subprocess.popen question

Eric_Dexter at msn.com Eric_Dexter at msn.com
Fri Jun 22 15:08:49 CEST 2007


On Jun 22, 12:10 am, "Gabriel Genellina" <gagsl-... at yahoo.com.ar>
wrote:
> En Fri, 22 Jun 2007 01:05:36 -0300, Eric_Dex... at msn.com  
> <Eric_Dex... at msn.com> escribió:
>
>
>
>
>
> >> >> >> cmd = ["gawk", "-f", "altertime.awk", "-v", "time_offset=4", "-v",
> >> >> >> "outfile=testdat.sco", "i1.sco"]
> >> >> >> output = subprocess.Popen(cmd,
> >> >> stdout=subprocess.PIPE).communicate()[0]
> >> >> >> lines = output.splitlines()
> >> >> >> for line in lines:
> >> >> >>    print line
>
> >> >> >  C:\dex_tracker\pipe1.py
> >> >> > Traceback (most recent call last):
> >> >> >  File "C:\dex_tracker\pipe1.py", line 14, in
> >> >> > last_line = subprocess.Popen([cmd],
> >> >> > stdout=subprocess.PIPE).communicate()[0]
> >> >> >  File "C:\Python25\lib\subprocess.py", line 593, in __init__
> >> >> > errread, errwrite)
> >> >> >  File "C:\Python25\lib\subprocess.py", line 793, in _execute_child
> >> >> > startupinfo)
> >> >> > WindowsError: [Error 2] The system cannot find the file specified
> >> >> > Script terminated.
>
> >> >> > I can write it out as a batch file and then run it but that is a  
> >> messy
> >> >> > hack..
>
> >> >> If cmd is a list of arguments, like the example above, you should use
> >> >> subprocess.Popen(cmd,...) (like the example above, too).
>
> >> > I had cut and pasted the example in to get that error...  could it be
> >> > a problem with ms windows??? (I am at a library computer befour work
> >> > so that ended my testing)
>
> >> Note the call to subprocess.Popen- is the first argument [cmd] or cmd?
> >> What do you get with print repr(cmd)?
> >> Do you have gawk installed on that machine too?
>
> > gawk is installed..  I do fine when I just call gawk I get all the
> > options to use with it but the minute I try to use the options with it
> > I have problems.  I have done it with batch files but then I would
> > have to write out a batch file and then run the batch file.  seems
> > like more work than I should have to do to use options with a command
> > line program..  I have done this in other cases with os.startfile and
> > other cases and would like to fix it.
>
> Ok, but please check *what* are the arguments toPopen. If cmd is a *list*  
> as shown on the first quoted line on this message, you should call  
> subprocess.Popen(cmd, ...) as shown on the third line on this message, but  
> your traceback shows that you are usingPopen([cmd], ...)
> Can you see the difference?
>
> --
> Gabriel Genellina- Hide quoted text -
>
> - Show quoted text -

I seemed to have it working sorta when I run it and save the results I
am noticing that in spe it spaces correctly but when I save it to a
file I can open it in wordpad there is only one line.  when I open in
up in WinXound (A csound editor) it is double spaced.  if I do it in a
batch file the output file is spaced correctly..  when I do splitlines
it is giving me one charecter down the page as output..  Do I need to
do something or can I do something to put an end of line charecter in
the output??




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