[R] system shell emulation in R

[Shin, Daehyok]

Rather than using system() to execute a shell command,
is there a way to emulate the system shell itself in R?
For instance, if the function is shell, 

> getwd()
[1] "/home/a/b"
> shell()          # From R to system shell
$cd ..              # cd command in system shell
$CTRL+D	       # Return to R
> getwd()
[1] "/home/a"

Thanks in advance.

Daehyok Shin (Peter)
Terrestrial Hydrological Ecosystem Modellers
Geography Department
University of North Carolina-Chapel Hill
sdhyok at email.unc.edu

"We can do no great things, 
only small things with great love."
                         - Mother Teresa