CODEWITHSUNDEEP
bashsh
Chris Tran
Chris Tran

Reputation: 13

Using sed to add multiple lines of variables in beginning of file

I'm trying to write 3 lines at the beginning of my file using sed. I've decided to assign these to variables because they're pretty long texts and it would be easier to read.

I'm trying to add:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE wo-national-phase-information SYSTEM "wo-national-phase-information-v1-5.dtd">
<wo-national-phase-information country='US' file-name='US-IB-FEB-2019.xml'>

I've assigned each one to: SED_HELPER_ONE SED_HELPER_TWO SED_HELPER_THREE

respectively. Also, is it possible to use variables in the sed command?

Upvotes: 0

Views: 82

Answers (2)

glenn jackman
glenn jackman

Reputation: 247210

If you insist on sed:

v1='<?xml version="1.0" encoding="UTF-8"?>'
v2='<!DOCTYPE wo-national-phase-information SYSTEM "wo-national-phase-information-v1-5.dtd">'
v3="<wo-national-phase-information country='US' file-name='US-IB-FEB-2019.xml'>"

sed "1i\\
$v1\\
$v2\\
$v3" file

If it works as you want, add the -i option to save in-place.

Upvotes: 2

chepner
chepner

Reputation: 532418

I wouldn't even use sed for this. Instead, use cat

cat - foo.xml > tmp <<EOF && mv tmp foo.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE wo-national-phase-information SYSTEM "wo-national-phase-information-v1-5.dtd">
<wo-national-phase-information country='US' file-name='US-IB-FEB-2019.xml'>
EOF

Upvotes: 2

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