Re: improving performance of writing into a pipe

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On Monday, February 18, 2013 6:12:01 PM UTC, Michael Torrie wrote:
> On 02/18/2013 10:00 AM, mikprog@gmail.com wrote:
> 
> > [..]
> 
> >>
> 
> >> I don't see an exception in your answer. Where did you put it for us?
> 
> >>
> 
> > 
> 
> > well I just did print a message:
> 
> > 
> 
> >     PIPEPATH = ["/tmp/mypipe"]
> 
> > 
> 
> > [..]
> 
> >         try:
> 
> >             self.process = os.popen( self.PIPEPATH, 'w')
> 
> >         except:
> 
> >             print "Error while trying opening the pipe!"
> 
> >             print "check: ", self.PIPEPATH
> 
> >             exit()
> 
> > 
> 
> > I see the error messages.
> 
> 
> 
> Unfortunately your attempt to catch this exception is hiding the true
> 
> cause.  You need to give us the actual exception.  Otherwise it could be
> 
> anything from self.PIPEPATH not existing to who knows what.
> 
> 
> 
> Almost never do you want to catch all exceptions like you're doing.  You
> 
> should only catch the specific exceptions you know how to deal with in
> 
> your code.
> 
> 
> 
> For testing purposes, if your code really is as you put it, then
> catching exceptions is kind of silly since you're just re-raising the
> exception (sort of) but without any contextual information that would
> make the error meaningful.


Ok, I get your point.
But on the other hand how do I know what to catch if I have no clue what is causing the error?
There must be a way to catch all the possible errors and then investigate what is the problem, right? (which is not what I have done so far).

Or rather: what would you try to catch in this particular case?

Thanks

Thread

improving performance of writing into a pipe mikprog@gmail.com - 2013-02-18 07:12 -0800
  Re: improving performance of writing into a pipe Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-18 15:21 +0000
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-18 08:31 -0800
      Re: improving performance of writing into a pipe Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2013-02-18 17:49 +0100
        Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-18 09:00 -0800
          Re: improving performance of writing into a pipe Michael Torrie <torriem@gmail.com> - 2013-02-18 11:12 -0700
            Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 01:24 -0800
              Re: improving performance of writing into a pipe Peter Otten <__peter__@web.de> - 2013-02-19 10:55 +0100
                Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 02:27 -0800
                Re: improving performance of writing into a pipe Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-19 11:15 +0000
                Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 02:27 -0800
              Re: improving performance of writing into a pipe Michael Torrie <torriem@gmail.com> - 2013-02-19 10:47 -0700
                Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-20 09:54 -0800
                Re: improving performance of writing into a pipe John Gordon <gordon@panix.com> - 2013-02-20 18:39 +0000
                Re: improving performance of writing into a pipe Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-20 22:05 +0000
                Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-20 09:54 -0800
            Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 01:24 -0800
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-18 08:31 -0800
  Re: improving performance of writing into a pipe Serhiy Storchaka <storchaka@gmail.com> - 2013-02-18 21:29 +0200
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 04:10 -0800
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 04:10 -0800
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 05:39 -0800
      Re: improving performance of writing into a pipe Peter Otten <__peter__@web.de> - 2013-02-19 14:57 +0100
        Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 06:38 -0800
        Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 06:38 -0800
    Re: improving performance of writing into a pipe mikprog@gmail.com - 2013-02-19 05:39 -0800

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