Safe Haskell | None |
---|---|
Language | Haskell2010 |
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 yourRIO
environment. SeemkProcessContext
. - Instead of using the
proc
function from System.Process.Typed for creating aProcessConfig
, use the locally definedproc
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
- 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
- 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
- doesExecutableExist :: (MonadIO m, MonadReader env m, HasProcessContext env) => String -> m Bool
- findExecutable :: (MonadIO m, MonadReader env m, HasProcessContext env) => String -> m (Either ProcessException FilePath)
- 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
- 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 # | |
Defined in RIO.Process |
class HasProcessContext env where Source #
Get the ProcessContext
from the environment.
Since: 0.0.3.0
processContextL :: Lens' env ProcessContext Source #
Instances
HasProcessContext LoggedProcessContext Source # | |
Defined in RIO.Process | |
HasProcessContext ProcessContext Source # | |
Defined in RIO.Process | |
HasProcessContext SimpleApp Source # | |
Defined in RIO.Prelude.Simple |
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 #
Load up an EnvOverride
from the standard environment.
modifyEnvVars :: MonadIO m => ProcessContext -> (EnvVars -> EnvVars) -> m ProcessContext Source #
Modify the environment variables of a ProcessContext
.
This will keep other settings unchanged, in particular 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 modifyEnvVarMap
to create a new ProcessContext
, and then
use it in the provided action.
Since: 0.0.3.0
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 #
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
:: (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 #
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 #
Same as withProcess_
, but generalized to MonadUnliftIO
.
Since: 0.0.3.0
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
Instances
HasLogFunc LoggedProcessContext Source # | |
Defined in RIO.Process | |
HasProcessContext LoggedProcessContext Source # | |
Defined in RIO.Process |
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
NoPathFound | |
ExecutableNotFound String [FilePath] | |
ExecutableNotFoundAt FilePath | |
PathsInvalidInPath [FilePath] |
Instances
Show ProcessException Source # | |
Defined in RIO.Process showsPrec :: Int -> ProcessException -> ShowS # show :: ProcessException -> String # showList :: [ProcessException] -> ShowS # | |
Exception ProcessException Source # | |
Defined in RIO.Process |
Utilities
:: (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
:: (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 executable.
Since: 0.0.3.0
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 useshell
.
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) | |
Defined in System.Process.Typed 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) | |
Defined in System.Process.Typed fromString :: String -> ProcessConfig stdin stdout stderr # | |
Display (ProcessConfig a b c) Source # | Since: 0.1.0.0 |
Defined in RIO.Prelude.Display 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) | |
Defined in System.Process.Typed 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 Since: typed-process-0.1.0.0 |
Defined in System.Process.Typed 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
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
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 #
setCreateNewConsole :: Bool -> ProcessConfig stdin stdout stderr -> ProcessConfig stdin stdout stderr #
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 thecreateProcess
function. This will be determined by theStdStream
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.
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
.
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
.
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
.
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
.
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_
.
Since: typed-process-0.1.0.0
ExitCodeException | |
|
Instances
Show ExitCodeException | |
Defined in System.Process.Typed showsPrec :: Int -> ExitCodeException -> ShowS # show :: ExitCodeException -> String # showList :: [ExitCodeException] -> ShowS # | |
Exception ExitCodeException | |
Defined in System.Process.Typed |
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
ByteStringOutputException SomeException (ProcessConfig () () ()) |
Instances
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