByteString)
runProcess :: MonadIO m => ProcessConfig stdin stdout stderr -> m ExitCode
runProcess_ :: MonadIO m => ProcessConfig stdin stdout stderr -> m ()
readProcessStdout :: MonadIO m => ProcessConfig stdin stdoutIgnored stderr -> m (ExitCode, ByteString)
readProcessStdout_ :: MonadIO m => ProcessConfig stdin stdoutIgnored stderr -> m ByteString
readProcessStderr :: MonadIO m => ProcessConfig stdin stdout stderrIgnored -> m (ExitCode, ByteString)
readProcessStderr_ :: MonadIO m => ProcessConfig stdin stdout stderrIgnored -> m ByteString
waitExitCode :: MonadIO m => Process stdin stdout stderr -> m ExitCode
waitExitCodeSTM :: Process stdin stdout stderr -> STM ExitCode
getExitCode :: MonadIO m => Process stdin stdout stderr -> m (Maybe ExitCode)
getExitCodeSTM :: Process stdin stdout stderr -> STM (Maybe ExitCode)
checkExitCode :: MonadIO m => Process stdin stdout stderr -> m ()
checkExitCodeSTM :: Process stdin stdout stderr -> STM ()
getStdin :: Process stdin stdout stderr -> stdin
getStdout :: Process stdin stdout stderr -> stdout
getStderr :: Process stdin stdout stderr -> stderr
data ExitCodeException = ExitCodeException {
- eceExitCode :: ExitCode
- eceProcessConfig :: ProcessConfig () () ()
- eceStdout :: ByteString
- eceStderr :: ByteString
}
data ByteStringOutputException = ByteStringOutputException SomeException (ProcessConfig () () ())
unsafeProcessHandle :: Process stdin stdout stderr -> ProcessHandle

Process context

data ProcessContext Source #

Context in which to run processes.

Since: 0.0.3.0

Instances

HasProcessContext ProcessContext Source #
Instance details Defined in RIO.Process Methods processContextL :: Lens' ProcessContext ProcessContext Source #

class HasProcessContext env where Source #

Get the ProcessContext from the environment.

Since: 0.0.3.0

Methods

processContextL :: Lens' env ProcessContext Source #

Instances

HasProcessContext LoggedProcessContext Source #
Instance details Defined in RIO.Process Methods processContextL :: Lens' LoggedProcessContext ProcessContext Source #
HasProcessContext ProcessContext Source #
Instance details Defined in RIO.Process Methods processContextL :: Lens' ProcessContext ProcessContext Source #
HasProcessContext SimpleApp Source #
Instance details Defined in RIO.Prelude.Simple Methods processContextL :: Lens' SimpleApp ProcessContext Source #

type EnvVars = Map Text Text Source #

The environment variable map

Since: 0.0.3.0

mkProcessContext :: MonadIO m => EnvVars -> m ProcessContext Source #

Create a new ProcessContext from the given environment variable map.

Since: 0.0.3.0

mkDefaultProcessContext :: MonadIO m => m ProcessContext Source #

Same as mkProcessContext but uses the system environment (from getEnvironment).

Since: 0.0.3.0

modifyEnvVars :: MonadIO m => ProcessContext -> (EnvVars -> EnvVars) -> m ProcessContext Source #

Modify the environment variables of a ProcessContext. This will not change the working directory.

Note that this requires MonadIO, as it will create a new IORef for the cache.

Since: 0.0.3.0

withModifyEnvVars :: (HasProcessContext env, MonadReader env m, MonadIO m) => (EnvVars -> EnvVars) -> m a -> m a Source #

Use modifyEnvVars to create a new ProcessContext, and then use it in the provided action.

Since: 0.0.3.0

lookupEnvFromContext :: (MonadReader env m, HasProcessContext env) => Text -> m (Maybe Text) Source #

Look into the ProcessContext and return the specified environmet variable if one is available.

Since: 0.1.14.0

withWorkingDir :: (HasProcessContext env, MonadReader env m, MonadIO m) => FilePath -> m a -> m a Source #

Set the working directory to be used by child processes.

