The QProcess class is used to start external programs and to communicate with them. More...

Inheritance diagram for QtCore.QProcess:

Collaboration diagram for QtCore.QProcess:

Public Types
enum	ExitStatus { CrashExit = 1, NormalExit = 0 }
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enum	ProcessChannel { StandardError = 1, StandardOutput = 0 }
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enum	ProcessChannelMode { ForwardedChannels = 2, MergedChannels = 1, SeparateChannels = 0 }
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enum	ProcessError { Crashed = 1, FailedToStart = 0, ReadError = 3, Timedout = 2, UnknownError = 5, WriteError = 4 }
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enum	ProcessState { NotRunning = 0, Running = 2, Starting = 1 }
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Public Types inherited from QtCore.QIODevice
enum	OpenModeFlag { Append = 4, NotOpen = 0, ReadOnly = 1, ReadWrite = 3, Text = 16, Truncate = 8, Unbuffered = 32, WriteOnly = 2 }
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Public Member Functions
	QProcess (QObject parent=null)


override void	CreateProxy ()

override bool	AtEnd ()


override long	BytesAvailable ()


override long	BytesToWrite ()


override bool	CanReadLine ()


override void	Close ()


new void	CloseReadChannel (QProcess.ProcessChannel channel)


new void	CloseWriteChannel ()


new QProcess.ProcessError	OnError ()


new int	ExitCode ()


new QProcess.ExitStatus	exitStatus ()


override bool	IsSequential ()


new void	Kill ()


new QByteArray	ReadAllStandardError ()


new QByteArray	ReadAllStandardOutput ()


new void	SetStandardErrorFile (string fileName, QIODevice.OpenModeFlag mode=QIODevice.OpenModeFlag.Truncate)


new void	SetStandardInputFile (string fileName)


new void	SetStandardOutputFile (string fileName, QIODevice.OpenModeFlag mode=QIODevice.OpenModeFlag.Truncate)


new void	SetStandardOutputProcess (QProcess destination)


new void	Start (string program, QIODevice.OpenModeFlag mode=QIODevice.OpenModeFlag.ReadWrite)


new void	Start (string program, System.Collections.Generic.List< string > arguments, QIODevice.OpenModeFlag mode=QIODevice.OpenModeFlag.ReadWrite)


new QProcess.ProcessState	State ()


new void	Terminate ()


override bool	WaitForBytesWritten (int msecs=30000)


new bool	WaitForFinished (int msecs=30000)


override bool	WaitForReadyRead (int msecs=30000)


new bool	WaitForStarted (int msecs=30000)


new void	Dispose ()

Public Member Functions inherited from QtCore.QIODevice
	QIODevice ()


	QIODevice (QObject parent)


new string	ErrorString ()


new bool	GetChar (Pointer< sbyte > c)


new bool	IsOpen ()


new bool	IsReadable ()


new bool	IsTextModeEnabled ()


new bool	IsWritable ()


virtual bool	Open (QIODevice.OpenModeFlag mode)


new QIODevice.OpenModeFlag	OpenMode ()


new QByteArray	Peek (long maxlen)


new long	Peek (Pointer< sbyte > data, long maxlen)


virtual long	Pos ()


new bool	PutChar (sbyte c)


new QByteArray	Read (long maxlen)


new long	Read (Pointer< sbyte > data, long maxlen)


new QByteArray	ReadAll ()


new QByteArray	ReadLine (long maxlen=0)


new long	ReadLine (Pointer< sbyte > data, long maxlen)


virtual bool	Reset ()


virtual bool	Seek (long pos)


new void	SetTextModeEnabled (bool enabled)


virtual long	Size ()


new void	UngetChar (sbyte c)


new long	Write (QByteArray data)


new long	Write (string data)


new long	Write (string data, long len)


new void	Dispose ()

Public Member Functions inherited from QtCore.QObject
	QObject (QObject parent=null)


new bool	BlockSignals (bool b)


new System.Collections.Generic.List < QObject >	Children ()


new bool	Connect (QObject sender, string signal, string member, Qt.ConnectionType type=Qt.ConnectionType.AutoConnection)


new void	DeleteLater ()


new bool	Disconnect (QObject receiver, string member=null)


new bool	Disconnect (string signal=null, QObject receiver=null, string member=null)


new void	DumpObjectInfo ()


new void	DumpObjectTree ()


new System.Collections.Generic.List < QByteArray >	DynamicPropertyNames ()


virtual bool	OnEvent (QEvent arg1)


virtual bool	EventFilter (QObject arg1, QEvent arg2)


new bool	Inherits (string classname)


new void	InstallEventFilter (QObject arg1)


new bool	IsWidgetType ()


new void	KillTimer (int id)


new object	Property (string name)


new void	RemoveEventFilter (QObject arg1)


new bool	SetProperty (string name, object value)


new void	SetUserData (uint id, QObjectUserData data)

new bool	SignalsBlocked ()


new int	StartTimer (int interval)


new QObjectUserData	UserData (uint id)

new void	Dispose ()

Public Member Functions inherited from QtCore.Qt
delegate QTextStream	FuncQTextStreamQTextStream (QTextStream qTextStream)

delegate string	FuncStringQByteArray (QByteArray qByteArray)

delegate QByteArray	FuncQByteArrayString (string @string)

delegate void	ActionQtMsgTypeString (QtMsgType qtMsgType, string @string)

delegate QObject	FuncQObject ()

