Using sed and evironmental variables

[Bob Tanner <tanner@real-time.com>]

Is there a way to pass environmental variables into a sed script?

I have a env var called FOO=bob and the following sed script:

cat file | sed -e 's/FOO/$FOO/g'

I want to replace all occurances of "FOO" in file "file" with the value of the
environmental variable FOO, which has a value of bob.

Using the above sed script, all occurances of "FOO" are replaced by "$FOO",
not the bob (the value of $FOO).

Anyone?
-- 
Bob Tanner <tanner@real-time.com>       | Phone : (612)943-8700
http://www.real-time.com                | Fax   : (612)943-8500
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