Since: 0.0.3.0

Lenses

workingDirL :: HasProcessContext env => Lens' env (Maybe FilePath) Source #

Override the working directory processes run in. Nothing means the current process's working directory.

Since: 0.0.3.0

envVarsL :: HasProcessContext env => SimpleGetter env EnvVars Source #

Get the environment variables. We cannot provide a Lens here, since updating the environment variables requires an IO action to allocate a new IORef for holding the executable path cache.

Since: 0.0.3.0

envVarsStringsL :: HasProcessContext env => SimpleGetter env [(String, String)] Source #

Get the EnvVars as an associated list of Strings.

Useful for interacting with other libraries.

Since: 0.0.3.0

exeSearchPathL :: HasProcessContext env => SimpleGetter env [FilePath] Source #

Get the list of directories searched for executables (the PATH).

Similar to envVarMapL, this cannot be a full Lens.

Since: 0.0.3.0

Actions

resetExeCache :: (MonadIO m, MonadReader env m, HasProcessContext env) => m () Source #

Reset the executable cache.

Since: 0.0.3.0

Configuring

proc Source #

Arguments

:: (HasProcessContext env, HasLogFunc env, MonadReader env m, MonadIO m, HasCallStack)
=> FilePath	command to run
-> [String]	command line arguments
-> (ProcessConfig () () () -> m a)
-> m a

Provide a ProcessConfig based on the ProcessContext in scope. Deals with resolving the full path, setting the child process's environment variables, setting the working directory, and wrapping the call with withProcessTimeLog for debugging output.

This is intended to be analogous to the proc function provided by the System.Process.Typed module, but has a different type signature to (1) allow it to perform IO actions for looking up paths, and (2) allow logging and timing of the running action.

Since: 0.0.3.0

Spawning (run child process)

withProcess :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Deprecated: Please consider using withProcessWait, or instead use withProcessTerm

Same as withProcess, but generalized to MonadUnliftIO.

Since: 0.0.3.0

withProcess_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Deprecated: Please consider using withProcessWait, or instead use withProcessTerm

Same as withProcess_, but generalized to MonadUnliftIO.

Since: 0.0.3.0

withProcessWait :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Same as withProcessWait, but generalized to MonadUnliftIO.

Since: 0.1.10.0

withProcessWait_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Same as withProcessWait_, but generalized to MonadUnliftIO.

Since: 0.1.10.0

withProcessTerm :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Same as withProcessTerm, but generalized to MonadUnliftIO.

Since: 0.1.10.0

withProcessTerm_ :: MonadUnliftIO m => ProcessConfig stdin stdout stderr -> (Process stdin stdout stderr -> m a) -> m a Source #

Same as withProcessTerm_, but generalized to MonadUnliftIO.

Since: 0.1.10.0

Exec (replacing current process)

exec :: (HasProcessContext env, HasLogFunc env) => String -> [String] -> RIO env b Source #

Execute a process within the configured environment.

Execution will not return, because either:

1) On non-windows, execution is taken over by execv of the sub-process. This allows signals to be propagated (#527)

2) On windows, an ExitCode exception will be thrown.

Since: 0.0.3.0

execSpawn :: (HasProcessContext env, HasLogFunc env) => String -> [String] -> RIO env a Source #

Like exec, but does not use execv on non-windows. This way, there is a sub-process, which is helpful in some cases (https://github.com/commercialhaskell/stack/issues/1306).

This function only exits by throwing ExitCode.

Since: 0.0.3.0

Environment helper

data LoggedProcessContext Source #

A convenience environment combining a LogFunc and a ProcessContext

Since: 0.0.3.0

Constructors

LoggedProcessContext ProcessContext LogFunc

Instances

HasLogFunc LoggedProcessContext Source #
Instance details Defined in RIO.Process Methods logFuncL :: Lens' LoggedProcessContext LogFunc Source #
HasProcessContext LoggedProcessContext Source #
Instance details Defined in RIO.Process Methods processContextL :: Lens' LoggedProcessContext ProcessContext Source #

withProcessContextNoLogging :: MonadIO m => RIO LoggedProcessContext a -> m a Source #

Run an action using a LoggedProcessContext with default settings and no logging.

