Add LANG=C to get tr working.

[DrearyLisper]

Without explicitly passing LANG=C it won't work correctly on Mac OS.

➜  ~ tr -dc "[:lower:]" < /dev/urandom | fold -w8 | head -n1
tr: Illegal byte sequence
➜  ~ LANG=C tr -dc "[:lower:]" < /dev/urandom | fold -w8 | head -n1
xwbersvj

[drduh]

Is this on macOS or were you seeing this on other platforms also? I have LC_ALL set in zshrc and haven't come across this error.

[DrearyLisper]

Yes, that was on MacOS.