R devel - Oct 2005 - Socks under R

Hi

when I use

con1 <- socketConnection(...)

in R and want to send text from another application written in Delphi to 
R, do I just have to send the text or do I have to implement more 
control characters and so on?
Is

con1 <- socketConnection(port=6011, server=TRUE)
writeLines("plot(rnorm(100))", con1)

just sending the text in "plot(rnorm(100))" to the socket or is it
doing
more (R specific protocoll for socks comminication)?

Thanks,

Rainer


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Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation
Biology (UCT)

Department of Conservation Ecology
University of Stellenbosch
Matieland 7602
South Africa

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email:	RKrug at sun.ac.za
       	Rainer at krugs.de

Rainer,

On Oct 19, 2005, at 3:29 PM, Rainer M. Krug wrote:
> when I use
>
> con1 <- socketConnection(...)
>
> in R and want to send text from another application written in  
> Delphi to  R, do I just have to send the text or do I have to  
> implement more control characters and so on?
Sockets are just reliable bi-directional communication channels (in  
the default mode), so their use is entirely up to you (both on R side  
and other application's side).
> Is
>
> con1 <- socketConnection(port=6011, server=TRUE)
> writeLines("plot(rnorm(100))", con1)
>
> just sending the text in "plot(rnorm(100))" to the socket or is
it
> doing more (R specific protocoll for socks comminication)?
It basically equivalent to using "send" on the socket API level [i.e.
the above effectively does send(s, "plot(rnorm(100))\n", 17, 0)], so  
it's up to the other side to receive it properly. There is no "R  
specific protocol" - socket connections in R use regular TCP (neither  
red nor white "socks" ;)), so the literature on socket programming is
your friend (e.g. using readLines(con1) for incoming traffic in your  
example would be a bad idea).

Cheers,
Simon