[Tutor] subprocess & pyw conflict ?

[Dave S]

On Thursday 07 December 2006 00:31, Luke Paireepinart wrote:
> Dave S wrote:
> > Hi all,
> >
> > I thought I had my solution with subprocess ... my test code ...
> >
> >
> >
> > #!/usr/bin/env python
> > # -*- coding: iso8859_1 -*-
> >
> > import subprocess
> >
> > a = subprocess.Popen('tasklist.exe', bufsize=0, stdout=subprocess.PIPE,
> > universal_newlines=True)
> > op = a.stdout.readlines()
> >
> > for i in op:
> >     if i.split(' ')[0] == 'gmanager.exe':
> >         f = open('E:\Documents and Settings\All
> > Users\Desktop\gsr_running', 'w')
> >         f.close()
> >
> >
> >
> > works a treat when I run it as proc.py detects the process I am looking
> > for & writes a dummy file to the desktop. :) but I get a black windows
> > terminal flash up.
> >
> > The code will eventually run in an app.pyw so to check it would be OK I
> > renamed my working proc.py to proc.pyw - it fails :(, No window (as
> > expected), no dummy file (not expected) - the process gmanager.exe is
> > running.
> >
> > So there seems to be a problem with subprocess & pyw
> >
> > Googling I found ...
> > https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1358527&grou
> >p_id=5470 So I tried the suggested workaround with proc.pyw ...
> >
> >
> >
> > #!/usr/bin/env python
> > # -*- coding: iso8859_1 -*-
> >
> > import subprocess
> >
> > a = subprocess.Popen('tasklist.exe', bufsize=0, stdin=subprocess.PIPE,
> > stdout=subprocess.PIPE, universal_newlines=True)
> > op = a.stdout.readlines()
> > a.stdin.close()
> >
> > for i in op:
> >     if i.split(' ')[0] == 'gmanager.exe':
> >         f = open('E:\Documents and Settings\All
> > Users\Desktop\gsr_running', 'w')
> >         f.close()
> >
> >
> > Still zip, and because there is no terminal, I cannot view any errors !
> >
> > Any suggestions welcome :)
>
> Well, because I'm batting 0 on this thread so far, I think I'll just go
> ahead and suggest another bad solution!
> You could try redirecting the output of sys.stderr to a file, and you
> might be able to see the error message! :D
>
> If you hadn't said 'any suggestions welcome' I might've kept this to
> myself :P

Ahhh .. 'any suggestions' is an SOS call - all any any ideas are warmly 
greeted :)


>
>  >>> import sys
>  >>> class TestClass(object):
>
>     def __init__(self):
>         self.data = []
>     def write(self,item):
>         self.data.append(item)
>
>  >>> a = TestClass()
>  >>> sys.stderr = a
>  >>> salfjdsljfka321423
>  >>> print a.data
>
> ['\nTraceback (most recent call last):', '\n', '  File "<pyshell#14>",
> line 1, in -toplevel-\n', '    salfjdsljfka321423\n', "NameError: name
> 'salfjdsljfka321423' is not defined\n"]
>
> Except instead of a file-like class, you could just use a real file.
> But then it would only leave the last line intact.
> So you'd probably want to make a class that wraps a file object, where
> the write method just appends to an internal list,
> and it writes it all out to the file when you call the Class.close() or
> whatever.
> Actually, I guess the program stops executing on an exception...
> Hmm, not really sure what you'd do exactly.
>
>
> Sure, there are better solutions, and this doesn't really help you with
> your original problem, but it at least lets you see your error message!
> HTH,
> -Luke

Thanks for that - I will give it a go & post back :)

>
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