[Rd] Determining files opened by an R session

[Martin Gregory]

I'm using R in a regulated environment and one of the requirements is to 
be able to trace how a result is arrived at. I would like to be able to 
determine which files are opened in read or write mode by an R session, 
for example when a program uses source, sink, file, open, read.table, 
write.table or any of the other functions which can be used to read or 
write files. I'm also interested in output to graphics devices.

I've looked in the documentation but only found information relating to 
profiling. Looking through the source code it seems that much file i/o 
is done via the C functions *_open in main/connections.c but don't see 
anything there that looks like logging.

Could someone let me know if it is possible to log which files are opened?

Regards,
Martin Gregory