[Rd] system(wait = FALSE)

Gabor Grothendieck ggrothendieck at gmail.com
Fri Feb 25 00:54:48 CET 2011


On Thu, Feb 24, 2011 at 2:46 PM, Oliver Soong <osoong+r at gmail.com> wrote:
> Sorry, I didn't know about r-windows at r-project.org.  Is that a public
> mailing list like r-help?  It's not listed under
> http://www.r-project.org/mail.html.
>
> I was able to reproduce the issue under two other 32-bit Windows 7
> machines, so it's not specific to the one computer.  It could be
> something common to my Windows user account configurations, although
> those accounts are not all configured similarly.  The part that's the
> strangest to me is that things do work when R is started through the
> start menu recent programs and when called from a command shell, but
> not through shortcuts or the start menu all programs list.  Sys.getenv
> does not indicate any particular difference.  Are there any other
> things I might check in R?

Right click the particular start menu recent program entry that starts
it and choose properties; also right click the shortcut and choose
properties and right click the start menu programs list entry and
choose properties.  See what the differences are in the targets.





>
> The actual command I want to run has quoting concerns (inherent to
> Windows and cmd) that force me to use system.  If you don't like cmd
> /c dir, this command also serves the purpose and also shows the weird
> behavior.  It presumes that Rscript is on the path:
> system("Rscript -e \"writeLines(letters,
> \\\"C:\\\\\\\\tmp\\\\\\\\tmp.txt\\\")\"", wait = FALSE)
>
> I've been told (and can see) that shell just calls system, and since
> the equivalent command in shell shows the same behavior due to this
> weirdness I'm finding with system, I decided to focus on what appeared
> to be the underlying problem (although perhaps not the actual problem
> if it is just something with me).
>
> Oliver
>
>
> On Wed, Feb 23, 2011 at 11:07 PM, Prof Brian Ripley
> <ripley at stats.ox.ac.uk> wrote:
>> On Wed, 23 Feb 2011, Oliver Soong wrote:
>>
>>> I'm having a very odd problem with system(wait = FALSE).  I'm not
>>> entirely sure whether it's a bug in R or a problem on our end.  It's
>>> related to a post a month or so ago in R-help which got no responses,
>>> but I have a little more to add.
>>
>> Well, the place you are asked to report issues on the Windows port is
>> R-windows at r-project.org.   But no one was able to reproduce this, and it
>> does sound as if the problem is on your specific machine.  If so, only you
>> can debug it and find out if it is really in R.
>>
>>> This command works as expected (I use c:\tmp since c:\ isn't normally
>>> writable under later versions of Windows).
>>
>> That's a bold claim (and untrue of my Windows 7 systems), but if c:\ is not
>> writeable, you cannot create c:\tmp!
>>
>>>  The file is created at
>>> c:\tmp\tmp.txt.
>>> system("cmd /c dir > c:\\tmp\\tmp.txt", wait = TRUE)
>>> This command does not work as expected.  There is no file created at
>>> c:\tmp\tmp.txt.
>>> system("cmd /c dir > c:\\tmp\\tmp.txt", wait = FALSE)
>>
>> Windows' own programs are peculiar things, and often do not obey Windows'
>> own rules for everyone else.  So I give little weight to such an example.
>>  And in any case, we recommend shell() for such usages.
>>
>>> The computer is a 64-bit Windows Server 2008R2 machine.  This affects
>>> R 2.12.1, both the 32-bit and 64-bit RGui executables but not the
>>> RTerm executables.  This does not affect 32-bit Windows XP, 32-bit
>>> Windows Server 2003, or 64-bit Windows Server 2008.  This does not
>>> affect R 2.12.0, and if I'm reading the svn logs correctly, there were
>>> some changes made to the system function from 2.12.0 to 2.12.1.
>>> Things seem to work normally when R is started from the start menu
>>> recent programs list, but things do not work properly when R is
>>> started from a shortcut, from the start menu all programs menu, or
>>> through explorer.
>>>
>>> I'm stumped.  Any ideas I can try?
>>>
>>> Oliver
>>>
>>> ______________________________________________
>>> R-devel at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>>
>>
>> --
>> 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
>>
>
>
>
> --
> Oliver Soong
> Donald Bren School of Environmental Science & Management
> University of California, Santa Barbara
> Santa Barbara, CA 93106-5131
> 805-893-7044 (office)
> 610-291-9706 (cell)
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>



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