From: Simon Strandgaard <0bz63fz3m1qt3001@...>
Date: 2003-05-11T01:47:46+09:00
Subject: Re: capture output

On Sun, 11 May 2003 02:17:14 +0900, Brian Candler wrote:

> On Sat, May 10, 2003 at 06:45:36PM +0900, Simon Strandgaard wrote:
>> In rubys source for "io.c" there is a bunch of WIN32 checks 
> ..
>> The first 4 of them seems OK.. the rest of them is where I see 
>> that windows requirs special attention. Windows is wierd.
> 
> It is, but Ruby has coded around those things, so you don't have to worry
> about them. To me that's one of the big advantages of a high-level platform
> like Ruby: one person solves the problem once and then your code works the
> same.

Remember im living in a zone between Ruby and C++.. I am a little worried 
about supporting windows myself.


>> Further more I want to be able to run my favorite ruby-scripts unmodified.
>> Example: rubyunit outputs to stdout/stderr.
> 
> Bad example, because they've thought of that already. If you run it from the
> command line then yes it outputs to stdout/stderr, because you are invoking
> the command-line runner; but it has many different runner interfaces. If you
> run it using the GTk interface, then it outputs to GTk windows, and it also
> has a FOX interface. Look in

I only tried the console frontend.. This sounds nice.. I must try out the
GUI. I am sorry that I cannot provide you with any good example.
 

> In general, if I wanted to run some program which interacted over
> stdin/stdout, but I wanted that interaction to occur inside a GUI window, I
> would create a window, fork and exec a child, and talk to it over pipes, so
> that I could capture keystrokes and send them down stdin, and capture stdout
> and stick it on the screen as it was generated.

Remember that im sharing classes with those programs (c++ <=> ruby),
marshalling it over a pipe would be slow (but I have no evidence here). 
What you talking about is a ruby-jail ;-)

 
>> >   A. If you don't mind mixing the child's stdout and stderr, you might just
>> >      get away with using shell redirection:
>> >            string = `someprog args 2>&1`
>> 
>> This is the answer I have bumped into most-frequently on google.
>> BTW: isn't this kind of redirection shell-specific (tcsh, zsh, ksh).
> 
> Yes. Ruby uses /bin/sh by default, so it's not unreasonable to assume
> /bin/sh semantics. You might be able to configure it differently. But I
> agree with you, I'd certainly be happier asking Ruby to dup fd1 and fd2 to
> the same pipe, than using '2>&1'.

rock n roll.. 

 
>> Look at the "Exception Handling" section and tell me what you think:
>> http://metaeditor.sf.net/embed/
> 
> Looks pretty good to me, I'm not a C++ programmer though so I can't comment
> on the mapping between exceptions.

Thanks.. there is still much on the TODO for the tutorial and there
is still many things I must try out in practice.
Then it hopefully will become a really good tutorial :-)

--
Simon Strandgaard