Static Public Member Functions
static int	Execute (string program)


static int	Execute (string program, System.Collections.Generic.List< string > arguments)


static bool	StartDetached (string program)


static bool	StartDetached (string program, System.Collections.Generic.List< string > arguments)


static bool	StartDetached (string program, System.Collections.Generic.List< string > arguments, string workingDirectory)


static bool	StartDetached (string program, System.Collections.Generic.List< string > arguments, string workingDirectory, ref long pid)


static System.Collections.Generic.List < string >	SystemEnvironment ()


static string	Tr (string s, string c=null)

static string	Tr (string s, string c, int n)

static string	TrUtf8 (string s, string c=null)

static string	TrUtf8 (string s, string c, int n)

Static Public Member Functions inherited from QtCore.QIODevice
static string	Tr (string s, string c=null)

static string	Tr (string s, string c, int n)

static string	TrUtf8 (string s, string c=null)

static string	TrUtf8 (string s, string c, int n)

Static Public Member Functions inherited from QtCore.QObject
static bool	Connect (QObject sender, QMetaMethod signal, QObject receiver, QMetaMethod method, Qt.ConnectionType type=Qt.ConnectionType.AutoConnection)


static bool	Connect (QObject sender, string signal, QObject receiver, string member, Qt.ConnectionType arg5=Qt.ConnectionType.AutoConnection)


static bool	Disconnect (QObject sender, QMetaMethod signal, QObject receiver, QMetaMethod member)


static bool	Disconnect (QObject sender, string signal, QObject receiver, string member)


static uint	RegisterUserData ()

static string	Tr (string s, string c=null)


static string	Tr (string s, string c, int n)


static string	TrUtf8 (string s, string c=null)


static string	TrUtf8 (string s, string c, int n)


Static Public Member Functions inherited from QtCore.Qt
static QDataStream	Write (QDataStream s, object p)

static QDataStream	Write (QDataStream arg1, QSizeF arg2)

static QTextStream	Write (QTextStream s, Qt.FuncQTextStreamQTextStream f)

static QDataStream	Write (QDataStream arg1, QPoint arg2)

static QDataStream	Write (QDataStream arg1, QLineF arg2)

static QDataStream	Write (QDataStream arg1, QPointF arg2)

static QDataStream	Write (QDataStream arg1, QChar arg2)

static QDataStream	Write (QDataStream arg1, QByteArray arg2)

static QDataStream	Write (QDataStream arg1, QEasingCurve arg2)

static QDataStream	Write (QDataStream arg1, QRectF arg2)

static QDataStream	Write (QDataStream arg1, QDateTime arg2)

static QDataStream	Write (QDataStream arg1, QUrl arg2)

static QDataStream	Write (QDataStream arg1, QTime arg2)

static QDataStream	Write (QDataStream arg1, QLocale arg2)

static QDataStream	Write (QDataStream arg1, QBitArray arg2)

static QDataStream	Write (QDataStream arg1, QUuid arg2)

static QDataStream	Write (QDataStream arg1, QLine arg2)

static QDataStream	Write (QDataStream arg1, QDate arg2)

static QDataStream	Write (QDataStream @out, QRegExp regExp)

static QDataStream	Write (QDataStream arg1, QRect arg2)

static QDataStream	Write (QDataStream arg1, QSize arg2)

static QDataStream	Write (QDataStream s, QVariant.Type p)

static QDataStream	Write (QDataStream arg1, string arg2)

static QDataStream	Write (QDataStream @out, System.Collections.Generic.List< string > list)

static QDataStream	Read (QDataStream arg1, QChar arg2)

static QDataStream	Read (QDataStream arg1, QLocale arg2)

static QDataStream	Read (QDataStream arg1, QRect arg2)

static QDataStream	Read (QDataStream arg1, QEasingCurve arg2)

static QDataStream	Read (QDataStream arg1, QDate arg2)

static QDataStream	Read (QDataStream arg1, QUrl arg2)

static QDataStream	Read (QDataStream arg1, QUuid arg2)

static QTextStream	Read (QTextStream s, Qt.FuncQTextStreamQTextStream f)

static QDataStream	Read (QDataStream arg1, QLineF arg2)

static QDataStream	Read (QDataStream arg1, QRectF arg2)

static QDataStream	Read (QDataStream arg1, QPointF arg2)

static QDataStream	Read (QDataStream arg1, QLine arg2)

static QDataStream	Read (QDataStream arg1, QBitArray arg2)

static QDataStream	Read (QDataStream arg1, QSize arg2)

static QDataStream	Read (QDataStream arg1, QDateTime arg2)

static QDataStream	Read (QDataStream arg1, QTime arg2)

static QDataStream	Read (QDataStream arg1, QPoint arg2)

static QDataStream	Read (QDataStream @in, QRegExp regExp)

static QDataStream	Read (QDataStream s, object p)

static QDataStream	Read (QDataStream arg1, QByteArray arg2)

static QDataStream	Read (QDataStream arg1, QSizeF arg2)

static QDataStream	Read (QDataStream arg1, string arg2)

static QDataStream	Read (QDataStream s, QVariant.Type p)

