"attach" in R corr. to Spus one

Hi,
    I am a newbie to R, just trying to switch from
Splus. I am wondering to know if there is any such
command in R as "attach" in Splus which can be used to
attach the full directory.

Also, any idea/referrence about, how to load c
functions in R would be highly appreciated.

Thanks,
Utsav