[Vm-dev] different behaviour for Carbon VM depending on how it's started

David T. Lewis lewis at mail.msen.com
Fri May 2 10:41:53 UTC 2008

On Fri, May 02, 2008 at 09:15:45AM +0200, Michael Haupt wrote:
> Hi David,
> On Fri, May 2, 2008 at 4:48 AM, David T. Lewis <lewis at mail.msen.com> wrote:
> >  I'm pretty sure we are not going to be able to blame this one on the VM ;-)
> I totally agree. It looked like it at first sight.
> >   (CommandShell pipeline: 'python /path/to/script.py -some -args') errorUpToEnd inspect
> That looks like a good starting point for further debugging... thanks.
> Have you noticed my later e-mails in this thread? Do the details
> mentioned there make any sense to you?

Well, I'd only be guessing (and I don't have a Mac to try it on), so
I can't really say. But there is a pretty good chance that /bin/sh
is printing an error message on its stderr, and you just can't see
it (I don't know where stderr ends up when you run Squeak on a Mac,
but I assume it's going someplace that you don't see). If you run
it with CommandShell, the stderr will be piped back into Squeak
where you can look at it.

Some other tips for debugging:

- When you run the python command line with CommandShell, you actually
will *not* be using /bin/shell to run Python. Instead, the work
of /bin/sh is done in Smalltalk, thus it's possible that the
behavior might be a little different.

- It also is convenient to just open up an interactive ComandShell
window (world menu -> open... -> Squeak shell) and enter your
"python /path/to/script.py -some -args" command directly into the
shell window. Any error messages would be shown in the window.

- One more variant of the expressions for debugging:
  (CommandShell pipeableProxyFor: 'python /path/to/script.py -some -args') value errorUpToEndOfFile.


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