static QDataStream	Read (QDataStream @in, System.Collections.Generic.List< string > list)

static double	qAcos (double v)

static void	qAddPostRoutine (System.Action arg1)

static string	qAppName ()

static double	qAsin (double v)

static double	qAtan (double v)

static double	qAtan2 (double x, double y)

static void	qBadAlloc ()

static int	qCeil (double v)

static ushort	qChecksum (string s, uint len)

static QByteArray	qCompress (QByteArray data)

static QByteArray	qCompress (QByteArray data, int compressionLevel=-1)

static QByteArray	qCompress (Pointer< byte > data, int nbytes)

static QByteArray	qCompress (Pointer< byte > data, int nbytes, int compressionLevel=-1)

static double	qCos (double v)

static double	qExp (double v)

static double	qFabs (double v)

static double	qFastCos (double x)

static double	qFastSin (double x)

static string	qFlagLocation (string method)

static int	qFloor (double v)

static bool	qFuzzyCompare (double p1, double p2)

static bool	qFuzzyCompare (float p1, float p2)

static bool	qFuzzyIsNull (double d)

static bool	qFuzzyIsNull (float f)

static uint	qHash (QBitArray key)

static uint	qHash (QChar key)

static uint	qHash (QStringRef key)

static uint	qHash (QUrl url)

static uint	qHash (QPersistentModelIndex index)

static uint	qHash (QByteArray key)

static uint	qHash (QModelIndex index)

static uint	qHash (uint key)

static uint	qHash (sbyte key)

static uint	qHash (byte key)

static uint	qHash (short key)

static uint	qHash (NativeLong key)

static uint	qHash (ushort key)

static uint	qHash (long key)

static uint	qHash (ulong key)

static uint	qHash (int key)

static uint	qHash (string key)

static uint	qHash (NativeULong key)

static double	qInf ()

static Qt.ActionQtMsgTypeString	qInstallMsgHandler (Qt.ActionQtMsgTypeString arg1)

static int	qIntCast (float f)

static int	qIntCast (double f)

static bool	qIsFinite (double d)

static bool	qIsFinite (float f)

static bool	qIsInf (float f)

static bool	qIsInf (double d)

static bool	qIsNaN (float f)

static bool	qIsNaN (double d)

static bool	qIsNull (float f)

static bool	qIsNull (double d)

static double	qLn (double v)

static double	qPow (double x, double y)

static double	qQNaN ()

static void	qRegisterStaticPluginInstanceFunction (Qt.FuncQObject function)

static void	qRemovePostRoutine (System.Action arg1)

static int	qRound (double d)

static long	qRound64 (double d)

static double	qSNaN ()

static bool	qSharedBuild ()

static double	qSin (double v)

static double	qSqrt (double v)

static bool	qStringComparisonHelper (QStringRef s1, string s2)

static double	qTan (double v)

static QByteArray	qUncompress (QByteArray data)

static QByteArray	qUncompress (Pointer< byte > data, int nbytes)

static string	qVersion ()

static void	Qbswap_helper (Pointer< byte > src, Pointer< byte > dest, int size)

static QByteArray	Qgetenv (string varName)

static bool	Qputenv (string varName, QByteArray value)

static int	Qrand ()

static void	Qsrand (uint seed)

static int	Qstrcmp (QByteArray str1, QByteArray str2)

static int	Qstrcmp (QByteArray str1, string str2)

static int	Qstrcmp (string str1, QByteArray str2)

static int	Qstrcmp (string str1, string str2)

static Pointer< sbyte >	Qstrcpy (Pointer< sbyte > dst, string src)

static Pointer< sbyte >	Qstrdup (string arg1)

static int	Qstricmp (string arg1, string arg2)

static uint	Qstrlen (string str)

static int	Qstrncmp (string str1, string str2, uint len)

static Pointer< sbyte >	Qstrncpy (Pointer< sbyte > dst, string src, uint len)

static int	Qstrnicmp (string arg1, string arg2, uint len)

static uint	Qstrnlen (string str, uint maxlen)

static string	QtTrId (string id, int n=-1)

Protected Member Functions
	QProcess (System.Type dummy)

new void	OnError (QProcess.ProcessError error)


new void	OnFinished (int exitCode)


new void	OnFinished (int exitCode, QProcess.ExitStatus exitStatus)


override long	ReadData (Pointer< sbyte > data, long maxlen)


new void	OnReadyReadStandardError ()


new void	OnReadyReadStandardOutput ()


new void	SetProcessState (QProcess.ProcessState state)


virtual void	SetupChildProcess ()


new void	OnStarted ()


new void	OnStateChanged (QProcess.ProcessState state)


override long	WriteData (string data, long len)


Protected Member Functions inherited from QtCore.QIODevice
	QIODevice (System.Type dummy)

new void	OnAboutToClose ()


new void	OnBytesWritten (long bytes)


new void	OnReadChannelFinished ()


virtual long	ReadLineData (Pointer< sbyte > data, long maxlen)


new void	OnReadyRead ()


new void	SetErrorString (string errorString)


new void	SetOpenMode (QIODevice.OpenModeFlag openMode)


