Ask sed to ignore all special characters

Question

I use the following code to delete a line :

sed -i "0,/$DELETE_THIS/{/$DELETE_THIS/d;}" file.txt

But this code fails if the variable DELETE_THIS contains special characters, like ., /, * and so on...

Is there a way to tell sed to ignore all special characters and use them as basic text ?

You would have to escape any special characters in your query expression. Related: What characters do I need to escape when using sed in a sh script? — Kusalananda, Dec 05 '18 at 11:49

score 6 · Accepted Answer · answered Dec 05 '18 at 11:51

You have a string in $DELETE_THIS, which you want to pass to sed in such a way that sed will treat it literally.
For this, you must quote all characters which are meaningful to sed.

Put a backslash before them. For example, using Bash syntax:

DELETE_THIS="$(<<< "$DELETE_THIS" sed -e 's`[][\\/.*^$]`\\&`g')"

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