How to use variables in a command in sed?

Question

I have abc.sh:

exec $ROOT/Subsystem/xyz.sh

On a Unix box, if I print echo $HOME then I get /HOME/COM/FILE.

I want to replace $ROOT with $HOME using sed.

Expected Output:

exec /HOME/COM/FILE/Subsystem/xyz.sh

I tried, but I'm not getting the expected output:

sed  's/$ROOT/"${HOME}"/g' abc.sh > abc.sh.1

Addition:

If I have abc.sh

exec $ROOT/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh

then with

sed "s|\$INSTALLROOT/|${INSTALLROOT}|" abc.sh

it is only replacing first $ROOT, i.e., output is coming as

exec /HOME/COM/FILE/Subsystem/xyz.sh $ROOT/ystem/xyz1.sh

possible duplicate of [replace a string in shell script](http://stackoverflow.com/questions/3306007/replace-a-string-in-shell-script) — tripleee, Oct 03 '13 at 06:54
@tripleee While I'm certain that this would be a duplicate of numerous other questions, the one that you've pointed to isn't the best one since it doesn't contain slashes in the variable. All answers therein use `/` as the separator. Obvious stuff, I know but leaves room for a better (duplicate) question. — devnull, Oct 03 '13 at 11:07

score 139 · Accepted Answer · edited Jan 11 '21 at 11:40

139

Say:

sed "s|\$ROOT|${HOME}|" abc.sh

Note:

EDIT: In order to replace all occurrences of $ROOT, say

sed "s|\$ROOT|${HOME}|g" abc.sh

edited Jan 11 '21 at 11:40

oguz ismail

answered Oct 03 '13 at 06:14

devnull

1

This completely did the trick. In case it helps anyone out, I did something like this: sed "s|@@ALF_INSTALL_DIR|${ALF_INSTALL_DIR}|g" files/tomcat/alfresco-global.properties.template > files/tomcat/alfresco-global.properties The variable contains "/" because it has a path to it (fwiw). – Harlin May 16 '20 at 15:21

potong · Answer 2 · 2013-10-03T08:15:36.327

26

This might work for you:

sed 's|$ROOT|'"${HOME}"'|g' abc.sh > abc.sh.1

edited Oct 03 '13 at 08:15

answered Oct 03 '13 at 06:33

potong

thanks, I had to add | sed 's/[{}]//g' to remove the brackets, but otherwise it worked – thistleknot Nov 24 '21 at 17:12

score 1 · Answer 3 · answered May 07 '20 at 10:31

1

This may also can help

input="inputtext"
output="outputtext"
sed "s/$input/${output}/" inputfile > outputfile

answered May 07 '20 at 10:31

pratibha

This could be problematic if input or output contains a slash – kvantour May 07 '20 at 12:02
I would want to have date variable and it looks like currentDate=$date sed -i '12s|$.*$|
My Report
Executed by: My Build tool
Executed on: $currentDate\1|' <> As we see, currentDate is being used in `sed -i` command. Is it possible to make it work ?
– user9920500 Jun 09 '20 at 17:24

Mihail H. · Answer 4 · 2021-12-24T20:54:44.623

0

The safe for a special chars workaround from https://www.baeldung.com/linux/sed-substitution-variables with improvement for \ char:

#!/bin/bash
to="/foo\\bar#baz"
echo "str %FROM% str" | sed "s#%FROM%#$(echo ${to//\\/\\\\} | sed 's/#/\\#/g')#g"

edited Dec 24 '21 at 20:54

answered Dec 24 '21 at 20:18

Mihail H.

4 Answers4