| Safe Haskell | Safe |
|---|---|
| Language | Haskell98 |
Data.Streaming.Process
Description
A full tutorial for this module is available on FP School of Haskell: https://www.fpcomplete.com/user/snoyberg/library-documentation/data-conduit-process.
Note that, while the tutorial covers Data.Conduit.Process, that module closely
follows the present one, and almost all concepts in the tutorial apply here.
- streamingProcess :: (MonadIO m, InputSource stdin, OutputSink stdout, OutputSink stderr) => CreateProcess -> m (stdin, stdout, stderr, StreamingProcessHandle)
- closeStreamingProcessHandle :: MonadIO m => StreamingProcessHandle -> m ()
- data Inherited = Inherited
- data ClosedStream = ClosedStream
- data UseProvidedHandle = UseProvidedHandle
- data StreamingProcessHandle
- waitForStreamingProcess :: MonadIO m => StreamingProcessHandle -> m ExitCode
- waitForStreamingProcessSTM :: StreamingProcessHandle -> STM ExitCode
- getStreamingProcessExitCode :: MonadIO m => StreamingProcessHandle -> m (Maybe ExitCode)
- getStreamingProcessExitCodeSTM :: StreamingProcessHandle -> STM (Maybe ExitCode)
- streamingProcessHandleRaw :: StreamingProcessHandle -> ProcessHandle
- streamingProcessHandleTMVar :: StreamingProcessHandle -> TMVar ExitCode
- class InputSource a
- class OutputSink a
- withCheckedProcess :: (InputSource stdin, OutputSink stderr, OutputSink stdout, MonadIO m) => CreateProcess -> (stdin -> stdout -> stderr -> m b) -> m b
- data ProcessExitedUnsuccessfully = ProcessExitedUnsuccessfully CreateProcess ExitCode
- module System.Process
Functions
streamingProcess :: (MonadIO m, InputSource stdin, OutputSink stdout, OutputSink stderr) => CreateProcess -> m (stdin, stdout, stderr, StreamingProcessHandle) Source #
The primary function for running a process. Note that, with the
exception of UseProvidedHandle, the values for std_in, std_out
and std_err will be ignored by this function.
Since 0.1.4
closeStreamingProcessHandle :: MonadIO m => StreamingProcessHandle -> m () Source #
Free any resources (e.g. Handles) acquired by a call to streamingProcess.
Since: 0.1.16
Specialized streaming types
data ClosedStream Source #
Close the stream with the child process.
Since 0.1.4
Constructors
| ClosedStream |
Instances
data UseProvidedHandle Source #
Use the Handle provided by the CreateProcess value. This would allow
you, for example, to open up a Handle to a file, set it as std_out, and
avoid any additional overhead of dealing with providing that data to your
process.
Since 0.1.4
Constructors
| UseProvidedHandle |
Process handle
data StreamingProcessHandle Source #
Wraps up the standard ProcessHandle to avoid the waitForProcess
deadlock. See the linked documentation from the module header for more
information.
Since 0.1.4
waitForStreamingProcess :: MonadIO m => StreamingProcessHandle -> m ExitCode Source #
Blocking call to wait for a process to exit.
Since 0.1.4
waitForStreamingProcessSTM :: StreamingProcessHandle -> STM ExitCode Source #
STM version of waitForStreamingProcess.
Since 0.1.4
getStreamingProcessExitCode :: MonadIO m => StreamingProcessHandle -> m (Maybe ExitCode) Source #
Non-blocking call to check for a process exit code.
Since 0.1.4
getStreamingProcessExitCodeSTM :: StreamingProcessHandle -> STM (Maybe ExitCode) Source #
STM version of getStreamingProcessExitCode.
Since 0.1.4
streamingProcessHandleRaw :: StreamingProcessHandle -> ProcessHandle Source #
Get the raw ProcessHandle from a StreamingProcessHandle. Note that
you should avoid using this to get the process exit code, and instead
use the provided functions.
Since 0.1.4
streamingProcessHandleTMVar :: StreamingProcessHandle -> TMVar ExitCode Source #
Get the TMVar storing the process exit code. In general, one of the
above functions should be used instead to avoid accidentally corrupting the variable's state..
Since 0.1.4
Type classes
class InputSource a Source #
Class for all things which can be used to provide standard input.
Since 0.1.4
Minimal complete definition
class OutputSink a Source #
Class for all things which can be used to consume standard output or error.
Since 0.1.4
Minimal complete definition
Checked processes
withCheckedProcess :: (InputSource stdin, OutputSink stderr, OutputSink stdout, MonadIO m) => CreateProcess -> (stdin -> stdout -> stderr -> m b) -> m b Source #
Run a process and supply its streams to the given callback function. After
the callback completes, wait for the process to complete and check its exit
code. If the exit code is not a success, throw a
ProcessExitedUnsuccessfully.
NOTE: This function does not kill the child process or ensure
resources are cleaned up in the event of an exception from the
provided function. For that, please use withCheckedProcessCleanup
from the conduit-extra package.
Since 0.1.7
data ProcessExitedUnsuccessfully Source #
Indicates that a process exited with an non-success exit code.
Since 0.1.7
Constructors
| ProcessExitedUnsuccessfully CreateProcess ExitCode |
Reexport
module System.Process