juce::ChildProcess Class Reference

Detailed Description

Launches and monitors a child process.

This class lets you launch an executable, and read its output. You can also use it to check whether the child process has finished.

Public Types
enum	StreamFlags { wantStdOut = 1 , wantStdErr = 2 }
	These flags are used by the start() methods. More...

Public Member Functions
	ChildProcess ()
	Creates a process object.
	~ChildProcess ()
	Destructor.
bool	start (const String &command, int streamFlags=wantStdOut|wantStdErr)
	Attempts to launch a child process command.
bool	start (const StringArray &arguments, int streamFlags=wantStdOut|wantStdErr)
	Attempts to launch a child process command.
bool	isRunning () const
	Returns true if the child process is alive.
int	readProcessOutput (void *destBuffer, int numBytesToRead)
	Attempts to read some output from the child process.
String	readAllProcessOutput ()
	Blocks until the process has finished, and then returns its complete output as a string.
bool	waitForProcessToFinish (int timeoutMs) const
	Blocks until the process is no longer running.
uint32	getExitCode () const
	If the process has finished, this returns its exit code.
bool	kill ()
	Attempts to kill the child process.

Member Enums

StreamFlags

enum juce::ChildProcess::StreamFlags

These flags are used by the start() methods.

Enumerator
wantStdOut
wantStdErr

Constructors and Destructors

ChildProcess()

juce::ChildProcess::ChildProcess

(

)

Creates a process object.

To actually launch the process, use start().

Referenced by kill().

~ChildProcess()

juce::ChildProcess::~ChildProcess

(

)

Destructor.

Note that deleting this object won't terminate the child process.

Member Functions

start() [1/2]

bool juce::ChildProcess::start	(	const String &	command,
		int	streamFlags = wantStdOut|wantStdErr )

Attempts to launch a child process command.

The command should be the name of the executable file, followed by any arguments that are required. If the process has already been launched, this will launch it again. If a problem occurs, the method will return false. The streamFlags is a combinations of values to indicate which of the child's output streams should be read and returned by readProcessOutput().

References command, wantStdErr, and wantStdOut.

start() [2/2]

bool juce::ChildProcess::start	(	const StringArray &	arguments,
		int	streamFlags = wantStdOut|wantStdErr )

Attempts to launch a child process command.

The first argument should be the name of the executable file, followed by any other arguments that are needed. If the process has already been launched, this will launch it again. If a problem occurs, the method will return false. The streamFlags is a combinations of values to indicate which of the child's output streams should be read and returned by readProcessOutput().

References wantStdErr, and wantStdOut.

isRunning()

bool juce::ChildProcess::isRunning

(

)

const

Returns true if the child process is alive.

readProcessOutput()

int juce::ChildProcess::readProcessOutput	(	void *	destBuffer,
		int	numBytesToRead )

Attempts to read some output from the child process.

This will attempt to read up to the given number of bytes of data from the process. It returns the number of bytes that were actually read.

readAllProcessOutput()

String juce::ChildProcess::readAllProcessOutput

(

)

Blocks until the process has finished, and then returns its complete output as a string.

waitForProcessToFinish()

bool juce::ChildProcess::waitForProcessToFinish

(

int

timeoutMs

)

const

Blocks until the process is no longer running.

getExitCode()

uint32 juce::ChildProcess::getExitCode

(

)

const

If the process has finished, this returns its exit code.

kill()

bool juce::ChildProcess::kill

(

)

Attempts to kill the child process.

Returns true if it succeeded. Trying to read from the process after calling this may result in undefined behaviour.

References ChildProcess().