[Rd] existence of easy example of .Call??

[Freja.Vamborg at astrazeneca.com]

Dear R-develers,

I have been seraching in vain for an example of source-code, using .Call, to
call an R-function from within C.
Am also wondering i this .Call command works for all functions, say if I
write a function analyse<-function()
within my R functoin, can this function be called by the c-code called later
in the same function.

Eg, 

my.function<-function(){
...

analyse<-function() {}

result<-.Call("My.c.code",...)
}

I then want My.c.code to call, analyse..

I have read the R-extension manual, but am just wondernig if anyone has
another example of use of .Call, which may be more clear to a beginning
user.
Many thanks in advance, 
Freja