Sorry. My issue is not about double quote or spaces, it's about spaces and single quote (or apostrophe). For example, I have commands which take a query as parameter. I used to write the query with doubles quotes, because there is a lot of spaces. However, I can't use an apostrophe in this kind of query.

If I use your example below, you can see it "looks" like using a quote worked because the syntax error disappears. however it's not, an invalid user has been created with a backslash.

karaf@root()> feature:repo-add mvn:org.apache.karaf.examples/karaf-command-example-features/4.2.9/xml
Adding feature url mvn:org.apache.karaf.examples/karaf-command-example-features/4.2.9/xml
karaf@root()> feature:install karaf-command-example-provider
karaf@root()> feature:install karaf-command-example
karaf@root()> booking:list
ID | Flight | Customer
---+--------+---------
karaf@root()> booking:add X1 "John O'Connor"
Error executing command: unexpected EOT looking for matching quote: '
karaf@root()> booking:add X1 "John O\'Connor"
karaf@root()> booking:list
ID      | Flight         | Customer
--------+----------------+---------
9198438 | John O\'Connor | X1
karaf@root()> booking:add X2 John\ O\'Connor
karaf@root()> booking:list
ID      | Flight         | Customer
--------+----------------+---------
6573975 | John O'Connor  | X2
9198438 | John O\'Connor | X1

On 2020/07/22 07:50:50, Jean-Baptiste Onofre <jb@nanthrax.net> wrote: 
> Sorry I don’t understand.
> 
> The quote are used as you can see in my previous email (John Doe is without quote but with space).
> 
> Regards
> JB
> 
> > Le 22 juil. 2020 à 09:32, J. Brebec <jeremie.brebec@gmail.com> a écrit :
> > 
> > Thanks.
> > 
> > It works indeed if I doesn't use double quotes and quote every spaces and single quote. It just looks.. not usual to have to use a backslash before a single quote to be valid syntaxically but this backslash is visible by the command.
> > 
> > I have this behavior in all my command (and the camel too), but your workaround helped me, thanks.
> > 
> > 
> > On 2020/07/22 06:29:10, Jean-Baptiste Onofre <jb@nanthrax.net> wrote: 
> >> Hi,
> >> 
> >> I just tested with Karaf Command example:
> >> 
> >> karaf@root()> feature:repo-add mvn:org.apache.karaf.examples/karaf-command-example-features/4.2.9/xml
> >> Adding feature url mvn:org.apache.karaf.examples/karaf-command-example-features/4.2.9/xml
> >> karaf@root()> feature:install karaf-command-example-provider 
> >> karaf@root()> feature:install karaf-command-example 
> >> karaf@root()> booking:list 
> >> ID │ Flight │ Customer
> >> ───┼────────┼─────────
> >> karaf@root()> booking:add AF520 "John Doe"
> >> karaf@root()> booking:list
> >> ID      │ Flight   │ Customer
> >> ────────┼──────────┼─────────
> >> 7187096 │ John Doe │ AF520
> >> 
> >> It just works fine with double quotes as you can see.
> >> 
> >> Backslash also works:
> >> 
> >> karaf@root()> booking:add FOO Other\ Test
> >> karaf@root()> booking:list
> >> ID      │ Flight     │ Customer
> >> ────────┼────────────┼─────────
> >> 2677320 │ Other Test │ FOO
> >> 7187096 │ John Doe   │ AF520
> >> 
> >> Do you have the problem specifically with camel commands or generally speaking ?
> >> 
> >> If it’s only with Camel commands, I will take a look specifically to Camel.
> >> 
> >> Regards
> >> JB
> >> 
> >>> Le 21 juil. 2020 à 15:24, J. Brebec <jeremie.brebec@gmail.com> a écrit :
> >>> 
> >>> A simple example with camel and Karaf 4.2.9:
> >>> 
> >>> karaf@root()> camel:component-list "a'b"
> >>> Error executing command: unexpected EOT looking for matching quote: '
> >>> karaf@root()> camel:component-list "a\'b"
> >>> Camel context a\'b not found.
> >>> 
> >>> Without a quote "a'b" is invalid.
> >>> With a backslash, "a\'b" is valid, however, the command "sees" the backslash (and I don't think every command should handle quoting in an argument?)
> >>> 
> >>> If I use a native gogo(jline?) command, it's working:
> >>> 
> >>> karaf@root()> echo "a\'b"
> >>> a'b
> >>> 
> >>> 
> >>> 
> >>> 
> >>> 
> >>> On 2020/07/21 12:13:42, Jean-Baptiste Onofre <jb@nanthrax.net> wrote: 
> >>>> Hi,
> >>>> 
> >>>> Assuming the last argument is String, did you try " and \" ?
> >>>> 
> >>>> I just try and it works fine for me (on Linux and Mac).
> >>>> 
> >>>> Can you provide some environment details to me please ?
> >>>> 
> >>>> Thanks !
> >>>> Regards
> >>>> JB
> >>>> 
> >>>>> Le 21 juil. 2020 à 10:08, J. Brebec <jeremie.brebec@gmail.com> a écrit :
> >>>>> 
> >>>>> Hello,
> >>>>> 
> >>>>> I have a Karaf shell command which take a String parameters.
> >>>>> How can I call it with a parameters with space and quote ?
> >>>>> 
> >>>>> this doesn't work (the command is not executed with a error about a non-matched quote)
> >>>>> ns:mycmd "xx n'est pas conforme"
> >>>>> 
> >>>>> this doesn't work either: the command is executed, but the backlash is seen by my command
> >>>>> ns:mycmd "xx n\'est pas conforme"
> >>>>> 
> >>>>> I didn't found the right syntax..
> >>>>> 
> >>>>> thanks!
> >>>>> 
> >>>>> Jérémie
> >>>>> 
> >>>> 
> >>>> 
> >> 
> >> 
> 
>