How to replace a whole line with sed?

Question

Suppose I have a file with lines

aaa=bbb

Now I would like to replace them with:

aaa=xxx

I can do that as follows:

sed \"s         


        

Answer 1

This might work for you:

cat <<! | sed '/aaa=\(bbb\|ccc\|ffffd\)/!s/\(aaa=\).*/\1xxx/'
> aaa=bbb
> aaa=ccc
> aaa=ffffd
> aaa=[something else]
!
aaa=bbb
aaa=ccc
aaa=ffffd
aaa=xxx

Answer 2

If you would like to use awk then this would work too

awk -F= '{$2="xxx";print}' OFS="\=" filename

Answer 3

Try this:

sed "s/aaa=.*/aaa=xxx/g"

Answer 4

You can also use sed's change line to accomplish this:

sed -i "/aaa=/c\aaa=xxx" your_file_here

This will go through and find any lines that pass the aaa= test, which means that the line contains the letters aaa=. Then it replaces the entire line with aaa=xxx. You can add a ^ at the beginning of the test to make sure you only get the lines that start with aaa= but that's up to you.

Answer 5

sed -i.bak 's/\(aaa=\).*/\1"xxx"/g' your_file

Answer 6

Like this:

sed 's/aaa=.*/aaa=xxx/'

If you want to guarantee that the aaa= is at the start of the line, make it:

sed 's/^aaa=.*/aaa=xxx/'