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Comment by juped | Hacker News Reader

What's even more nuts about Unix 300-layers-of-tty-emulation \n acting like a CRLF is that \r still works just fine as CR. e.g., you can get a nice little clock with:

  while true; do echo -n "  $(date)\r"; sleep 1; done

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I need to use printf to interpret the escape character:

    while true; do printf "  $(date)\r"; sleep 1; done

It might also work with "echo -e".

I like my terminals a little bit cleaner:

    printf '\033c';  while true; do echo -en "  $(date)\r"; sleep 1; done

(don't forget "-e" for echo)

  while true; do echo -en "  $(date)\r"; sleep 1; done

Depends on your echo. Zsh's interpretes escape sequences by default unless the "BSD_ECHO" option is used, bash's doesn't unless "xpg_echo" is on.

And xpg_echo is on by default for bash on macOS, so for users on macOS it looks like echo interprets escapes by default.

This is one of the reasons why echo is hopelessly unportable.

See https://unix.stackexchange.com/a/65819/55665

Learn something new every day!

And I wish we had a stronger word than unportable for echo. You see that word tossed around on shell scripting resources where the only system it applies to is a 30 year old version of ksh and it only blows up on a full moon when passed a filename with a literal form feed \f, but echo is a practical portability problem.

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