Since: 0.0.3.0

Exceptions

data ProcessException Source #

Exception type which may be generated in this module.

NOTE Other exceptions may be thrown by underlying libraries!

Since: 0.0.3.0

Constructors

NoPathFound
ExecutableNotFound String [FilePath]
ExecutableNotFoundAt FilePath
PathsInvalidInPath [FilePath]

Instances

Show ProcessException Source #
Instance details Defined in RIO.Process Methods showsPrec :: Int -> ProcessException -> ShowS # show :: ProcessException -> String # showList :: [ProcessException] -> ShowS #
Exception ProcessException Source #
Instance details Defined in RIO.Process Methods toException :: ProcessException -> SomeException # fromException :: SomeException -> Maybe ProcessException # displayException :: ProcessException -> String #

Utilities

doesExecutableExist Source #

Arguments

:: (MonadIO m, MonadReader env m, HasProcessContext env)
=> String	Name of executable
-> m Bool

Check if the given executable exists on the given PATH.

Since: 0.0.3.0

findExecutable Source #

Arguments

:: (MonadIO m, MonadReader env m, HasProcessContext env)
=> String	Name of executable
-> m (Either ProcessException FilePath)	Full path to that executable on success

Find the complete path for the given executable name.

On POSIX systems, filenames that match but are not exectuables are excluded.

On Windows systems, the executable names tried, in turn, are the supplied name (only if it has an extension) and that name extended by each of the exeExtensions. Also, this function may behave differently from findExecutable. The latter excludes as executables filenames without a .bat, .cmd, .com or .exe extension (case-insensitive).

Since: 0.0.3.0

exeExtensions :: (MonadIO m, MonadReader env m, HasProcessContext env) => m [String] Source #

Get the filename extensions for executable files, including the dot (if any).

On POSIX systems, this is [""].

On Windows systems, the list is determined by the value of the PATHEXT environment variable, if it present in the environment. If the variable is absent, this is its default value on a Windows system. This function may, therefore, behave differently from exeExtension, which returns only ".exe".

Since: 0.1.13.0

augmentPath :: [FilePath] -> Maybe Text -> Either ProcessException Text Source #

Augment the PATH environment variable with the given extra paths.

Since: 0.0.3.0

augmentPathMap :: [FilePath] -> EnvVars -> Either ProcessException EnvVars Source #

Apply augmentPath on the PATH value in the given EnvVars.

Since: 0.0.3.0

showProcessArgDebug :: String -> Text Source #

Show a process arg including speechmarks when necessary. Just for debugging purposes, not functionally important.

Since: 0.0.3.0

Reexports

data ProcessConfig stdin stdout stderr #

An abstract configuration for a process, which can then be launched into an actual running Process. Takes three type parameters, providing the types of standard input, standard output, and standard error, respectively.

There are three ways to construct a value of this type:

With the proc smart constructor, which takes a command name and a list of arguments.
With the shell smart constructor, which takes a shell string
With the IsString instance via OverloadedStrings. If you provide it a string with no spaces (e.g., "date"), it will treat it as a raw command with no arguments (e.g., proc "date" []). If it has spaces, it will use shell.

In all cases, the default for all three streams is to inherit the streams from the parent process. For other settings, see the setters below for default values.

Since: typed-process-0.1.0.0

Instances

Show (ProcessConfig stdin stdout stderr)
Instance details Defined in System.Process.Typed Methods showsPrec :: Int -> ProcessConfig stdin stdout stderr -> ShowS # show :: ProcessConfig stdin stdout stderr -> String # showList :: [ProcessConfig stdin stdout stderr] -> ShowS #
(stdin ~ (), stdout ~ (), stderr ~ ()) => IsString (ProcessConfig stdin stdout stderr)
Instance details Defined in System.Process.Typed Methods fromString :: String -> ProcessConfig stdin stdout stderr #
Display (ProcessConfig a b c) Source #	Since: 0.1.0.0
Instance details Defined in RIO.Prelude.Display Methods display :: ProcessConfig a b c -> Utf8Builder Source # textDisplay :: ProcessConfig a b c -> Text Source #

data StreamSpec (streamType :: StreamType) a #

A specification for how to create one of the three standard child streams. See examples below.

