while(<DATA>) {
        my @columns;
        while(/("(?:\\\\|\\"|.)*?")| # "quoted"
                (\S+)                 # unquoted
               /gx) {
            my $match;
            if(defined $1) {         # matched quoted
                $match = $1;
                $match =~ s/^"//;    # remove opening "
                $match =~ s/"$//;    # remove closing "
            } else {
                $match = $2;
            }
            $match =~ s#\\\\#\\#g;   # \\ -> \
            $match =~ s#\\"#"#g;     # \" -> "
            push(@columns, $match);  # store
        }

        print join('/', @columns), "\n";
    }

    __DATA__
    foo bar baz
    foo "bar \\ baz" "foo \"the bar\" baz"
    fü bär bäz