Can system modify an environment variable in the current environment?

[Mortimer Cladwell <mbcladwell@gmail.com>]

Hi,

Consider my file test.scm:

(define (main args)
  (let* ((myvar (string-append "export
GUILE_LOAD_PATH=/some/random/text:$GUILE_LOAD_PATH"))
           (statement1 (system (string-append "echo " myvar " >>
$HOME/.bashrc")))
            (statement2 (system myvar)))
    (write myvar)))

At the terminal:

mbc@HP8300:~/temp$ echo $GUILE_LOAD_PATH
/home/mbc/.guix-profile/share/guile/site/3.0

mbc@HP8300:~/temp$ guile -e main -s test.scm
"export GUILE_LOAD_PATH=/some/random/text:$GUILE_LOAD_PATH"

mbc@HP8300:~/temp$ echo $GUILE_LOAD_PATH
/home/mbc/.guix-profile/share/guile/site/3.0

At the end of .bashrc I see the last line is:

export
GUILE_LOAD_PATH=/some/random/text:/home/mbc/.guix-profile/share/guile/site/3.0

If I close and reopen the terminal and:

mbc@HP8300:~$ echo $GUILE_LOAD_PATH
/some/random/text:/home/mbc/.guix-profile/share/guile/site/3.0

So statement1 works as expected, modifying .bashrc which is then effective
in modifying GUILE_LOAD_PATH on future invocations of terminal.

statement2 is an attempt to modify the current running environment, but
fails.
Note that if I paste export
GUILE_LOAD_PATH=/some/random/text:$GUILE_LOAD_PATH directly into the
terminal, that successfully modifies the variable.

Why does  (system myvar) i.e. (system "export
GUILE_LOAD_PATH=/some/random/text:$GUILE_LOAD_PATH") fail?
Thanks
Mortimer