[Newbies] Reading context from UnixProcess

[Jim O'Connor]

On Mon, 2008-04-07 at 16:30 -0400, David T. Lewis wrote:
> On Sun, Apr 06, 2008 at 10:47:29PM -0600, Jim O'Connor wrote:
> > I'm having trouble figuring out how to collect input from an externally
> > executed linux process. 
> > 
> > The simple example below should, I think let me dump the contents 
> > of the directory /etc.  The stream type returned by initialStdOut is
> > AttachableFileStream.  Sending the contents message to it generates
> > a primitive error, caused I think because the stream's instance variable
> > position turns out to be nil on inspection.
> > 
> > p := UnixProcess command: 'ls -l /etc/'
> > s := p initialStdOut
> > s contents
> > 
> > What am I doing wrong or missing?
> > 
> > Better would be if someone has a simple code snippet the executes an
> > external process and then accepts output from it asynchronously.
> 
> 
> Jim,
> 
> A good way to do this is to use a PipeableOSProcess, which provides a
> higher-level wrapper around the UnixProcess and takes care of setting
> up all the pipes between Squeak and the external process. You will
> need to load the CommandShell package in addition to the OSProcess
> package in order to get this.
> 
> Once you have loaded CommandShell, try inspecting this expression:
> 
> 	ProxyPipeline command: 'ls -l /etc'
> 
> You can read the command output directly from the resulting
> PipeableOSProcess instance.
> 
> I am not near a Squeak computer at the moment, so apologies in advance
> if I have misremembered the details above. In any case, you will find
> a number of examples on the class side of ProxyPipeline and a few of
> the other classes in CommandShell and OSProcess.
> 
> HTH,
> 
> Dave
> 
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Dave,

Thanks.  That's just what I was looking for.

Jim