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<h3 class=fn>bool <a name="launch"></a>QProcess::launch ( const&nbsp;QByteArray&nbsp;&amp;&nbsp;buf, QStringList&nbsp;*&nbsp;env = 0 )<tt> [virtual]</tt>
</h3>
Runs the process and writes the data <em>buf</em> to the process's standard input.
If all the data is written to standard input, standard input is
closed. The command is searched for in the path for executable programs;
you can also use an absolute path in the command itself.
<p> If <em>env</em> is null, then the process is started with the same environment as
the starting process. If <em>env</em> is non-null, then the values in the
stringlist are interpreted as environment setttings of the form <tt>key=value</tt> and the process is started with these environment settings. For
convenience, there is a small exception to this rule under Unix: if <em>env</em>
does not contain any settings for the environment variable <tt>LD_LIBRARY_PATH</tt>, then this variable is inherited from the starting process.
<p> Returns TRUE if the process could be started; otherwise returns FALSE.
<p> Note that you should not use the slots <a href="#writeToStdin">writeToStdin</a>() and <a href="#closeStdin">closeStdin</a>() on
processes started with <a href="#launch">launch</a>(), since the result is not well-defined. If you
need these slots, use <a href="#start">start</a>() instead.
<p> The process may or may not read the <em>buf</em> data sent to its standard
input.
<p> You can call this function even when a process that was started with
this instance is still running. Be aware that if you do this the
standard input of the process that was launched first will be
closed, with any pending data being deleted, and the process will be
left to run out of your control. Similarly, if the process could not
be started the standard input will be closed and the pending data
deleted. (On operating systems that have zombie processes, Qt will
also wait() on the old process.)
<p> The object emits the signal <a href="#launchFinished">launchFinished</a>() when this function
call is finished. If the start was successful, this signal is
emitted after all the data has been written to standard input. If
the start failed, then this signal is emitted immediately.
<p> <p>See also <a href="#start">start</a>() and <a href="#launchFinished">launchFinished</a>().

<h3 class=fn>bool <a name="launch-2"></a>QProcess::launch ( const&nbsp;QString&nbsp;&amp;&nbsp;buf, QStringList&nbsp;*&nbsp;env = 0 )<tt> [virtual]</tt>
</h3> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> The data <em>buf</em> is written to standard input with <a href="#writeToStdin">writeToStdin</a>()
using the QString::local8Bit() representation of the strings.

<h3 class=fn>void <a name="launchFinished"></a>QProcess::launchFinished ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the process was started with <a href="#launch">launch</a>().
If the start was successful, this signal is emitted after all the
data has been written to standard input. If the start failed, then
this signal is emitted immediately.
<p> <p>See also <a href="#launch">launch</a>() and QObject::deleteLater().

<h3 class=fn>bool <a name="normalExit"></a>QProcess::normalExit () const
</h3>
Returns TRUE if the process has exited normally; otherwise returns
FALSE. This implies that this function returns FALSE if the process
is still running.
<p> <p>See also <a href="#isRunning">isRunning</a>(), <a href="#exitStatus">exitStatus</a>() and <a href="#processExited">processExited</a>().

<h3 class=fn>void <a name="processExited"></a>QProcess::processExited ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the process has exited.
<p> <p>See also <a href="#isRunning">isRunning</a>(), <a href="#normalExit">normalExit</a>(), <a href="#exitStatus">exitStatus</a>(), <a href="#start">start</a>() and <a href="#launch">launch</a>().

<h3 class=fn>PID <a name="processIdentifier"></a>QProcess::processIdentifier ()
</h3>
Returns platform dependent information about the process. This can be used
together with platform specific system calls.
<p> Under Unix the return value is the PID of the process, or -1 if no process is
belonging to this object.
<p> Under Windows it is a pointer to the <tt>PROCESS_INFORMATION</tt> struct, or 0 if
no process is belonging to this object.

<h3 class=fn>QString <a name="readLineStderr"></a>QProcess::readLineStderr ()<tt> [virtual]</tt>
</h3>
Reads a line of text from standard error, excluding any trailing newline or
carriage return characters and returns it. Returns QString::null if
<a href="#canReadLineStderr">canReadLineStderr</a>() returns FALSE.
<p> <p>See also <a href="#canReadLineStderr">canReadLineStderr</a>(), <a href="#readyReadStderr">readyReadStderr</a>(), <a href="#readStderr">readStderr</a>() and <a href="#readLineStdout">readLineStdout</a>().

