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Subject: Re: improving performance of writing into a pipe
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Xref: csiph.com comp.lang.python:39194

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