Protected Member Functions inherited from QtCore.QObject
	QObject (System.Type dummy)

virtual void	OnChildEvent (QChildEvent arg1)


virtual void	ConnectNotify (string signal)


virtual void	OnCustomEvent (QEvent arg1)


new void	OnDestroyed (QObject arg1=null)


virtual void	DisconnectNotify (string signal)


new int	Receivers (string signal)


new QObject	Sender ()


new int	SenderSignalIndex ()


virtual void	OnTimerEvent (QTimerEvent arg1)

Properties
Slot	Started


Slot< System.Int32 >	Finished


Slot< System.Int32, QProcess.ExitStatus >	FinishedExitStatus

Slot< QProcess.ProcessError >	Error


Slot< QProcess.ProcessState >	StateChanged


Slot	ReadyReadStandardOutput


Slot	ReadyReadStandardError


new System.Collections.Generic.List < string >	Environment `[get, set]`


new string	NativeArguments `[get, set]`


new QProcess.ProcessChannelMode	processChannelMode `[get, set]`


new QProcessEnvironment	ProcessEnvironment `[get, set]`


new QProcess.ProcessChannel	ReadChannel `[get, set]`


new QProcess.ProcessChannelMode	ReadChannelMode `[get, set]`


new string	WorkingDirectory `[get, set]`


static new QMetaObject	StaticMetaObject `[get]`

new IQProcessSignals	Emit `[get]`

Properties inherited from QtCore.QIODevice
Slot	ReadyRead


Slot< System.Int64 >	BytesWritten


Slot	AboutToClose


Slot	ReadChannelFinished


static new QMetaObject	StaticMetaObject `[get]`

new IQIODeviceSignals	Emit `[get]`

Properties inherited from QtCore.QObject
virtual EventHandler < QEventArgs< QChildEvent > >	ChildEvent


virtual EventHandler < QEventArgs< QEvent > >	CustomEvent


virtual EventHandler < QEventArgs< QEvent > >	Event


virtual EventHandler < QEventArgs< QTimerEvent > >	TimerEvent


Slot< QObject >	DestroyedQObject

Slot	Destroyed


new QObject	Parent `[get, set]`


virtual System.IntPtr	SmokeObject `[get, set]`

new string	ObjectName `[get, set]`


static new QMetaObject	StaticMetaObject `[get]`


static new QMetaObject	StaticQtMetaObject `[get]`

new IQObjectSignals	Emit `[get]`

Additional Inherited Members
Protected Attributes inherited from QtCore.QObject
object	Q_EMIT = null

SmokeInvocation	interceptor

readonly List< QEventHandler >	eventFilters = new List<QEventHandler>()

Detailed Description

The QProcess class is used to start external programs and to communicate with them.

Running a Process

To start a process, pass the name and command line arguments of the program you want to run as arguments to start(). Arguments are supplied as individual strings in a QStringList.

For example, the following code snippet runs the analog clock example in the Motif style on X11 platforms by passing strings containing "-style" and "motif" as two items in the list of arguments:

QObject *parent;

...

QString program = "./path/to/Qt/examples/widgets/analogclock";

QStringList arguments;

arguments << "-style" << "motif";

QProcess *myProcess = new QProcess(parent);

myProcess->start(program, arguments);

QProcess then enters the Starting state, and when the program has started, QProcess enters the Running state and emits started().

QProcess allows you to treat a process as a sequential I/O device. You can write to and read from the process just as you would access a network connection using QTcpSocket. You can then write to the process's standard input by calling write(), and read the standard output by calling read(), readLine(), and getChar(). Because it inherits QIODevice, QProcess can also be used as an input source for QXmlReader, or for generating data to be uploaded using QFtp.

Note: On Windows CE and Symbian, reading and writing to a process is not supported.

When the process exits, QProcess reenters the NotRunning state (the initial state), and emits finished().

The finished() signal provides the exit code and exit status of the process as arguments, and you can also call exitCode() to obtain the exit code of the last process that finished, and exitStatus() to obtain its exit status. If an error occurs at any point in time, QProcess will emit the error() signal. You can also call error() to find the type of error that occurred last, and state() to find the current process state.

Communicating via Channels

Processes have two predefined output channels: The standard output channel (stdout) supplies regular console output, and the standard error channel (stderr) usually supplies the errors that are printed by the process. These channels represent two separate streams of data. You can toggle between them by calling setReadChannel(). QProcess emits readyRead() when data is available on the current read channel. It also emits readyReadStandardOutput() when new standard output data is available, and when new standard error data is available, readyReadStandardError() is emitted. Instead of calling read(), readLine(), or getChar(), you can explicitly read all data from either of the two channels by calling readAllStandardOutput() or readAllStandardError().

The terminology for the channels can be misleading. Be aware that the process's output channels correspond to QProcess's read channels, whereas the process's input channels correspond to QProcess's write channels. This is because what we read using QProcess is the process's output, and what we write becomes the process's input.

QProcess can merge the two output channels, so that standard output and standard error data from the running process both use the standard output channel. Call setProcessChannelMode() with MergedChannels before starting the process to activative this feature. You also have the option of forwarding the output of the running process to the calling, main process, by passing ForwardedChannels as the argument.

Certain processes need special environment settings in order to operate. You can set environment variables for your process by calling setEnvironment(). To set a working directory, call setWorkingDirectory(). By default, processes are run in the current working directory of the calling process.

