Bash sed doesn't include dots in strings given through variables

Question

Hello there I have run into that problem:

The following code does not replace line that contains $variable1 with the content of $variable2:

variable1=$(cat pathtofile1 | grep -w "something.more")
variable2=$(cat pathtofile2 | grep -w "something.else")

sed -i 's/$variable1/$variable2/g' pathtofile1

I want to copy the entire line from one file to another but it doesn't work, I think it has to do something with the dots in the variable's content but I don't seem to get it fixed no matter what.

Can someone help?

Thanks in advance.

EDIT: Edited the question because it was not clear enough what I wanted to do. I want to replace the line in file1 that contains the quoted text with the line of file2 that contains the second quoted text.

It has nothing to do with dots. You're setting variables in the shell but trying to use them in sed. Sed has no variables. (And that's not how you set variables in bash.) — melpomene, Apr 27 '17 at 20:56
I tried it, still it doesn't replace them. 'sed -i "s/\"${variable1}\"/\"${lvariable2}\"/g" pathtofile1' — 3rr0r 404, Apr 27 '17 at 21:24
Try `sed "s/$var1/$var2/"` – no escaped double quotes inside. — Benjamin W., Apr 27 '17 at 21:34
Wait, are you trying to replace the *line* that contains `something.more` with the line that contains `something.else`? — Benjamin W., Apr 27 '17 at 22:03

yoones · Answer 1 · 2017-04-27T21:25:44.190

1

First you need to use doublequotes instead of simple quotes for your variables to be interpreted as such. Then you need to escape the dots in your variables to be interpreted as dot characters and not regex interpretation that says any character.

Also you're not setting you variables right.

yoones@laptop:/tmp/toto$ cat f1
toto #aabbcc
titi #fff000
tata #212322
yoones@laptop:/tmp/toto$ cat f2
hello #ababab
good #123456
morning #fafafa
yoones@laptop:/tmp/toto$ cat x.sh 
#!/bin/bash

variable1=$(cat f1 | fgrep '#fff00' | sed -e 's/[]\/$*.^|[]/\\&/g')
variable2=$(cat f2 | fgrep '#fafafa' | sed -e 's/[]\/$*.^|[]/\\&/g')

sed -i "s/$variable1/$variable2/g" f1
yoones@laptop:/tmp/toto$ ./x.sh 
yoones@laptop:/tmp/toto$ cat f1
toto #aabbcc
morning #fafafa
tata #212322
yoones@laptop:/tmp/toto$ cat f2
hello #ababab
good #123456
morning #fafafa
yoones@laptop:/tmp/toto$

edited Apr 27 '17 at 21:25

answered Apr 27 '17 at 20:55

yoones

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I updated the question because it was not clear enough what I wanted to do. I hope you can understand it now. – 3rr0r 404 Apr 27 '17 at 21:05
My code work for your use case, be you have to use double quotes `"`, not simple quotes `'` – yoones Apr 27 '17 at 21:11
I just tested it but it doesn't work. Please check the edit on the question because I have copied the exact way that I want to do this process. – 3rr0r 404 Apr 27 '17 at 21:13
Can you provide a sample of line to be replaced with its replacement? – yoones Apr 27 '17 at 21:14
I want lines like: 'something.more : #fff000' To be replaced with another hex code contained in the second folder: 'something.more: #fafafa' – 3rr0r 404 Apr 27 '17 at 21:16
I tried your updated unswer and still it ignores lines that have the dot in the middle of the string. – 3rr0r 404 Apr 27 '17 at 21:20
@3rr0r404 Here you go. – yoones Apr 27 '17 at 21:26
I tested your example but unfortunately it doesn't work if I have a dot in the fgrep string. – 3rr0r 404 Apr 27 '17 at 21:32
fgrep doesn't mind having dots in the string. I can't help you more without full files and keywords – yoones Apr 27 '17 at 21:34
Is there any way so that I can contact you? – 3rr0r 404 Apr 27 '17 at 21:45

Bash sed doesn't include dots in strings given through variables

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