Graphics.UI.WXCore.Process

Process and stream wrappers.

Process

type OnReceive = String -> StreamStatus -> IO ()

Type of input receiver function.

type OnEndProcess = Int -> IO ()

Type of end-of-process event handler. Gets the exitcode as its argument.

processExecAsyncTimed :: Window a -> String -> Bool -> OnEndProcess -> OnReceive -> OnReceive -> IO (String -> IO StreamStatus, Process (), Int)

(processExecAsyncTimer command processOutputOnEnd onEndProcess onOutput onErrorOutput parent) starts the command asynchronously. The handler onEndProcess is called when the process terminates. onOutput receives the output from stdout, while onErrorOutput receives output from stderr. If processOutputOnEnd is True, the remaining output of a terminated process is processed (calling onOutput). The call returns a triple (send,process,pid): The send function is used to send input to the stdin pipe of the process. The process object is returned in process and the process identifier in pid.

Note: The method uses idle event timers to process the output channels. On many platforms this is uch more thrustworthy and robust than the processExecAsync that uses threads (which can cause all kinds of portability problems).

processExecAsync :: Window a -> String -> Int -> OnEndProcess -> OnReceive -> OnReceive -> IO (String -> IO (), Process (), Int)

deprecated: use processExecAsyncTimed instead (if possible). (processExecAsync command bufferSize onEndProcess onOutput onErrorOutput parent) starts the command asynchronously. The handler onEndProcess is called when the process terminates. onOutput receives the output from stdout, while onErrorOutput receives output from stderr. The bufferSize determines the intermediate buffer used to cache the output from those channels. The calls returns a triple (send,process,pid): The send function is used to send input to the stdin pipe of the process. The process object is returned in process and the process identifier in pid.

Streams

data StreamStatus

The status of a stream (see StreamBase)

Constructors

StreamOk

No error.

StreamEof

No more input.

StreamReadError

Read error.

StreamWriteError

Write error.

Instances

Eq StreamStatus

Show StreamStatus

streamBaseStatus :: StreamBase a -> IO StreamStatus

Return the status of the stream

Blocking IO

inputStreamGetContents :: InputStream a -> IO String

Get the entire contents of an input stream. The content is returned as a lazy stream (like hGetContents).

inputStreamGetContentsN :: InputStream a -> Int -> IO String

Get the entire contents of an input stream. The content is returned as a lazy stream (like hGetContents). The contents are returned in lazy batches, whose size is determined by the first parameter.

inputStreamGetLine :: InputStream a -> Int -> IO String

inputStreamGetLine s n reads a line of at most n characters from the input stream (potentially waiting for input). The function does automatic end-of-line conversion. If the line ends with \n, an entire line has been read, otherwise, either the maximum has been reached, or no more input was available.

inputStreamGetString :: InputStream a -> Int -> IO String

The expression (inputStreamGetString n input) reads a string of maximally n characters from input.

inputStreamGetChar :: InputStream a -> IO Char

Read a single character from the input. (equals inputStreamGetC)

outputStreamPutString :: OutputStream a -> String -> IO ()

Write a string to an output stream, potentially blocking until all output has been written.

Non-blocking IO

inputStreamGetLineNoWait :: InputStream a -> Int -> IO String

inputStreamGetLineNoWait stream n reads a line of at most n characters from the input stream in a non-blocking way. The function does automatic end-of-line conversion. If the line ends with \n, an entire line has been read, otherwise, either the maximum has been reached, or no more input was available.

inputStreamGetStringNoWait :: InputStream a -> Int -> IO String

inputStreamGetStringNoWait stream n reads a line of at most n characters from the input stream in a non-blocking way.

inputStreamGetCharNoWait :: InputStream a -> IO (Maybe Char)

Read a single character from the input, returning Nothing if no input was available (using inputStreamCanRead).

outputStreamPutStringNoWait :: OutputStream a -> String -> IO Int

Write a string to an output stream, returning the number of bytes actually written.