how to escape file path in bash script variable

Question

I would like to escape a file path that is stored in a variable in a bash script. I read several threads about escaping back ticks or but it seems not working as it should:

I have this variable: The variables value is entered during the bash script execution as user parameter

CONFIG="/home/teams/blabla/blabla.yaml"

I would need to change this to: \/home\/teams\/blabla\/blabla.yaml

How can I do that with in the script via sed or so (not manually)?

I'm not quite sure what the question is but you can do something like that I believe: ```\/home\/teams\/blabla\/blabla.yaml```, escaping the / sign — Bogdan Stoica, Oct 13 '21 at 13:04

score 2 · Accepted Answer · answered Oct 13 '21 at 13:43

2

With GNU bash and its Parameter Expansion:

echo "${CONFIG//\//\\/}"

Output:

\/home\/teams\/blabla\/blabla.yaml

answered Oct 13 '21 at 13:43

Cyrus

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score 1 · Answer 2 · answered Oct 13 '21 at 13:43

1

Using the solution from this question, in your case it will look like this:

CONFIG=$(echo "/home/teams/blabla/blabla.yaml" | sed -e 's/[]\/$*.^[]/\\&/g')

answered Oct 13 '21 at 13:43

Taras Khalymon

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score 0 · Answer 3 · answered Oct 13 '21 at 13:32

echo "/home/teams/blabla/blabla.yaml" | sed 's/\//\\\//g'
\/home\/teams\/blabla\/blabla.yaml

explanation:

backslash is used to set the following letter/symbol as an regular expression or vice versa. double backslash is used when you need a backslash as letter.

score 0 · Answer 4 · answered Oct 13 '21 at 13:55

Why does that need escaping? Is this an XY Problem?

If the issue is that you are trying to use that variable in a substitution regex, then the examples given should work, but you might benefit by removing some of the "leaning toothpick syndrom", which many tools can do just by using a different match delimiter. sed, for example:

$: sed "s,SOME_PLACEHOLDER_VALUE,$CONFIG," <<< SOME_PLACEHOLDER_VALUE
/home/teams/blabla/blabla.yaml

Be very careful about this, though. Commas are perfectly valid characters in a filename, as are almost anything but NULLs. Know your data.

how to escape file path in bash script variable

4 Answers4