When I tried either of these, on my macOS, I got tr: Illegal byte sequence which I got around by changing the locale: ( export LC_ALL=C; tr -dc '0-9' < /dev/

When I tried either of these, on my macOS, I got tr: Illegal byte sequence which I got around by changing the locale: ( export LC_ALL=C; tr -dc '0-9' < /dev/urandom | head -c 7 ) with help from: https://unix.stackexchange.com/questions/141420/tr-complains-of-illegal-byte-sequence https://unix.stackexchange.com/questions/141420/tr-complains...