Redirection problem

[Gabriel Genellina]

En Mon, 23 Apr 2007 13:10:55 -0300, CSUIDL PROGRAMMEr  
<syedamjad_a at yahoo.com> escribió:

> I am new to python. so be patient with me
>
> I am trying to redirect the output of os.popen command to a file. I
> want to append to that file. but instead of appending. The file only
> shows last command that was writtenn to  it.
>
>
>
>  filehandle= open("/root/yhpc-2.0/installer/yhpc-log" ,"a+");
>     filehandle.write(" Command executed is " + cmd);
>     try:
>       pipe= os.popen('%s > /root/yhpc-2.0/installer/yhpc-log' %cmd );
>     except : IOError;
>   filehandle.close();

There are two ways to redirect the output:
- using the shell, with > and >>
- using popen
You are mixing both here. Your command line uses >xxx-log, thus efectively  
overwriting any previous content on the log file. You could do this:


logfile = open("....", "a+)
logfile.write("Command: %s\n" % cmd)
pipe = os.popen(cmd)
for line in pipe:
   logfile.write(line)
pipe.close()
logfile.close()

Or try the subprocess module.

-- 
Gabriel Genellina