R help - Dec 2011 - maximum number of files to choose with tk_choose.files ?

Dear R-list,

I am running a script in which I calculate and create new
files from orginal ones.
As I have a large number of files to process, I automatize
this calculation with a loop.

First, I am choosing the files to work with.
This is done by using:

Files <- if(interactive()) tk_choose.files(default
paste(getwd(),"/", sep=""), filter = Filters, multi=TRUE,
caption = "Files to process")

It works ok but if I am choosing approximately less than
350-400 files.
If I want to choose more files, it is not working.

Some additional information:
Files are 5kb big.
R version 2.12.1
memory.limit 4000

Someone have an idea if the function tk_choose.files
recognizes a maximum of files to work with?

thanks and greetings,
Cristabel.


Cristabel Dur?n Rangel. PhD Student.
Institute of Silviculture. Faculty of Forest and
Environmental Sciences. University of Freiburg.
Germany
Telf: +49 (761) 203 8604 (ofc) 

?Man lernt die Physiognomie einer Landschaft desto besser
kennen, je genauer man die einzelnen Z?ge auffa?t, sie
untereinander vergleicht und so auf dem Wege der Analysis
den Quellen der Gen?sse nachgeht, die uns das gro?e
Naturgem?lde bietet.?
				Alexander von Humboldt, 1799