Since: typed-process-0.1.0.0

Instances

Functor (StreamSpec streamType)
Instance details Defined in System.Process.Typed Methods fmap :: (a -> b) -> StreamSpec streamType a -> StreamSpec streamType b # (<$) :: a -> StreamSpec streamType b -> StreamSpec streamType a #
(streamType ~ STInput, res ~ ()) => IsString (StreamSpec streamType res)	This instance uses `byteStringInput` to convert a raw string into a stream of input for a child process. Since: typed-process-0.1.0.0
Instance details Defined in System.Process.Typed Methods fromString :: String -> StreamSpec streamType res #

data StreamType #

Whether a stream is an input stream or output stream. Note that this is from the perspective of the child process, so that a child's standard input stream is an STInput, even though the parent process will be writing to it.

Since: typed-process-0.1.0.0

Constructors

STInput
STOutput

data Process stdin stdout stderr #

A running process. The three type parameters provide the type of the standard input, standard output, and standard error streams.

Since: typed-process-0.1.0.0

Instances

Show (Process stdin stdout stderr)
Instance details Defined in System.Process.Typed Methods showsPrec :: Int -> Process stdin stdout stderr -> ShowS # show :: Process stdin stdout stderr -> String # showList :: [Process stdin stdout stderr] -> ShowS #

setStdin :: StreamSpec STInput stdin -> ProcessConfig stdin0 stdout stderr -> ProcessConfig stdin stdout stderr #

Set the child's standard input stream to the given StreamSpec.

Default: inherit

Since: typed-process-0.1.0.0

setStdout :: StreamSpec STOutput stdout -> ProcessConfig stdin stdout0 stderr -> ProcessConfig stdin stdout stderr #

Set the child's standard output stream to the given StreamSpec.

Default: inherit

Since: typed-process-0.1.0.0

setStderr :: StreamSpec STOutput stderr -> ProcessConfig stdin stdout stderr0 -> ProcessConfig stdin stdout stderr #

Set the child's standard error stream to the given StreamSpec.

Default: inherit

Since: typed-process-0.1.0.0

setCloseFds :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Should we close all file descriptors besides stdin, stdout, and stderr? See close_fds for more information.

Default: False

Since: typed-process-0.1.0.0

setCreateGroup :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Should we create a new process group?

Default: False

Since: typed-process-0.1.0.0

setDelegateCtlc :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Delegate handling of Ctrl-C to the child. For more information, see delegate_ctlc.

Default: False

Since: typed-process-0.1.0.0

setDetachConsole :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Detach console on Windows, see detach_console.

Default: False

Since: typed-process-0.1.0.0

setCreateNewConsole :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Create new console on Windows, see create_new_console.

Default: False

Since: typed-process-0.1.0.0

setNewSession :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Set a new session with the POSIX setsid syscall, does nothing on non-POSIX. See new_session.

Default: False

Since: typed-process-0.1.0.0

setChildGroup :: GroupID -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Set the child process's group ID with the POSIX setgid syscall, does nothing on non-POSIX. See child_group.

Default: False

Since: typed-process-0.1.0.0

setChildUser :: UserID -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #

Set the child process's user ID with the POSIX setuid syscall, does nothing on non-POSIX. See child_user.

Default: False

Since: typed-process-0.1.0.0

mkStreamSpec :: StdStream -> (ProcessConfig () () () -> Maybe Handle -> IO (a, IO ())) -> StreamSpec streamType a #

Create a new StreamSpec from the given StdStream and a helper function. This function:

Takes as input the raw Maybe Handle returned by the createProcess function. This will be determined by the StdStream argument.
Returns the actual stream value a, as well as a cleanup
function to be run when calling stopProcess.

Since: typed-process-0.1.0.0

inherit :: StreamSpec anyStreamType () #

A stream spec which simply inherits the stream of the parent process.

Since: typed-process-0.1.0.0

closed :: StreamSpec anyStreamType () #

A stream spec which will close the stream for the child process. You usually do not want to use this, as it will leave the corresponding file descriptor unassigned and hence available for re-use in the child process. Prefer nullStream unless you're certain you want this behavior.

