I am trying to rename all files in a folder replacing underscores with spaces.

i.e. this_is_a_test --> this is a test

but somehow I'm messing up the quoting

> for file in * ; do echo mv -v $file $(echo $file | sed 's/_/ /g') ; done

mv -v this_is_a_test this is a test

that looks OK, but if I remove the 'echo' mv complains as if the backslashes were removed

> for file in * ; do mv -v $file $(echo $file | sed 's/_/ /g') ; done

mv: target ‘test’ is not a directory

Can someone point out the error of my ways?