Bash - export environment variables with special characters ($)

Question

I'm parsing a file with key=value data and then export them as environment variables. My solution works, but not with special characters, example:

.data

VAR1=abc
VAR2=d#r3_P{os-!kblg1$we3d4xhshq7=mf$@6@3l^

script.sh

#!/bin/bash
while IFS="=" read -r key value; do
  case "$key" in
    '#'*) ;;
    *)
      eval "$key=\"$value\""
      export $key
  esac
done < .data

$ . ./script.sh

Output:

$ echo $VAR1
abc
$ echo $VAR2
d#r3_P{os-!kblg1=mf6@3l^

but should be: d#r3_P{os-!kblg1$we3d4xhshq7=mf$@6@3l^

Try single quotes? That seemed to work for me. – Ben Creasy Sep 30 '18 at 08:51 — Ben Creasy, Sep 30 '18 at 08:51

score 47 · Answer 1 · answered Aug 02 '21 at 02:09

47

Just use single quotes:

export VAR2='d#r3_P{os-!kblg1$we3d4xhshq7=mf$@6@3l^'

answered Aug 02 '21 at 02:09

Bernardo Ramos

4,048
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2

if string contain , then VAR2 will become array and whole string will be split with , – ImranRazaKhan Jan 24 '22 at 17:13

score 17 · Answer 2 · answered Apr 19 '17 at 12:33

17

Just escape the $ sign with backslash \

answered Apr 19 '17 at 12:33

Yedidia

969
7
12

3

If the data is automatically generated by some 3rd-party application and saved in the `.data` file then you might not be able to do it in an automated environment – Rogus Apr 19 '17 at 12:37
1

how do you escape `&` ? – nurettin May 05 '19 at 10:54
1

also with a backslash, here is an exmaple: `# echo \&` `&` – Yedidia May 06 '19 at 12:38
1

Very inefficient if you have multiple characters that will need to be passed escaped – Mitch Aug 31 '19 at 18:15
you escape ^ in the same manner. I do not have the list of special characters that can be escaped with \ but one can empirically conjecture and verify at the command line – David Nov 02 '21 at 19:01

score 3 · Accepted Answer · answered Apr 19 '17 at 12:39

3

You don't need eval at all, just use declare built-in in bash to create variables on-the-fly!

case "$key" in
  '#'*) ;;
   *)
       declare $key=$value
       export "$key"
esac

answered Apr 19 '17 at 12:39

Inian

80,270
14
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161

score 3 · Answer 4 · answered Feb 19 '21 at 14:08

3

I found the following script (to be sourced) helpful:

set -a
source <(cat development.env | \
    sed -e '/^#/d;/^\s*$/d' -e "s/'/'\\\''/g" -e "s/=\(.*\)/='\1'/g")
set +a

From: https://stackoverflow.com/a/66118031/339144

answered Feb 19 '21 at 14:08

Klaas van Schelven

2,374
1
21
35

score 2 · Answer 5 · answered Apr 19 '17 at 12:33

If you cannot change the .data file you have to escape the special character $ when assigning the value to key. Change the assignment line to:

eval "$key=\"${value//\$/\\\$}\""

${variable//A/B} means substituting every instance of A to B in variable.

More useful info on bash variables here

Bash - export environment variables with special characters ($)

5 Answers5