Using sed to replace text with spaces with a defined variable with slashs

Question

I am trying to use sed to replace a line with spaces with a defined variable.

For example,

I want to replace 'a dumb string' with $lan, and lan="~/afile.py

I assumed the line would be

sed "s/a dumb string/$lan/g" file.txt

but this leave the 'a dumb string' part blank in the file.txt.

My problem seems simple enough. Any help is much appreciated.

Are you sure that you've set the variable `Ian`? What happens when you run `echo "<<$Ian>>"`? — ruakh, Mar 05 '13 at 23:40
@ruakh the $lan is set correctly, but I found the root of the problem. $lan is a file name and has slashes in it. I'll clarify the question. — NPB, Mar 05 '13 at 23:52

score 20 · Accepted Answer · edited May 19 '15 at 11:45

20

I determined that because my @lan variable has slashes in it, I need to use the sed command using :

For example

sed "s:a dumb string:$lan:g" file.txt

This is probably a novice mistake, but I'm not that familiar with sed. Thank you for your help.

edited May 19 '15 at 11:45

Uri Agassi

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answered Mar 05 '13 at 23:59

NPB

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score 18 · Answer 2 · answered Mar 06 '13 at 00:00

sed is not aware that you're passing a variable -- it'll be interpreted as just another part of your regex. If your substitution contains slashes, the easiest thing to do is use an alternate separator char, like this:

sed "s|a dumb string|$lan|g" file.txt

Vidya Patil · Answer 3 · 2016-11-07T06:42:00.403

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Sometime space in search string does not work so needed to use [[:space:]] in centos.

    sed -i 's/User[[:space:]]daemon/User apache/' httpd1.conf

edited Nov 07 '16 at 06:42

answered May 13 '16 at 16:54

Vidya Patil

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Using sed to replace text with spaces with a defined variable with slashs

3 Answers3

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