Re:How does apt render its fancy progress bar?
by junon on Wednesday October 13, 2021 @12:50PM
(#28854505)
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).
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).
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).