pipe affects scope of globals?

["Dwyer, William K" <bill.dwyer@xxxxxxxxxxxxxxxxxx>]

hi,

i have a possible bug. maybe i deserve it for using globals ;)  but i still
think this should not be the behaviour of scoping variables in the shell.
calling a function and piping it to read a variable seems to affect the
scope of its internal variables!  huh?  here is example code:

add_1_to_x_and_echo_2() {
        (( x = x + 1 ))
        echo 2
}

x=0
y=1
echo BEFORE
echo x=$x
echo y=$y

echo "call add_1_to_x_and_echo_2 and don't pipe to read"
add_1_to_x_and_echo_2

echo AFTER
echo x=$x
echo y=$y

echo "now call add_1_to_x_and_echo_2 and pipe to read"
add_1_to_x_and_echo_2 | read y

echo AFTER
echo x=$x
echo y=$y

echo "oooops! why didn't x change?"


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