Bash Script单引号内的双引号

Question

Yeah, this is kind of messed up but I have to do something like the following (this is just a simplified example):

sudo -H -u user1 bash -c 'ssh -I /home/user1/.ssh/id_rsa -f user2@machine1.domain1.com “find ./ -name '*.txt'”'

I have a need to have single quotes which are inside of double quotes which are inside of single quotes. Doesn't seem the standard '"'"' would work since the doubles would close the doubles rather than quoting a single. Would it maybe be: "'"'""' for each single I need inside there?

I've tried just skipping the ' around the ssh command but of course that failed.

Answer 1

You don't need the bash -c layer; just run ssh itself directly from sudo .

sudo -H -u user1 ssh -I /home/user1/.ssh/id_rsa -f user2@machine1.domain1.com "find ./ -name \"*.txt\""

(The -I option should be unnecessary; if ssh is run as user1 , then the default key is ~user1/.ssh/id_rsa . You may have meant -i anyway; -I specifies a PKCS#11 library to use, not a private key.)

That said, you cannot include single quotes inside a single-quoted string. When in doubt, use double quotes, and properly escape any nested double quotes.

Answer 2

chepner's answer is sufficient. If bash -c required, this solution which looks messy can be used:

sudo -H -u user1 bash -c 'ssh -I /home/user1/.ssh/id_rsa -f user2@machine1.domain1.com "find ./ -name '"'"'*.txt'"'"'"'

explanation

'... "find ./ -name '[first ' ended here]  "'" [second ' quote start]  '*.txt'[pattern]  "'"[second ' end] '"'[ " ended here]

I replaced ' with ' .