Process to both write to and read from (pipe/fork)?

[Moved from R-help.]

One reason you cannot easily do this with basic R functions is that it is 
not portable.  E.g. pipes on Windows 98 do not work like that, and 
system() on that OS has to work hard to do something similar.

Ok, thanks -- I really thought (and hoped) that I was just overlooking
something obvious.

I'm not fully convinced that the portability issues necessarily
preclude providing the fork / pipe facilities, as there already is some
differentiation present now, reflected by capabilities(). In fact,
when I saw that availability of fifos is reflected by capabilities(),
I thought that then, more basic pipes must also be accessible somehow
(and spent some effort investigating this idea).

If we only had to consider standard Unices, pipe() would allow read-write 
modes.  As it is, it is easy for you to write an OS-specific extension.

Well, that is probably reasonably easy, but (not the least due to that
fact) I'm still surprised that it has not been done already. I can hardly
imagine that I'm the first one to want to use some external utility from
an R program in this way.

So, what do you R-devel folks do in this case, and what would you
recommend?

BTW, please re-read the distinction between R-devel and R-help in the 
posting guide: this (and most of your other recent postings) seem to me to 
fall unambiguously within the specification for R-devel.

At the time of writing, I thought I was asking for help in using R...

Best regards, Jan

+- Jan T. Kim -------------------------------------------------------+
 |    *NEW*    email: jtk@cmp.uea.ac.uk                               |
 |    *NEW*    WWW:   http://www.cmp.uea.ac.uk/people/jtk             |
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