On Wed, 2021-08-11 at 20:36 -0400, Greg Wooledge wrote: > On Wed, Aug 11, 2021 at 08:00:12PM -0400, Franklin, Jason wrote: > > This doesn't work unless it was recently fixed. A variation does... > > > > bash-5.0$ echo $BASH_VERSION > > 5.0.17(1)-release > > bash-5.0$ GROUPS=FOO bash -c 'echo $GROUPS' > > 1000 > > bash-5.0$ GROUPS=FOO bash --posix -c 'echo $GROUPS' > > 1000 > > bash-5.0$ env GROUPS=FOO bash -c 'echo $GROUPS' > > FOO > > bash-5.0$ env GROUPS=FOO bash --posix -c 'echo $GROUPS' > > FOO > > You can't overwrite GROUPS while you're inside of bash, apparently not > even in the temporary assignment context before a simple command. So, > in order for the first form to work as expected, you'd have to be in a > shell other than bash.
Exactly. I had thought that it was partially KRE's point. bash-5.0$ x=foo bash-5.0$ x=bar bash -c 'echo $x' bar bash-5.0$ echo $x foo The above is a reasonable expected behavior that works with "x" but fails with "GROUPS" and other such magic variables. The trick of "unset GROUPS" is the only way out. -- Jason Franklin