Note: On Symbian, setting environment or working directory is not supported. The working directory will always be the private directory of the running process.

Note: On QNX, setting the working directory may cause all application threads, with the exception of the QProcess caller thread, to temporarily freeze, owing to a limitation in the operating system.

Synchronous Process API

QProcess provides a set of functions which allow it to be used without an event loop, by suspending the calling thread until certain signals are emitted:

waitForStarted() blocks until the process has started.

waitForReadyRead() blocks until new data is available for reading on the current read channel.

waitForBytesWritten() blocks until one payload of data has been written to the process.

waitForFinished() blocks until the process has finished.

Calling these functions from the main thread (the thread that calls QApplication::exec()) may cause your user interface to freeze.

The following example runs gzip to compress the string "Qt rocks!", without an event loop:

QProcess gzip;

gzip.start("gzip", QStringList() << "-c");

if (!gzip.waitForStarted())

return false;

gzip.write("Qt rocks!");

gzip.closeWriteChannel();

if (!gzip.waitForFinished())

return false;

QByteArray result = gzip.readAll();

Notes for Windows Users

Some Windows commands (for example, dir) are not provided by separate applications, but by the command interpreter itself. If you attempt to use QProcess to execute these commands directly, it won't work. One possible solution is to execute the command interpreter itself (cmd.exe on some Windows systems), and ask the interpreter to execute the desired command.

Symbian Platform Security Requirements

On Symbian, processes which use the functions kill() or terminate() must have the PowerMgmt platform security capability. If the client process lacks this capability, these functions will fail.

Platform security capabilities are added via the TARGET.CAPABILITY qmake variable.

See also QBuffer, QFile, and QTcpSocket.

Member Enumeration Documentation

enum QtCore.QProcess.ExitStatus

This enum describes the different exit statuses of QProcess.

See also exitStatus().

Enumerator:

CrashExit	The process crashed.
NormalExit	The process exited normally.

enum QtCore.QProcess.ProcessChannel

This enum describes the process channels used by the running process. Pass one of these values to setReadChannel() to set the current read channel of QProcess.

See also state().

Enumerator:

NotRunning	The process is not running.
Running	The process is running and is ready for reading and writing.
Starting	The process is starting, but the program has not yet been invoked.

Constructor & Destructor Documentation

QtCore.QProcess.QProcess ( System.Type dummy )

protected

QtCore.QProcess.QProcess ( QObject parent = null )

Constructs a QProcess object with the given parent.

Member Function Documentation

override bool QtCore.QProcess.AtEnd ( )

virtual

Reimplemented from QIODevice::atEnd().

Returns true if the process is not running, and no more data is available for reading; otherwise returns false.

Reimplemented from QtCore.QIODevice.

override long QtCore.QProcess.BytesAvailable ( )

virtual

Reimplemented from QIODevice::bytesAvailable().

Reimplemented from QtCore.QIODevice.

override long QtCore.QProcess.BytesToWrite ( )

virtual

Reimplemented from QIODevice::bytesToWrite().

Reimplemented from QtCore.QIODevice.

override bool QtCore.QProcess.CanReadLine ( )

virtual

Reimplemented from QIODevice::canReadLine().

This function operates on the current read channel.

See also readChannel() and setReadChannel().

Reimplemented from QtCore.QIODevice.

override void QtCore.QProcess.Close ( )

virtual

Reimplemented from QIODevice::close().

Closes all communication with the process and kills it. After calling this function, QProcess will no longer emit readyRead(), and data can no longer be read or written.

Reimplemented from QtCore.QIODevice.

new void QtCore.QProcess.CloseReadChannel ( QProcess.ProcessChannel channel )

Closes the read channel channel. After calling this function, QProcess will no longer receive data on the channel. Any data that has already been received is still available for reading.

Call this function to save memory, if you are not interested in the output of the process.

See also closeWriteChannel() and setReadChannel().

new void QtCore.QProcess.CloseWriteChannel ( )

Schedules the write channel of QProcess to be closed. The channel will close once all data has been written to the process. After calling this function, any attempts to write to the process will fail.

Closing the write channel is necessary for programs that read input data until the channel has been closed. For example, the program "more" is used to display text data in a console on both Unix and Windows. But it will not display the text data until QProcess's write channel has been closed. Example:

QProcess more;

more.start("more");

more.write("Text to display");

more.closeWriteChannel();

// QProcess will emit readyRead() once "more" starts printing

The write channel is implicitly opened when start() is called.

See also state().

new void QtCore.QProcess.OnError ( QProcess.ProcessError error )

protected

Returns the type of error that occurred last.

See also state().

new void QtCore.QProcess.OnFinished ( int exitCode )

protected

This signal is emitted when the process finishes. exitCode is the exit code of the process, and exitStatus is the exit status. After the process has finished, the buffers in QProcess are still intact. You can still read any data that the process may have written before it finished.

See also exitStatus().

new void QtCore.QProcess.OnFinished	(	int	exitCode,
		QProcess.ExitStatus	exitStatus
	)

protected

This signal is emitted when the process finishes. exitCode is the exit code of the process, and exitStatus is the exit status. After the process has finished, the buffers in QProcess are still intact. You can still read any data that the process may have written before it finished.

