Ctrl-C with R.exe and Rterm.exe in R v1.9.0
On Thu, 6 May 2004, Henrik Bengtsson wrote:
-----Original Message----- From: r-devel-bounces@stat.math.ethz.ch [mailto:r-devel-bounces@stat.math.ethz.ch] On Behalf Of Duncan
Murdoch
Sent: den 6 maj 2004 16:16 To: Henrik Bengtsson Cc: r-devel@stat.math.ethz.ch Subject: Re: [Rd] Ctrl-C with R.exe and Rterm.exe in R v1.9.0 On Wed, 5 May 2004 12:57:29 +0200, "Henrik Bengtsson" <hb@maths.lth.se> wrote :
Ctrl-C works as expected. Exiting R and you're back at a "clean" prompt. Now, try the same thing with R.exe (from a restarted
prompt):
C:\Program Files\R>rw1090\bin\R.exe --vanilla --quiet
^C ^C 1+1
[1] 2
Sys.sleep(100)
^C C:\Program Files\R>
Strange things happen. R seems still to be running but has
at the same
time returned(?) the control back to the Command prompt.
Yes, that is indeed strange behaviour. Ctrl-C definitely presents problems. For instance, on my WinXP system running R from a Cygwin prompt, a Ctrl-C during the Sys.sleep kills Rterm, whereas under the Windows cmd.exe prompt it works properly as it did for you.
Cygwin is indeed where I noticed the problem first. For Cygwin, I know that Ctrl-C did not kill Rterm on R v1.7.1 and before, but from R v1.8.1 (don't know about R v1.8.0) it all of a sudden started to do it. Maybe there is a clue somewhere in the diff's between v1.7.1 and v1.8.x, which may also explain what is going on in R.exe and Rterm.exe.
No, as it was to do with a change in the MinGW runtime system and not in R. Expecting to be able to use ^C as a Windows signal in a shell that is emulating Unix is I think unrealistic. ^C in Rterm does work in tcsh.exe, cmd.exe and various clones. It is becoming a mantra, but *** Cygwin is not Windows *** and R is a Windows and not Cygwin executable. People who want a Cygwin port of R perhaps should work on one ....
Brian D. Ripley, ripley@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