escaping double quotes inside backticks?

[John Brock]

I'm trying to construct a command containing double quotes, e.g.: scp "StrictHostKeyChecking no" source us...@127.0.0.1:~

However, I can't figure out how to escape the double quotes when using the julia backtick syntax. For example, none of the following work:

julia> `scp "StrictHostKeyChecking no" source us...@127.0.0.1:~`
`scp 'StrictHostKeyChecking no' source us...@127.0.0.1:~`


julia> `scp \"StrictHostKeyChecking no\" source us...@127.0.0.1:~`
`scp '"StrictHostKeyChecking' 'no"' source us...@127.0.0.1:~`


julia> `scp """StrictHostKeyChecking no""" source us...@127.0.0.1:~`
`scp 'StrictHostKeyChecking no' source us...@127.0.0.1:~`

Any suggestions?

[Steven G. Johnson]

On Thursday, October 8, 2015 at 7:16:34 PM UTC-4, John Brock wrote:

I'm trying to construct a command containing double quotes, e.g.: scp "StrictHostKeyChecking no" source us...@127.0.0.1:~

However, I can't figure out how to escape the double quotes when using the julia backtick syntax. For example, none of the following work:

julia> `scp "StrictHostKeyChecking no" source us...@127.0.0.1:~`
`scp 'StrictHostKeyChecking no' source us...@127.0.0.1:~`

First, are you sure you actually want to pass double quotes to `scp`?  Double quotes are used in the shell to prevent spaces from being parsed as separate arguments, they aren't actually passed to `scp`.   The above example is correct if you want to pass 

     StrictHostKeyChecking no

as the first argument of scp, and is equivalent to 

     scp "StrictHostKeyChecking no" source us...@127.0.0.1:~

in a shell like bash.

If you actually wanted to pass double quotes to `scp` as part of the arguments, you would escape them exactly a you would declare a literal string with quotes in Julia:

     julia> `scp "\"StrictHostKeyChecking no\"" source us...@127.0.0.1:~`

     `scp '"StrictHostKeyChecking no"' source us...@127.0.0.1:~`

--SGJ

      

[John Brock]

A-ha, I see, thanks. Also, for anyone who comes across this post, I forgot the -o flag before 'StrictHostKeyChecking no'.