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<font size="-1"><font face="Bitstream Vera Sans">Dear PyKDE Members<br>
<br>
I'm opening a new QThread which launches a command-line archiver (7z)
in a QProcess (called 'pArc').<br>
<br>
I'm using following code block within that thread:<br>
</font></font>
<blockquote><font face="Bitstream Vera Sans Mono" size="-1">while not
pArc.waitForFinished(250) :</font><font face="Bitstream Vera Sans Mono"><br>
</font><font face="Bitstream Vera Sans Mono" size="-1"> if
pArc.waitForReadyRead(100) :</font><font face="Bitstream Vera Sans Mono"><br>
</font><font face="Bitstream Vera Sans Mono" size="-1">
sArcData = QtCore.QString(pArc.readData(512))</font><font
face="Bitstream Vera Sans Mono"><br>
</font><font face="Bitstream Vera Sans Mono" size="-1"> print
"Output = " + str(sArcData)</font><font face="Bitstream Vera Sans Mono"><br>
</font><font face="Bitstream Vera Sans Mono" size="-1"> else :</font><font
face="Bitstream Vera Sans Mono"><br>
</font><font face="Bitstream Vera Sans Mono" size="-1"> print
"Nothing"</font><font face="Bitstream Vera Sans Mono"><br>
</font></blockquote>
<font size="-1"><font face="Bitstream Vera Sans"><br>
While the (large) files are being archived, "Nothing" is printed to the
screen several times. When the process is finished, "Output = ..." is
then printed. However, I know that 7z prints data to its stdout while
the archiving process is happening (i.e. it doesn't just wait until it
has finished). I want to update a QProgressBar based on the output
from 7z, so I can't wait until it has finished otherwise this defeats
the purpose of the QProgressBar.<br>
<br>
</font></font><font size="-1"><font face="Bitstream Vera Sans">The
PyQt4 documentation has this to say:<br>
</font></font>
<blockquote><font size="-1"><font face="Bitstream Vera Sans">You also
have the option of forwarding the output of the running process </font></font><font
size="-1"><font face="Bitstream Vera Sans">to the calling, main
process, by passing ForwardedChannels as the argument.</font></font><br>
<br>
<font size="-1"><font face="Bitstream Vera Sans">QProcess.ForwardedChannels:
QProcess forwards the output of the running </font></font><font
size="-1"><font face="Bitstream Vera Sans">process onto the main
process. Anything the child process writes to its </font></font><font
size="-1"><font face="Bitstream Vera Sans">standard output and
standard error will be written to the standard </font></font><font
size="-1"><font face="Bitstream Vera Sans">output and standard error
of the main process.</font></font><br>
</blockquote>
<br>
<font size="-1"><font face="Bitstream Vera Sans">So, I then added this
line before the above code block:<br>
</font></font>
<blockquote><font face="Bitstream Vera Sans Mono" size="-1">pArc.setReadChannelMode(QtCore.QProcess.ForwardedChannels)</font><br>
</blockquote>
<font size="-1"><font face="Bitstream Vera Sans"><br>
While the file is being archived, I can now correctly see the standard
output being progressively printed to the screen. But how do I read
this output since it is no longer associated with my QProcess? How</font></font><font
size="-1"><font face="Bitstream Vera Sans"> do I access the standard
output of this 'main' process?<br>
<br>
Thanks for your help.<br>
<br>
<br>
Chris<br>
<br>
</font></font>
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