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About sed : How-to-escape-single-quote-in-sed

Question Detail

How to escape a single quote in a sed expression that is already surrounded by quotes?

For example:

sed ‘s/ones/one’s/’ <<< 'ones thing'

Question Answer

Quote sed codes with double quotes:

$ sed “s/ones/one’s/”<<<"ones thing" one's thing I don't like escaping codes with hundreds of backslashes – hurts my eyes. Usually I do in this way: $ sed 's/ones/one\x27s/'<<<"ones thing" one's thing ............................................................ One trick is to use shell string concatenation of adjacent strings and escape the embedded quote using shell escaping: sed 's/ones/two'\''s/' <<< 'ones thing' two's thing There are 3 strings in the sed expression, which the shell then stitches together: sed 's/ones/two' \' 's/' Hope that helps someone else! ............................................................ The best way is to use $'some string with \' quotes \'' eg: sed $'s/ones/two\'s/' <<< 'ones thing' ............................................................ Just use double quotes on the outside of the sed command. $ sed "s/ones/one's/" <<< 'ones thing' one's thing It works with files too. $ echo 'ones thing' > testfile
$ sed -i “s/ones/one’s/” testfile
$ cat testfile
one’s thing

If you have single and double quotes inside the string, that’s ok too. Just escape the double quotes.

For example, this file contains a string with both single and double quotes. I’ll use sed to add a single quote and remove some double quotes.

$ cat testfile
“it’s more than ones thing”
$ sed -i “s/\”it’s more than ones thing\”/it’s more than one’s thing/” testfile
$ cat testfile
it’s more than one’s thing

……………………………………………………
Escaping single quote in sed: 3 different ways:
From fragile to solid…
1. Using double-quotes to enclose sed script:
Simpliest way:
sed “s/ones/one’s/” <<< 'ones thing' But using double-quote lead to shell variables expansion and backslashes to be considered as shell escape before running sed. 1.1. Specific case without space and special chars In this specific case, you could avoid enclosing at shell level (command line): sed s/ones/one\'s/ <<<'ones thing' will work until whole sedscript don't contain spaces, semicolons, special characters and so on... (fragile!) 2. Using octal or hexadecimal representation: This way is simple and efficient, if not as readable as next one. sed 's/ones/one\o047s/' <<< 'ones thing' sed 's/ones/one\x27s/' <<< 'ones thing' And as following character (s) is not a digit, you coul write octal with only 2 digits: sed 's/ones/one\o47s/' <<< 'ones thing' 3. Creating a dedicated sed script First ensure correct path to sed tool: which sed /bin/sed Then adapt shebang in following: cat <<"eosedscript" >sampleSedWithQuotes.sed
#!/bin/sed -f

s/ones/one’s/;
eosedscript
chmod +x sampleSedWithQuotes.sed

From there, you could run:
./sampleSedWithQuotes.sed <<<'ones thing' one's thing This is the strongest and simpliest solution as your script is the most readable:$ cat sampleSedWithQuotes.sed #!/bin/sed -f s/ones/one's/; 3.1 You coud use -i sed flag: As this script use sed in shebang, you could use sed flags on command line. For editing file.txt in place, with the -i flag: echo >file.txt ‘ones thing’
./sampleSedWithQuotes.sed -i file.txt
cat file.txt
one’s thing

……………………………………………………
This is kind of absurd but I couldn’t get \’ in sed ‘s/ones/one\’s/’ to work. I was looking this up to make a shell script that will automatically add import ‘hammerjs’; to my src/main.ts file with Angular.

What I did get to work is this:

apost=\’
sed -i ” ‘/environments/a\
import ‘$apost’hammerjs’$apost’;’ src/main.ts

So for the example above, it would be:

apost=\’
sed ‘s/ones/one’$apost’s/’

I have no idea why \’ wouldn’t work by itself, but there it is.
……………………………………………………
Some escapes on AppleMacOSX terminals fail so:

sed ‘s|ones|one’$(echo -e “\x27”)’s|1’ <<<'ones thing' ............................................................ I know this is going to sound like a cop out but I could never get sed working when there were both single and double quotes in the string. To help any newbies like me that are having trouble, one option is to split up the string. I had to replace code in over 100 index.hmtl files. The strings had both single and double quotes so I just split up the string and replaced the first block with . It made a mess of my index.html files but it worked.
……………………………………………………
use an alternative string seperator like “:” to avoid confusion with different slashes

sed “s:ones:one’s:” <<< 'ones thing' or if you wish to highligh the single quote sed "s:ones:one\'s:" <<< 'ones thing' both return one's thing

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