See also exitStatus().

new void QtCore.QProcess.OnReadyReadStandardError ( )

protected

This signal is emitted when the process has made new data available through its standard error channel (stderr). It is emitted regardless of the current read channel.

See also readAllStandardError() and readChannel().

new void QtCore.QProcess.OnReadyReadStandardOutput ( )

protected

This signal is emitted when the process has made new data available through its standard output channel (stdout). It is emitted regardless of the current read channel.

See also readAllStandardOutput() and readChannel().

new void QtCore.QProcess.OnStarted ( )

protected

This signal is emitted by QProcess when the process has started, and state() returns Running.

new void QtCore.QProcess.OnStateChanged ( QProcess.ProcessState state )

protected

This signal is emitted whenever the state of QProcess changes. The newState argument is the state QProcess changed to.

new QByteArray QtCore.QProcess.ReadAllStandardError ( )

Regardless of the current read channel, this function returns all data available from the standard error of the process as a QByteArray.

See also readyReadStandardError(), readAllStandardOutput(), readChannel(), and setReadChannel().

new QByteArray QtCore.QProcess.ReadAllStandardOutput ( )

Regardless of the current read channel, this function returns all data available from the standard output of the process as a QByteArray.

See also readyReadStandardOutput(), readAllStandardError(), readChannel(), and setReadChannel().

override long QtCore.QProcess.ReadData	(	Pointer< sbyte >	data,
		long	maxlen
	)

protectedvirtual

Reimplemented from QIODevice::readData().

Implements QtCore.QIODevice.

new void QtCore.QProcess.SetProcessState ( QProcess.ProcessState state )

protected

Sets the current state of the QProcess to the state specified.

See also state().

new void QtCore.QProcess.SetStandardErrorFile	(	string	fileName,
		QIODevice.OpenModeFlag	mode = `QIODevice.OpenModeFlag.Truncate`
	)

Redirects the process' standard error to the file fileName. When the redirection is in place, the standard error read channel is closed: reading from it using read() will always fail, as will readAllStandardError(). The file will be appended to if mode is Append, otherwise, it will be truncated.

See setStandardOutputFile() for more information on how the file is opened.

Note: if setProcessChannelMode() was called with an argument of QProcess::MergedChannels, this function has no effect.

This function was introduced in Qt 4.2.

See also setStandardInputFile(), setStandardOutputFile(), and setStandardOutputProcess().

new void QtCore.QProcess.SetStandardInputFile ( string fileName )

Redirects the process' standard input to the file indicated by fileName. When an input redirection is in place, the QProcess object will be in read-only mode (calling write() will result in error).

If the file fileName does not exist at the moment start() is called or is not readable, starting the process will fail.

Calling setStandardInputFile() after the process has started has no effect.

This function was introduced in Qt 4.2.

See also setStandardOutputFile(), setStandardErrorFile(), and setStandardOutputProcess().

new void QtCore.QProcess.SetStandardOutputFile	(	string	fileName,
		QIODevice.OpenModeFlag	mode = `QIODevice.OpenModeFlag.Truncate`
	)

Redirects the process' standard output to the file fileName. When the redirection is in place, the standard output read channel is closed: reading from it using read() will always fail, as will readAllStandardOutput().

If the file fileName doesn't exist at the moment start() is called, it will be created. If it cannot be created, the starting will fail.

If the file exists and mode is QIODevice::Truncate, the file will be truncated. Otherwise (if mode is QIODevice::Append), the file will be appended to.

Calling setStandardOutputFile() after the process has started has no effect.

This function was introduced in Qt 4.2.

See also setStandardInputFile(), setStandardErrorFile(), and setStandardOutputProcess().

new void QtCore.QProcess.SetStandardOutputProcess ( QProcess destination )

Pipes the standard output stream of this process to the destination process' standard input.

The following shell command:

command1 | command2

Can be accomplished with QProcesses with the following code:

QProcess process1;

QProcess process2;

process1.setStandardOutputProcess(&process2);

process1.start("command1");

process2.start("command2");

This function was introduced in Qt 4.2.

virtual void QtCore.QProcess.SetupChildProcess ( )

protectedvirtual

This function is called in the child process context just before the program is executed on Unix or Mac OS X (i.e., after fork(), but before execve()). Reimplement this function to do last minute initialization of the child process. Example:

class SandboxProcess : public QProcess

{

...

protected:

void setupChildProcess();

...

};

void SandboxProcess::setupChildProcess()

{

// Drop all privileges in the child process, and enter

// a chroot jail.

#if defined Q_OS_UNIX

::setgroups(0, 0);

::chroot("/etc/safe");

::chdir("/");

::setgid(safeGid);

::setuid(safeUid);

::umask(0);

#endif

}

You cannot exit the process (by calling exit(), for instance) from this function. If you need to stop the program before it starts execution, your workaround is to emit finished() and then call exit().

Warning: This function is called by QProcess on Unix and Mac OS X only. On Windows and QNX, it is not called.

new void QtCore.QProcess.Start	(	string	program,
		QIODevice.OpenModeFlag	mode = `QIODevice.OpenModeFlag.ReadWrite`
	)

Starts the given program in a new process, if none is already running, passing the command line arguments in arguments. The OpenMode is set to mode.

