[R] console from tcltk

[Gabor Grothendieck]

Thanks.  I've updated to the latest R on the mirror I used and
 puts stdout 12
from tcl does indeed produce output from Rterm on Windows but gives an
error message from Rgui on Windows (both on Windows Vista SP1).

----------------- this works

C:\tmp2>Rterm

R version 2.7.0 Patched (2008-05-11 r45672)
[...deleted...]
> library(tcltk)
Loading Tcl/Tk interface ... done
> .Tcl("puts stdout 12")
12
<Tcl>
> xx <- .Tcl("puts stdout 12")
12

-------------- this gives an error message

C:\tmp2>Rgui

R version 2.7.0 Patched (2008-05-11 r45672)
[...deleted...]
> library(tcltk)
Loading Tcl/Tk interface ... done
> xx <- .Tcl("puts stdout 12")
Error in structure(.External("dotTcl", ..., PACKAGE = "tcltk"), class
= "tclObj") :
  [tcl] can not find channel named "stdout".


On Wed, May 14, 2008 at 11:09 AM, Prof Brian Ripley
<ripley at stats.ox.ac.uk> wrote:
> I assume by 'console' you mean the Rgui window.  That is not where stdout is
> connected -- it is not a file.  As the CHANGES file for 2.7.0 says
>
>    o   When Rgui is launched from a terminal, C output from ill-formed
>        packages that write to stdout or stderr rather than use
>        Rprintf will appear in the terminal rather than being lost.
>        (Only on XP or later.)  This can be very handy for debugging C
>        code in packages: just write debugging messages to stdout.
>
> And indeed that is what your example does.  It also writes to the terminal
> from Rterm.
>
> Tcl is no different from any other C-based add-on in this respect.
>
> Note though that system() does provide a way to capture stdout to the Rgui
> window, so you can probably run tcl scripts via the tcl shell and capture
> their output.
>
> On Tue, 13 May 2008, Gabor Grothendieck wrote:
>
>> Is it possible to use the console from within tcltk?
>>
>>> library(tcltk)
>>> tcl("puts", "stdout", "Hello, World")
>>
>> Error in structure(.External("dotTclObjv", objv, PACKAGE = "tcltk"),
>> class = "tclObj") :
>>  [tcl] can not find channel named "stdout".
>>>
>>> .Tcl('puts stdout "Hello, World"')
>>
>> Error in structure(.External("dotTcl", ..., PACKAGE = "tcltk"), class
>> = "tclObj") :
>>  [tcl] can not find channel named "stdout".
>>>
>>> R.version.string  # Windows Vista
>>
>> [1] "R version 2.7.0 RC (2008-04-17 r45367)"
>
> Oh dear, not even the released version!  Please update as the posting guide
> asked you to do before posting.
>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
> --
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>