sed replace exact match

Question

I want to change some names in a file using sed. This is how the file looks like:

#! /bin/bash

SAMPLE="sample_name"
FULLSAMPLE="full_sample_name"

...

Now I only want to change sample_name & not full_sample_name using sed

I tried this

sed s/\<sample_name\>/sample_01/g ...

I thought \<> could be used to find an exact match, but when I use this, nothing is changed.

Adding '' helped to only change the sample_name. However there is another problem now: my situation was a bit more complicated than explained above since my sed command is embedded in a loop:

while read SAMPLE
do
    name=$SAMPLE
    sed -e 's/\<sample_name\>/$SAMPLE/g' /path/coverage.sh > path/new_coverage.sh
done < $1

So sample_name should be changed with the value attached to $SAMPLE. However when running the command sample_name is changed to $SAMPLE and not to the value attached to $SAMPLE.

Answer 1

I believe \< and \> work with gnu sed, you just need to quote the sed command:

sed -i.bak 's/\<sample_name\>/sample_01/g' file