[Rd] How does R handle interrupts?

[Zhou Fang]

Hi,

I wonder if anyone can clear some things up for me to help me read the
R source code.

Suppose R receives SIGINT whilst processing R code... Where is that
handled? What gets called?

If you have R >source a script, where is that script stored? How does
R keep track of where it is in the script?

My overall goal is to find out if there's a way somehow so that on a
signal, R could be made to modify, possibly temporarily the script it
is currently executing in an useful way, by, say, inserting
'browser()' at the next convenient point, or running an user-set
function, or something. Unless there's some reason why allowing this
is a very bad idea?

Thanks for any help that can be provided.

Zhou Fang