Since: typed-process-0.1.0.0

byteStringInput :: ByteString -> StreamSpec STInput () #

An input stream spec which sets the input to the given ByteString. A separate thread will be forked to write the contents to the child process.

Since: typed-process-0.1.0.0

byteStringOutput :: StreamSpec STOutput (STM ByteString) #

Capture the output of a process in a ByteString.

This function will fork a separate thread to consume all input from the process, and will only make the results available when the underlying Handle is closed. As this is provided as an STM action, you can either check if the result is available, or block until it's ready.

In the event of any exception occurring when reading from the Handle, the STM action will throw a ByteStringOutputException.

Since: typed-process-0.1.0.0

createPipe :: StreamSpec anyStreamType Handle #

Create a new pipe between this process and the child, and return a Handle to communicate with the child.

Since: typed-process-0.1.0.0

useHandleOpen :: Handle -> StreamSpec anyStreamType () #

Use the provided Handle for the child process, and when the process exits, do not close it. This is useful if, for example, you want to have multiple processes write to the same log file sequentially.

Since: typed-process-0.1.0.0

useHandleClose :: Handle -> StreamSpec anyStreamType () #

Use the provided Handle for the child process, and when the process exits, close it. If you have no reason to keep the Handle open, you should use this over useHandleOpen.

Since: typed-process-0.1.0.0

startProcess :: MonadIO m => ProcessConfig stdin stdout stderr -> m (Process stdin stdout stderr) #

Launch a process based on the given ProcessConfig. You should ensure that you close stopProcess on the result. It's usually better to use one of the functions in this module which ensures stopProcess is called, such as withProcess.

Since: typed-process-0.1.0.0

stopProcess :: MonadIO m => Process stdin stdout stderr -> m () #

Close a process and release any resources acquired. This will ensure terminateProcess is called, wait for the process to actually exit, and then close out resources allocated for the streams. In the event of any cleanup exceptions being thrown this will throw an exception.

Since: typed-process-0.1.0.0

readProcess :: MonadIO m => ProcessConfig stdin stdoutIgnored stderrIgnored -> m (ExitCode, ByteString, ByteString) #

Run a process, capture its standard output and error as a ByteString, wait for it to complete, and then return its exit code, output, and error.

Note that any previously used setStdout or setStderr will be overridden.

Since: typed-process-0.1.0.0

readProcess_ :: MonadIO m => ProcessConfig stdin stdoutIgnored stderrIgnored -> m (ByteString, ByteString) #

Same as readProcess, but instead of returning the ExitCode, checks it with checkExitCode.

Exceptions thrown by this function will include stdout and stderr.

Since: typed-process-0.1.0.0

runProcess :: MonadIO m => ProcessConfig stdin stdout stderr -> m ExitCode #

Run the given process, wait for it to exit, and returns its ExitCode.

Since: typed-process-0.1.0.0

runProcess_ :: MonadIO m => ProcessConfig stdin stdout stderr -> m () #

Same as runProcess, but instead of returning the ExitCode, checks it with checkExitCode.

Since: typed-process-0.1.0.0

readProcessStdout :: MonadIO m => ProcessConfig stdin stdoutIgnored stderr -> m (ExitCode, ByteString) #

Same as readProcess, but only read the stdout of the process. Original settings for stderr remain.

Since: typed-process-0.2.1.0

readProcessStdout_ :: MonadIO m => ProcessConfig stdin stdoutIgnored stderr -> m ByteString #

Same as readProcessStdout, but instead of returning the ExitCode, checks it with checkExitCode.

Exceptions thrown by this function will include stdout.

Since: typed-process-0.2.1.0

readProcessStderr :: MonadIO m => ProcessConfig stdin stdout stderrIgnored -> m (ExitCode, ByteString) #

Same as readProcess, but only read the stderr of the process. Original settings for stdout remain.

Since: typed-process-0.2.1.0

readProcessStderr_ :: MonadIO m => ProcessConfig stdin stdout stderrIgnored -> m ByteString #

Same as readProcessStderr, but instead of returning the ExitCode, checks it with checkExitCode.

Exceptions thrown by this function will include stderr.

