variables set on command line

[Sam Steingold]

CYGWIN_NT-5.2-WOW64 sds 1.7.9(0.237/5/3) 2011-03-29 10:10 i686 Cygwin
BASH_VERSION='4.1.10(4)-release'

at the bash prompt I observe this:
$ f(){ echo a=$a b=$b c=$c ; }
$ unset a b c
$ a=a b=b f
a=a b=b c=
$ f
a= b= c=
which I believe is correct (i.e., variables set in "a=a b=b f" are unset
after f terminates).

alas, when I call /bin/sh on the same machine, I see this:

f(){ echo a=$a b=$b c=$c ; }
f
a= b= c=
a=a b=b f
a=a b=b c=
f
a=a b=b c=
exit

i.e., variables set in "a=a b=b f" survive to the next command.
$ /bin/sh --version
GNU bash, version 4.1.10(4)-release (i686-pc-cygwin)

is this the expected behavior?

thanks.

-- 
Sam Steingold (http://sds.podval.org/) on CentOS release 5.6 (Final) X 
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