sed insert line with leading spaces

bradvan · 03-03-2011, 08:02 AM

Hi,

I'm trying to insert a line using sed that has leading spaces before the text. Sed seems to be just dropping the spaces and only inserting the text. Any ideas what I'm missing?

Code:

NAM=rb134
sed -i.bak -e "\$i \
        host ${NAM} {" /etc/crap

Instead of inserting a line with 8 leading spaces inserts it with "host" at the beginning of the line. I tried

Code:

NAM=rb134
sed -i.bak -e "\$i \
^        host ${NAM} {" /etc/crap

but it put the "^" at the begging of the line.

Thanks!

bradvan · 03-03-2011, 08:08 AM

I found a solution. Not sure if it is the best, but it works.

Code:

NAM=rb134
sed -i.bak -e "\$i \
\ \ \ \ \ \ \ \ host ${NAM} {" /etc/crap

colucix · 03-03-2011, 08:11 AM

Not actually the best, but it works indeed. To force sed to not ignore the leading spaces you can simply put a backslash at the beginning of the line:

Code:

NAM=rb134
sed -i.bak -e "\$i \
\        host ${NAM} {" /etc/crap

It is documented here: http://www.grymoire.com/Unix/Sed.html#uh-43.

carltm · 03-03-2011, 08:14 AM

Try this. It should just be another way to do the same thing.
If it works, I don't know why your version didn't work.

Code:

NAM=rb134
sed -i.bak '$i\
        host '"$NAM"' {' /etc/crap

bradvan · 03-03-2011, 08:45 AM

Thanks! I'll give it a try.

bradvan · 03-04-2011, 04:40 AM

Both worked great. Thanks!!!

colucix · 03-04-2011, 04:51 AM

You're welcome!