The QProcess object will immediately enter the Starting state. If the process starts successfully, QProcess will emit started(); otherwise, error() will be emitted. If the QProcess object is already running a process, a warning may be printed at the console, and the existing process will continue running.

Note: Processes are started asynchronously, which means the started() and error() signals may be delayed. Call waitForStarted() to make sure the process has started (or has failed to start) and those signals have been emitted.

Note: No further splitting of the arguments is performed.

Windows: Arguments that contain spaces are wrapped in quotes.

See also pid(), started(), and waitForStarted().

new void QtCore.QProcess.Start	(	string	program,
		System.Collections.Generic.List< string >	arguments,
		QIODevice.OpenModeFlag	mode = `QIODevice.OpenModeFlag.ReadWrite`
	)

Starts the given program in a new process, if none is already running, passing the command line arguments in arguments. The OpenMode is set to mode.

The QProcess object will immediately enter the Starting state. If the process starts successfully, QProcess will emit started(); otherwise, error() will be emitted. If the QProcess object is already running a process, a warning may be printed at the console, and the existing process will continue running.

Note: Processes are started asynchronously, which means the started() and error() signals may be delayed. Call waitForStarted() to make sure the process has started (or has failed to start) and those signals have been emitted.

Note: No further splitting of the arguments is performed.

Windows: Arguments that contain spaces are wrapped in quotes.

See also pid(), started(), and waitForStarted().

static bool QtCore.QProcess.StartDetached ( string program )

static

This is an overloaded function.

Starts the program program in a new process. program is a single string of text containing both the program name and its arguments. The arguments are separated by one or more spaces.

The program string can also contain quotes, to ensure that arguments containing spaces are correctly supplied to the new process.

static bool QtCore.QProcess.StartDetached	(	string	program,
		System.Collections.Generic.List< string >	arguments
	)

static

Starts the program program with the given arguments in a new process, and detaches from it. Returns true on success; otherwise returns false. If the calling process exits, the detached process will continue to live.

Note: Arguments that contain spaces are not passed to the process as separate arguments.

Unix: The started process will run in its own session and act like a daemon.

Windows: Arguments that contain spaces are wrapped in quotes. The started process will run as a regular standalone process.

static bool QtCore.QProcess.StartDetached	(	string	program,
		System.Collections.Generic.List< string >	arguments,
		string	workingDirectory
	)

static

Starts the program program with the arguments arguments in a new process, and detaches from it. Returns true on success; otherwise returns false. If the calling process exits, the detached process will continue to live.

Note that arguments that contain spaces are not passed to the process as separate arguments.

Unix: The started process will run in its own session and act like a daemon.

Windows: Arguments that contain spaces are wrapped in quotes. The started process will run as a regular standalone process.

The process will be started in the directory workingDirectory.

Note: On QNX, this may cause all application threads to temporarily freeze.

If the function is successful then *pid is set to the process identifier of the started process.

static bool QtCore.QProcess.StartDetached	(	string	program,
		System.Collections.Generic.List< string >	arguments,
		string	workingDirectory,
		ref long	pid
	)

static

Starts the program program with the arguments arguments in a new process, and detaches from it. Returns true on success; otherwise returns false. If the calling process exits, the detached process will continue to live.

Note that arguments that contain spaces are not passed to the process as separate arguments.

Unix: The started process will run in its own session and act like a daemon.

Windows: Arguments that contain spaces are wrapped in quotes. The started process will run as a regular standalone process.

The process will be started in the directory workingDirectory.

Note: On QNX, this may cause all application threads to temporarily freeze.

If the function is successful then *pid is set to the process identifier of the started process.

new QProcess.ProcessState QtCore.QProcess.State ( )

Returns the current state of the process.

Property Documentation

new IQProcessSignals QtCore.QProcess.Emit

getprotected

new System.Collections.Generic.List<string> QtCore.QProcess.Environment

getset

This function is deprecated.

Returns the environment that QProcess will use when starting a process, or an empty QStringList if no environment has been set using setEnvironment() or setEnvironmentHash(). If no environment has been set, the environment of the calling process will be used.

Note: The environment settings are ignored on Windows CE and Symbian, as there is no concept of an environment.

This function is deprecated.

Sets the environment that QProcess will use when starting a process to the environment specified which consists of a list of key=value pairs.

For example, the following code adds the C:\\BIN directory to the list of executable paths (PATHS) on Windows:

QProcess process;

QStringList env = QProcess::systemEnvironment();

env << "TMPDIR=C:\\MyApp\\temp"; // Add an environment variable

env.replaceInStrings(QRegExp("^PATH=(.*)", Qt::CaseInsensitive), "PATH=\\1;C:\\Bin");

process.setEnvironment(env);

process.start("myapp");

Note: This function is less efficient than the setProcessEnvironment() function.

Slot<QProcess.ProcessError> QtCore.QProcess.Error

addremove

Returns the type of error that occurred last.

See also state().

Slot<System.Int32> QtCore.QProcess.Finished

addremove

This signal is emitted when the process finishes. exitCode is the exit code of the process, and exitStatus is the exit status. After the process has finished, the buffers in QProcess are still intact. You can still read any data that the process may have written before it finished.

See also exitStatus().

Slot<System.Int32,QProcess.ExitStatus> QtCore.QProcess.FinishedExitStatus

addremove

new string QtCore.QProcess.NativeArguments

getset

Returns the additional native command line arguments for the program.

