juce::ChildProcess Class Reference

Launches and monitors a child process. More...

#include <juce_ChildProcess.h>

Collaboration diagram for juce::ChildProcess:

Classes
class	ActiveProcess

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

Private Attributes
std::unique_ptr< ActiveProcess >	activeProcess

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.

@tags{Core}

Member Enumeration Documentation

StreamFlags

enum juce::ChildProcess::StreamFlags

These flags are used by the start() methods.

Enumerator
wantStdOut
wantStdErr

Constructor & Destructor Documentation

ChildProcess()

juce::ChildProcess::ChildProcess

(

)

Creates a process object.

To actually launch the process, use start().

~ChildProcess()

juce::ChildProcess::~ChildProcess

(

)

Destructor.

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

Member Function Documentation

getExitCode()

uint32 juce::ChildProcess::getExitCode

(

)

const

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

isRunning()

bool juce::ChildProcess::isRunning

(

)

const

Returns true if the child process is alive.

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.

readAllProcessOutput()

String juce::ChildProcess::readAllProcessOutput

(

)

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

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.

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, and juce::StringArray::fromTokens().

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 activeProcess, and juce::StringArray::size().

waitForProcessToFinish()

bool juce::ChildProcess::waitForProcessToFinish

(

int

timeoutMs

)

const

Blocks until the process is no longer running.

Member Data Documentation

activeProcess

std::unique_ptr<ActiveProcess> juce::ChildProcess::activeProcess

private

Referenced by start().

---

The documentation for this class was generated from the following files:

• juce_ChildProcess.h
• juce_posix_SharedCode.h