[open] Error when using External Runner on Mac OS

pythonpoole

I'm encountering a problem when I try to run any experiment using the External (opensesamerun) runner. An Unexpected Error immediately pops up as soon as I try to run an experiment:

Unexpected error
exception message: 
exception type: OSError

Traceback (also in debug window):
  File "/Applications/OpenSesame.app/Contents/Resources/lib/python2.7/libopensesame/exceptions.py", line 109, in __init__
IndexError: list index out of range

I'm running this on Mac OS X 10.10.1 (Yosemite). This error can be reproduced on other Macs. It doesn't matter what experiment you run, nor does it matter whether you run it normally or as a quick run experiment.

This issue is non-critical since the inprocess runner can be used instead, but I would appreciate any insight into what may be causing the error. Presumably using the external runner would be preferable when you consider that it allows the experiment to hang/crash without affecting the OpenSesame experiment builder.

sebastiaan

Hi,

What happens here is that OpenSesame tries to parse an Exception (i.e. a Python error) into a readable format, but this goes wrong. So what you're seeing is an Exception that occurs while parsing another Exception, if you see what I mean. Not very informative for the underlying problem.

But this is an old issue that should not occur in recent versions of OpenSesame. What version are you running? The latest Mac OS package is not yet on the documentation page, but you can get it from here:

• http://ems.psy.vu.nl/opensesame/

The experiment will probably still crash, but at least you can see why.

Cheers!
Sebastiaan

pythonpoole

Thanks Sebastiaan, but I still have the same problem.

I was running 2.9.5, but I upgraded to 2.9.6 and I still have the same issue.

Regardless of what experiment I run (even the built-in template experiments), the runner will crash immediately with the same error whenever I use the opensesamerun option.

The error is as follows (looks to be the exact same as before).

Unexpected error
exception message: 
exception type: OSError

Traceback (also in debug window):
  File "/Applications/OpenSesame.app/Contents/Resources/lib/python2.7/libopensesame/exceptions.py", line 109, in __init__
IndexError: list index out of range

Daniel

Hi pythonpoole,
I don't think it's possible to run experiments with the external runner when using the app version of opensesame. The reason is that opensesamerun is embedded in the OpenSesame.app itself which is kind of a zip file on OSX (i.e. seen as a package). You could see if you could set the runner location to OpenSesame.app/Contents/Resources/opensesamerun, but I doubt this will work...
I hope to have the multiprocess runner also working one day on the mac again, but for now it seems impossible...

sebastiaan

@dschreij But--aside from the fact that the external runner doesn't work--what puzzles me is how this particular error message can occur. As you can see, it arises from a piece of code that's within a try ... except ... clause.

• https://github.com/smathot/OpenSesame/blob/master/libopensesame/exceptions.py#L109

So it should be caught. And that's what made me think that an old version OpenSesame was being used. Any idea? Can you reproduce this error on Mac OS?

earcanal

I'm also interested in using opensesamerun on OS X. Could you clarify something, if I try to do this using (for example) one of the zip packages on http://ems.psy.vu.nl/opensesame/, will I also need to install all of the OS X dependencies?

sebastiaan

Could you clarify something, if I try to do this using (for example) one of the zip packages on http://ems.psy.vu.nl/opensesame/, will I also need to install all of the OS X dependencies?

No, the Mac OS package is standalone, just the like windows packages. The dependencies are only relevant when you want run OpenSesame from within your own Python environment.

earcanal

When I ran opensesamerun it reported that yaml wasn't installed. I installed it but then seemed to be missing a further dependency (the point at which I stopped and posted here). I wonder what I was doing wrong?

Daniel

Strange, someone else emailed me about this question before, but I couldn't reproduce it. It also puzzled me that this occured even though that statement is within a try/catch block. The Python version used in the latest OSX release (2.9.6) is 2.7.10, so that can't be it.

How do the people here use opensesamerun? do they use the version that is included in the app, or are they running OpenSesame from source?

earcanal

I unzipped http://ems.psy.vu.nl/opensesame/OpenSesame_portable-2.9.5-new-psychopy.zip and then ran OpenSesame/opensesamerun (after removing dos line endings). Is this a Windows package?!!

sebastiaan

Is this a Windows package?!!

Nope, that's the Mac OS package. But my guess is that opensesamerun simply doesn't work in this Mac OS package. @dschreij can you confirm this?