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Executing iOS system code within R

6 messages · Christofer Bogaso, Marc Schwartz, elijah wright

Original
Christofer Bogaso
# 
Hi again,

I need to execute few line of system codes for iOS from R. Basically
that execution involves (as an example) :

1. Change the Working directory first
2. Execute some task (e.g.deleting a file)
3. Then go back to original folder/directory

I am aware of system() function which can be used here. However it
looks that system() function executes iOS code one-by-one i.e. after I
execute system('cd .....') for #1 above, that changed directory is not
passed for #2 and so on.

Is there any way where I can run a chain on iOS code as-a-whole using R.

Your help will be highly appreciated.

Thanks for your time.
elijah wright
# 
Did you mean macOS?  I am not aware of anything that can run both R
and iOS code - if there's some fancy thing out there that can, i would
like to know about that.  ;-)

--e


On Tue, Oct 10, 2017 at 12:58 PM, Christofer Bogaso
<bogaso.christofer at gmail.com> wrote:
Christofer Bogaso
# 
Yes macOS - High Sierra
On Tue, Oct 10, 2017 at 11:33 PM, elijah wright <elw at stderr.org> wrote:
Marc Schwartz
# 
I was kind of wondering that myself...given the frequent prior discussions here regarding running R on iOS... :-)

My recommendation would be to use R's built in file/folder/path related functionality, such as:

  ?getwd (which includes ?setwd)

  ?list.files

  ?file.info

  ?files

and other related functions listed under the "See Also" sections of those help pages.

You can use getwd() to store the current working directory in a vector, execute whatever system() level commands you need to, then restore the current working directory to the original:

  CurrDir <- getwd()

  system(YourSystemLevelCallsHere)

  setwd(CurrDir)



Regards,

Marc Schwartz
elijah wright
# 
something like:

system("PWD=`pwd`; cd TARGETDIR; ./runme.sh; cd $PWD') will do basically this.

Every time you run the system call it should be spawning a new shell
with a fresh environment.

--e


On Tue, Oct 10, 2017 at 12:58 PM, Christofer Bogaso
<bogaso.christofer at gmail.com> wrote:
Christofer Bogaso
# 
Hi Elijah, your suggestion is perfect - basically, I need to use ';'
as separator between multiple lines of iOS code. Thanks for this
pointer.
On Tue, Oct 10, 2017 at 11:46 PM, elijah wright <elw at stderr.org> wrote: