[R] Pause in non-interactive mode

[Jonne Zutt]

Thank you very much, works perfectly!

I understand why as well now (thank you too Duncan ;))
I have been away from this mailinglist for a while, but I'm happy to
see that you are both still this active :)

Sorry for forgetting to mention my R version, it was
$ rpm -q R
R-2.10.1-1.fc12.i686

Jonne.

On Fri, Feb 5, 2010 at 10:45 AM, Prof Brian Ripley
<ripley at stats.ox.ac.uk> wrote:
> You have not told us your version of R.  In earlier versions of R readline()
> reads a line from the script (and input buffering affects which line: a
> number of packages fail their example checks on some platforms because of
> this).  In R-devel it returns "" immediately.
>
> To make this work you need to use Rscript, which distinguishes stdin() and
> "stdin".  Try out
>
> % Rscript foo.R
>
> where  foo.R is
>
> message("a")
> invisible(readLines("stdin", n=1))
> message("b")
>
> and see ?stdin and ?file for why it works.
>
> On Fri, 5 Feb 2010, Jonne Zutt wrote:
>
>> Dear all,
>>
>> I've found this nice code fragment on the web
>> (from Jan T. Kim if I'm correct):
>>
>> hitReturn <- function(msg)
>> {
>>        invisible(readline(sprintf("%s -- hit return", msg)));
>> }
>>
>> But it does not seem to work in non-interactive mode
>> ( I mean, when I start a script like this: R --vanilla < script.R )
>>
>> It simply continues, I guess the stdin is not connected?
>>
>> Does somebody know how to make it work.
>>
>> My script plots a few graphs (in X11 windows) and I don't want them to
>> disappear immediately.
>> A Sys.sleep(infinite) would probably work, but I thought there might
>> be a better solution?
>>
>> Thanks,
>> Jonne.
>
> --
> 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
>