<h3 class=fn>QString <a name="readLineStdout"></a>QProcess::readLineStdout ()<tt> [virtual]</tt>
</h3>
Reads a line of text from standard output, excluding any trailing newline or
carriage return characters, and returns it. Returns QString::null if
<a href="#canReadLineStdout">canReadLineStdout</a>() returns FALSE.
<p> <p>See also <a href="#canReadLineStdout">canReadLineStdout</a>(), <a href="#readyReadStdout">readyReadStdout</a>(), <a href="#readStdout">readStdout</a>() and <a href="#readLineStderr">readLineStderr</a>().

<h3 class=fn>QByteArray <a name="readStderr"></a>QProcess::readStderr ()<tt> [virtual]</tt>
</h3>
Reads the data that the process has written to standard error. When
new data is written to standard error, the class emits the signal
<a href="#readyReadStderr">readyReadStderr</a>().
<p> If there is no data to read, this function returns a QByteArray of
size 0: it does not wait until there is something to read.
<p> <p>See also <a href="#readyReadStderr">readyReadStderr</a>(), <a href="#readLineStderr">readLineStderr</a>(), <a href="#readStdout">readStdout</a>() and <a href="#writeToStdin">writeToStdin</a>().

<h3 class=fn>QByteArray <a name="readStdout"></a>QProcess::readStdout ()<tt> [virtual]</tt>
</h3>
Reads the data that the process has written to standard output. When
new data is written to standard output, the class emits the signal
<a href="#readyReadStdout">readyReadStdout</a>().
<p> If there is no data to read, this function returns a QByteArray of
size 0: it does not wait until there is something to read.
<p> <p>See also <a href="#readyReadStdout">readyReadStdout</a>(), <a href="#readLineStdout">readLineStdout</a>(), <a href="#readStderr">readStderr</a>() and <a href="#writeToStdin">writeToStdin</a>().

<h3 class=fn>void <a name="readyReadStderr"></a>QProcess::readyReadStderr ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the process has written data to standard error.
You can read the data with <a href="#readStderr">readStderr</a>().
<p> Note that this signal is only emitted when there is new data and not
when there is old, but unread data. In the slot connected to this signal, you
should always read everything that is available at that moment to make sure
that you don't lose any data.
<p> <p>See also <a href="#readStderr">readStderr</a>(), <a href="#readLineStderr">readLineStderr</a>() and <a href="#readyReadStdout">readyReadStdout</a>().

<h3 class=fn>void <a name="readyReadStdout"></a>QProcess::readyReadStdout ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the process has written data to standard output.
You can read the data with <a href="#readStdout">readStdout</a>().
<p> Note that this signal is only emitted when there is new data and not
when there is old, but unread data. In the slot connected to this signal, you
should always read everything that is available at that moment to make sure
that you don't lose any data.
<p> <p>See also <a href="#readStdout">readStdout</a>(), <a href="#readLineStdout">readLineStdout</a>() and <a href="#readyReadStderr">readyReadStderr</a>().

<h3 class=fn>void <a name="setArguments"></a>QProcess::setArguments ( const&nbsp;QStringList&nbsp;&amp;&nbsp;args )<tt> [virtual]</tt>
</h3>
Sets <em>args</em> as the arguments for the process. The first element in the list
is the command to be executed. The other elements in the list are the
arguments to the command. Any previous arguments are deleted.
<p> <p>See also <a href="#arguments">arguments</a>() and <a href="#addArgument">addArgument</a>().

<h3 class=fn>void <a name="setCommunication"></a>QProcess::setCommunication ( int&nbsp;commFlags )
</h3>
Sets <em>commFlags</em> as the communication required with the process.
<p> <em>commFlags</em> is a bitwise OR between the flags defined in <a href="#Communication-enum">Communication</a>.
<p> The default is <tt>Stdin|Stdout|Stderr</tt>.
<p> <p>See also <a href="#communication">communication</a>().

<h3 class=fn>void <a name="setPriority"></a>QProcess::setPriority ( int&nbsp;p )
</h3>
Sets the process priority to <em>p</em>, a value from -20 to 20,
where 0 is normal, lower values a give more favourable
priority, larger values less favourable.

