Re: Weird issue, command output unable to pipe or capture

If you set PYTHONUNBUFFERED=1 in your env before running python, it'll
turn off that output buffering.

On Thu, 2018-04-19 at 11:32 -0700, kevin dankwardt wrote:
> Caching/buffering stderr sounds pretty unfortunate and inconvenient.
> 
> On Thu, Apr 19, 2018 at 11:28 AM, Steve Litt <[email protected]
> om> wrote:
> > When using |& to pipe stderr and stdout to the same place, be
> > careful
> > not to assume anything about order in the merged stream. Python 3
> > has
> > all sorts of caching so that stderr is outputted later than you'd
> > think
> > it would be.
> > 
> > SteveT
> > 
> > 
> > On Thu, 19 Apr 2018 10:40:11 -0700
> > kevin dankwardt <[email protected]> wrote:
> > 
> > > |&  is also handy so that stdout and stderr both go into the
> > pipe.
> > > 
> > > as an example
> > > 
> > > $ strace -e open ls |& grep /lib
> > > 
> > > 
> > > 
> > > On Thu, Apr 19, 2018 at 8:53 AM, Robert Freiberger
> > > <[email protected]> wrote:
> > > 
> > > > That works!
> > > >
> > > > So I never knew that you could route the stderr after the > to
> > a
> > > > file. I'm going to refresh my knowledge of stdout and stderr
> > but I
> > > > was able to capture the output in a variable by using the
> > foo=$(foo
> > > > 2>&1). I honestly don't think I've encountered this before.
> > > >
> > > > Thanks again!
> > > >
> > > > On Wed, Apr 18, 2018 at 9:07 PM Lister <[email protected]
> > m>
> > > > wrote: 
> > > >>
> > > >>
> > > >> On 04/18/2018 09:01 PM, Robert Freiberger wrote:  
> > > >> > Hello,
> > > >> >
> > > >> > I've stumbled across a strange issue and wasn't sure if I'm
> > > >> > overlooking something very simple. The problem is at work we
> > > >> > have an application written in Ruby which is a wrapper for
> > Chef
> > > >> > knife command. It's pretty much taking the Chef environments
> > > >> > from our Chef org and building a set of arguments.
> > > >> >
> > > >> > For example:
> > > >> >
> > > >> > $ foo dev-stage1 list
> > > >> >
> > > >> > This would use the Chef knife command to query the hosts in
> > the
> > > >> > dev-stage1 environment and list them out. The problem is the
> > > >> > output does not allow me to pipe or capture in a bash
> > variable
> > > >> > "foo=$(foo dev-stage1 list)". Even something like "$ foo
> > > >> > dev-stage1 list > /tmp/foo" doesn't work either.  
> > > >> Are you sure the command does not output to stderr?
> > > >> You may try
> > > >> $ foo > /tmp/foo 2>&1
> > > >>
> > > >> thanks
> > > >> K
> > > >>  
> > > > --
> > > > Robert Freiberger
> > > > 510-936-1210
> > > >
> > > > _______________________________________________
> > > > svlug mailing list
> > > > [email protected]
> > > > http://lists.svlug.org/lists/listinfo/svlug
> > > >
> > > >  
> > > 
> > > 
> > 
> > _______________________________________________
> > svlug mailing list
> > [email protected]
> > http://lists.svlug.org/lists/listinfo/svlug
> 
> 
> 
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