Since: typed-process-0.2.1.0

waitExitCode :: MonadIO m => Process stdin stdout stderr -> m ExitCode #

Wait for the process to exit and then return its ExitCode.

Since: typed-process-0.1.0.0

waitExitCodeSTM :: Process stdin stdout stderr -> STM ExitCode #

Same as waitExitCode, but in STM.

Since: typed-process-0.1.0.0

getExitCode :: MonadIO m => Process stdin stdout stderr -> m (Maybe ExitCode) #

Check if a process has exited and, if so, return its ExitCode.

Since: typed-process-0.1.0.0

getExitCodeSTM :: Process stdin stdout stderr -> STM (Maybe ExitCode) #

Same as getExitCode, but in STM.

Since: typed-process-0.1.0.0

checkExitCode :: MonadIO m => Process stdin stdout stderr -> m () #

Wait for a process to exit, and ensure that it exited successfully. If not, throws an ExitCodeException.

Exceptions thrown by this function will not include stdout or stderr (This prevents unbounded memory usage from reading them into memory). However, some callers such as readProcess_ catch the exception, add the stdout and stderr, and rethrow.

Since: typed-process-0.1.0.0

checkExitCodeSTM :: Process stdin stdout stderr -> STM () #

Same as checkExitCode, but in STM.

Since: typed-process-0.1.0.0

getStdin :: Process stdin stdout stderr -> stdin #

Get the child's standard input stream value.

Since: typed-process-0.1.0.0

getStdout :: Process stdin stdout stderr -> stdout #

Get the child's standard output stream value.

Since: typed-process-0.1.0.0

getStderr :: Process stdin stdout stderr -> stderr #

Get the child's standard error stream value.

Since: typed-process-0.1.0.0

data ExitCodeException #

Exception thrown by checkExitCode in the event of a non-success exit code. Note that checkExitCode is called by other functions as well, like runProcess_ or readProcess_.

Note that several functions that throw an ExitCodeException intentionally do not populate eceStdout or eceStderr. This prevents unbounded memory usage for large stdout and stderrs.

Since: typed-process-0.1.0.0

Constructors

ExitCodeException
Fields eceExitCode :: ExitCode eceProcessConfig :: ProcessConfig () () () eceStdout :: ByteString eceStderr :: ByteString

Instances

Show ExitCodeException
Instance details Defined in System.Process.Typed Methods showsPrec :: Int -> ExitCodeException -> ShowS # show :: ExitCodeException -> String # showList :: [ExitCodeException] -> ShowS #
Exception ExitCodeException
Instance details Defined in System.Process.Typed Methods toException :: ExitCodeException -> SomeException # fromException :: SomeException -> Maybe ExitCodeException # displayException :: ExitCodeException -> String #

data ByteStringOutputException #

Wrapper for when an exception is thrown when reading from a child process, used by byteStringOutput.

Since: typed-process-0.1.0.0

Constructors

ByteStringOutputException SomeException (ProcessConfig () () ())

Instances

Show ByteStringOutputException
Instance details Defined in System.Process.Typed Methods showsPrec :: Int -> ByteStringOutputException -> ShowS # show :: ByteStringOutputException -> String # showList :: [ByteStringOutputException] -> ShowS #
Exception ByteStringOutputException
Instance details Defined in System.Process.Typed Methods toException :: ByteStringOutputException -> SomeException # fromException :: SomeException -> Maybe ByteStringOutputException # displayException :: ByteStringOutputException -> String #

unsafeProcessHandle :: Process stdin stdout stderr -> ProcessHandle #

Take ProcessHandle out of the Process. This method is needed in cases one need to use low level functions from the process package. Use cases for this method are:

Send a special signal to the process.
Terminate the process group instead of terminating single process.
Use platform specific API on the underlying process.

This method is considered unsafe because the actions it performs on the underlying process may overlap with the functionality that typed-process provides. For example the user should not call waitForProcess on the process handle as eiter waitForProcess or stopProcess will lock. Additionally, even if process was terminated by the terminateProcess or by sending signal, stopProcess should be called either way in order to cleanup resources allocated by the typed-process.

Since: typed-process-0.1.1