<h3 class=fn>void <a name="setWorkingDirectory"></a>QProcess::setWorkingDirectory ( const&nbsp;QDir&nbsp;&amp;&nbsp;dir )<tt> [virtual]</tt>
</h3>
Sets <em>dir</em> as the working directory for a process. This does not affect
running processes; only processes that are started afterwards are affected.
<p> Setting the working directory is especially useful for processes that try to
access files with relative filenames.
<p> <p>See also <a href="#workingDirectory">workingDirectory</a>() and <a href="#start">start</a>().

<h3 class=fn>bool <a name="start"></a>QProcess::start ( QStringList&nbsp;*&nbsp;env = 0 )<tt> [virtual]</tt>
</h3>
Tries to run a process for the command and arguments that were specified with
<a href="#setArguments">setArguments</a>(), <a href="#addArgument">addArgument</a>() or that were specified in the constructor. The
command is searched in the path for executable programs; you can also use an
absolute path to the command.
<p> If <em>env</em> is null, then the process is started with the same environment as
the starting process. If <em>env</em> is non-null, then the values in the
stringlist are interpreted as environment setttings of the form <tt>key=value</tt> and the process is started in these environment settings. For
convenience, there is a small exception to this rule: under Unix, if <em>env</em>
does not contain any settings for the environment variable <tt>LD_LIBRARY_PATH</tt>, then this variable is inherited from the starting process;
under Windows the same applies for the enverionment varialbe <tt>PATH</tt>.
<p> Returns TRUE if the process could be started, otherwise FALSE.
<p> You can write data to standard input of the process with
<a href="#writeToStdin">writeToStdin</a>(), you can close standard input with <a href="#closeStdin">closeStdin</a>() and you can
terminate the process <a href="#tryTerminate">tryTerminate</a>() resp. <a href="#kill">kill</a>().
<p> You can call this function even when there already is a running
process in this object. In this case, QProcess closes standard input
of the old process and deletes pending data, i.e., you loose all
control over that process, but the process is not terminated. This applies
also if the process could not be started. (On operating systems that have
zombie processes, Qt will also wait() on the old process.)
<p> <p>See also <a href="#launch">launch</a>() and <a href="#closeStdin">closeStdin</a>().

<h3 class=fn>void <a name="tryTerminate"></a>QProcess::tryTerminate () const<tt> [slot]</tt>
</h3>
Asks the process to terminate. Processes can ignore this wish. If you want to
be sure that the process really terminates, you must use <a href="#kill">kill</a>() instead.
<p> The slot returns immediately: it does not wait until the process has
finished. When the process really exited, the signal <a href="#processExited">processExited</a>() is
emitted.
<p> <p>See also <a href="#kill">kill</a>() and <a href="#processExited">processExited</a>().

<h3 class=fn>QDir <a name="workingDirectory"></a>QProcess::workingDirectory () const
</h3>
Returns the working directory that was set with
<a href="#setWorkingDirectory">setWorkingDirectory</a>(), or the current directory if none has been
set.
<p> <p>See also <a href="#setWorkingDirectory">setWorkingDirectory</a>().

<h3 class=fn>void <a name="writeToStdin"></a>QProcess::writeToStdin ( const&nbsp;QByteArray&nbsp;&amp;&nbsp;buf )<tt> [virtual slot]</tt>
</h3>
Writes the data <em>buf</em> to the standard input of the process. The process may
or may not read this data.
<p> This function returns immediately; the QProcess class might write the data at
a later point (you have to enter the event loop for that). When all the data
is written to the process, the signal <a href="#wroteToStdin">wroteToStdin</a>() is emitted. This does
not mean that the process really read the data, since this class only detects
when it was able to write the data to the operating system.
<p> <p>See also <a href="#wroteToStdin">wroteToStdin</a>(), <a href="#closeStdin">closeStdin</a>(), <a href="#readStdout">readStdout</a>() and <a href="#readStderr">readStderr</a>().

<h3 class=fn>void <a name="writeToStdin-2"></a>QProcess::writeToStdin ( const&nbsp;QString&nbsp;&amp;&nbsp;buf )<tt> [virtual slot]</tt>
</h3> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> The string <em>buf</em> is handled as text using
the QString::local8Bit() representation.

<h3 class=fn>void <a name="wroteToStdin"></a>QProcess::wroteToStdin ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted if the data sent to standard input (via
<a href="#writeToStdin">writeToStdin</a>()) was actually written to the process. This does not
imply that the process really read the data, since this class only detects
when it was able to write the data to the operating system. But it is now
safe to close standard input without losing pending data.
<p> <p>See also <a href="#writeToStdin">writeToStdin</a>() and <a href="#closeStdin">closeStdin</a>().

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