Note: This function is available only on the Windows and Symbian platforms.

This function was introduced in Qt 4.7.

This is an overloaded function.

Sets additional native command line arguments for the program.

On operating systems where the system API for passing command line arguments to a subprocess natively uses a single string, one can conceive command lines which cannot be passed via QProcess's portable list-based API. In such cases this function must be used to set a string which is appended to the string composed from the usual argument list, with a delimiting space.

Note: This function is available only on the Windows and Symbian platforms.

This function was introduced in Qt 4.7.

new QProcess.ProcessChannelMode QtCore.QProcess.processChannelMode

getset

Returns the channel mode of the QProcess standard output and standard error channels.

This function was introduced in Qt 4.2.

Sets the channel mode of the QProcess standard output and standard error channels to the mode specified. This mode will be used the next time start() is called. For example:

QProcess builder;

builder.setProcessChannelMode(QProcess::MergedChannels);

builder.start("make", QStringList() << "-j2");

if (!builder.waitForFinished())

qDebug() << "Make failed:" << builder.errorString();

else

qDebug() << "Make output:" << builder.readAll();

This function was introduced in Qt 4.2.

new QProcessEnvironment QtCore.QProcess.ProcessEnvironment

getset

Returns the environment that QProcess will use when starting a process, or an empty object if no environment has been set using setEnvironment() or setProcessEnvironment(). If no environment has been set, the environment of the calling process will be used.

Note: The environment settings are ignored on Windows CE, as there is no concept of an environment.

This function was introduced in Qt 4.6.

Sets the environment that QProcess will use when starting a process to the environment object.

For example, the following code adds the C:\\BIN directory to the list of executable paths (PATHS) on Windows and sets TMPDIR:

QProcess process;

QProcessEnvironment env = QProcessEnvironment::systemEnvironment();

env.insert("TMPDIR", "C:\\MyApp\\temp"); // Add an environment variable

env.insert("PATH", env.value("Path") + ";C:\\Bin");

process.setProcessEnvironment(env);

process.start("myapp");

Note how, on Windows, environment variable names are case-insensitive.

This function was introduced in Qt 4.6.

new QProcess.ProcessChannel QtCore.QProcess.ReadChannel

getset

Returns the current read channel of the QProcess.

Sets the current read channel of the QProcess to the given channel. The current input channel is used by the functions read(), readAll(), readLine(), and getChar(). It also determines which channel triggers QProcess to emit readyRead().

new QProcess.ProcessChannelMode QtCore.QProcess.ReadChannelMode

getset

Returns the read channel mode of the QProcess. This function is equivalent to processChannelMode()

Use setProcessChannelMode(mode) instead.

Slot QtCore.QProcess.ReadyReadStandardError

addremove

This signal is emitted when the process has made new data available through its standard error channel (stderr). It is emitted regardless of the current read channel.

See also readAllStandardError() and readChannel().

Slot QtCore.QProcess.ReadyReadStandardOutput

addremove

This signal is emitted when the process has made new data available through its standard output channel (stdout). It is emitted regardless of the current read channel.

See also readAllStandardOutput() and readChannel().

Slot QtCore.QProcess.Started

addremove

This signal is emitted by QProcess when the process has started, and state() returns Running.

Slot<QProcess.ProcessState> QtCore.QProcess.StateChanged

addremove

This signal is emitted whenever the state of QProcess changes. The newState argument is the state QProcess changed to.

new QMetaObject QtCore.QProcess.StaticMetaObject

staticget

new string QtCore.QProcess.WorkingDirectory

getset

If QProcess has been assigned a working directory, this function returns the working directory that the QProcess will enter before the program has started. Otherwise, (i.e., no directory has been assigned,) an empty string is returned, and QProcess will use the application's current working directory instead.

Sets the working directory to dir. QProcess will start the process in this directory. The default behavior is to start the process in the working directory of the calling process.

Note: The working directory setting is ignored on Symbian; the private directory of the process is considered its working directory.

Note: On QNX, this may cause all application threads to temporarily freeze.

StandardError	The standard error (stderr) of the running process.
StandardOutput	The standard output (stdout) of the running process.

ForwardedChannels	QProcess forwards the output of the running process onto the main process. Anything the child process writes to its standard output and standard error will be written to the standard output and standard error of the main process.
MergedChannels	QProcess merges the output of the running process into the standard output channel (stdout). The standard error channel (stderr) will not receive any data. The standard output and standard error data of the running process are interleaved.
SeparateChannels	QProcess manages the output of the running process, keeping standard output and standard error data in separate internal buffers. You can select the QProcess's current read channel by calling setReadChannel(). This is the default channel mode of QProcess.

Crashed	The process crashed some time after starting successfully.
FailedToStart	The process failed to start. Either the invoked program is missing, or you may have insufficient permissions to invoke the program.
ReadError	An error occurred when attempting to read from the process. For example, the process may not be running.
Timedout	The last waitFor...() function timed out. The state of QProcess is unchanged, and you can try calling waitFor...() again.
UnknownError	An unknown error occurred. This is the default return value of error().
WriteError	An error occurred when attempting to write to the process. For example, the process may not be running, or it may have closed its input channel.

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Property Documentation