Bash printing color codes literally and not in actual color

Question

For some reason my shell script stopped printing my menu in color and is actually printing the literal color code instead. Did I somehow escape the color coding?

Script

#!/bin/bash 

function showEnvironments {
echo -e "\e[38;5;81m"
echo -e "      SELECT ENVIRONMENT       "
echo -e "[1] - QA"
echo -e "[2] - PROD"
echo -e "\e[0m"
}

showEnvironments

Output

\e[38;5;81m

SELECT ENVIRONMENT

[1] - Staging

[2] - QA

\e[0m

I am using iTerm on Mac OSX and the TERM environment variable is set to xterm-256color.

You should edit your question to include the terminal emulator that you're using and the contents of the `TERM` environment variable. — Anthony Geoghegan, May 09 '16 at 12:38
TERM=xterm-256color TERM_PROGRAM=iTerm.app Is that what you were looking for? — Adrian E, May 09 '16 at 12:50
Yes. I've edited your question to include this important information. I don't use a Mac so I don't know how iTerm would need to be configured to interpret ANSI escape sequences correctly. — Anthony Geoghegan, May 09 '16 at 13:05
See [*Makefile* Adding colors doesn't work on OS X](http://stackoverflow.com/questions/36021056/makefileadding-colors-doesnt-work-on-os-x/36021490) — Thomas Dickey, May 11 '16 at 23:38
fwiw I ended up just outputting to a file: `echo "$stuff" >> myscript.sh` — Devin Rhode, Oct 10 '21 at 17:33
(I had opposite problem, needing to inspect raw text, without interpretation) — Devin Rhode, Oct 10 '21 at 17:39

score 19 · Accepted Answer · answered May 09 '16 at 14:57

19

There are several apparent bugs in the implementation of echo -e in bash 3.2.x, which is what ships with Mac OS X. The documentation claims that \E (not \e) represents ESC, but neither appears to work. You can use printf instead:

printf "\e[38;5;81mfoo\e[0m\n"

or use (as you discovered) \033 to represent ESC.

Later versions of bash (definitely 4.3, possible earlier 4.x releases as well) fix this and allow either \e or \E to be used.

answered May 09 '16 at 14:57

chepner

497,756
71
530
681

I wonder how this is handled with zsh? – Devin Rhode Oct 10 '21 at 17:34
1

Works fine in `zsh`, at least in 5.7.1. I don't know if there was ever a similar bug in older versions of `zsh` (I see no reason to think there would be just because `bash` had one.) – chepner Oct 11 '21 at 12:50
It's less of an issue in `zsh` (unless you are trying to use it as a POSIX shell, for example as `/bin/sh`), because you can write things like `print -P "%F{81}foo%f"` in a terminal-independent way. – chepner Oct 11 '21 at 12:52

score 10 · Answer 2 · answered May 09 '16 at 12:30

Two ways to do this: reference colors directly or assign to variable to reference them easier later in the script.

cNone='\033[00m'
cRed='\033[01;31m'
cGreen='\033[01;32m'
cYellow='\033[01;33m'
cPurple='\033[01;35m'
cCyan='\033[01;36m'
cWhite='\033[01;37m'
cBold='\033[1m'
cUnderline='\033[4m'

echo -e "\033[01;31m"
echo -e "hello"
echo -e "\033[00m"

echo -e "${cGreen}"
echo -e "hello"
echo -e "${cNone}"

I hope this helps.

score 4 · Answer 3 · answered May 09 '16 at 13:21

I figured it out. It appears that the escape character I am using for the color code is not recognized in my terminal.

Based on http://misc.flogisoft.com/bash/tip_colors_and_formatting#colors1 valid escape codes are:

\e
\033
\x1B

When I changed my colors from \e[38;5;81m to \033[38;5;81m it started working as expected.

Thanks to everyone else for the suggestions and help!

score 1 · Answer 4 · answered May 09 '16 at 12:03

1

Two potential things to try:

run stty sane to reset the terminal settings
check the $TERM environment variable

answered May 09 '16 at 12:03

ankon

4,128
2
26
26

Bash printing color codes literally and not in actual color

4 Answers4

Linked