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Comment by rbonvall | Hacker News Reader

Standardness notwithstanding, using tput is more readable and memorable. I can type this from memory:

    echo "I'm $(tput setaf 4)blue$(tput sgr0)."

but I couldn't get this one right without looking it up:

    echo -e "I'm \033[0;34mblue\033[0m."

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Because you're using a lot more characters than you need.

    echo -e "I'm \e[34mblue\e[m."

However, `tput` is definitely the more 'correct' approach. What actual benefit it affords you over the hardcoded escapes is left to edge-cases and very, very old or otherwise niche terminal emulators.

By the way, the `3x` means foreground, the `4x` means background. `x` is a number between 0 and 7 (inclusive) that indicates the color. `x=8` means "extended"/non-standard and generally takes a few more control codes afterward, and `x=9` means "reset".

If you know binary, you can remember the 0-7 colors. It's a 3-bit code corresponding to BGR (where B is the MSB).

    BGR
    000 = 0 = black
    001 = 1 = red
    010 = 2 = green
    011 = 3 = yellow
    100 = 4 = blue
    101 = 5 = magenta
    110 = 6 = cyan
    111 = 7 = white

You can also add 60 to the code to make it "bright", e.g. red foreground (31) can be made bright red by adding 31+60=91. Same can be applied to backgrounds (4x+60=10x).

The bright codes are less supported though admittedly I've never seen a modern emulator that doesn't. It also gives you bright colors on old Windows cmd.exe prompts without needing the bold mode (1).

Still not particularly readable or memorable. You still need to remember that blue is color number 4 and that "sgr0" is "exit_attribute_mode", what you might call "reset".

Store the sequences in variables and put those instead. You get readability and locality!

I was about to post the exact same reply so I will post it as an example:

  #!/bin/sh
  BLUE=$(tput setaf 4)
  RST=$(tput sgr0)
  echo "I'm ${BLUE}blue${RST}."

  alias red='echo -ne "\e[31m"'
  alias yellow='echo -ne "\e[33m"'
  alias green='echo -ne "\e[32m"'
  alias blue='echo -ne "\e[34m"'
  alias cyan='echo -ne "\e[36m"'
  alias violet='echo -ne "\e[35m"'
  alias grey='echo -ne "\e[90m"'
  alias gray='echo -ne "\e[90m"'
  alias white='echo -ne "\e[37m"'
  alias bold='echo -ne "\e[1m"'
  alias flash='echo -ne "\e[7m\e[5m"'
  alias normal='echo -ne "\e(B\e[m"'

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