Date: Tue, 7 Jun 2016 20:06:05 +0200 From: Polytropon <freebsd@edvax.de> To: Murk Fletcher <murk.fletcher@gmail.com> Cc: User Questions <freebsd-questions@freebsd.org> Subject: Re: rc scripting trouble with quotes Message-ID: <20160607200605.6761fc0e.freebsd@edvax.de> In-Reply-To: <CAH=3fONuy_afgSHGMO7YafN2cX8O9V9ULV3-%2BQq86eRxaJXysw@mail.gmail.com> References: <CAH=3fONuy_afgSHGMO7YafN2cX8O9V9ULV3-%2BQq86eRxaJXysw@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 7 Jun 2016 14:04:27 +0200, Murk Fletcher wrote:
> Hi!
>
> How do I access a variable inside quotes? Right now I'm having some
> difficulties:
>
> stop_cmd="cd ${myapp} && \
> ${myapp} stop && \
> kill -9 `cat ${myapp}/tmp/pids/example.pid`"
>
> Returns:
>
> cat: ${myapp}/tmp/pids/example.pid: No such file or directory
Have you checked the actual value of that expression? For testing,
insert something like
echo ${myapp}/tmp/pids/example.pid
to see if you _really_ get the file name you're expecting.
> I hear it would work better with double quotes, [...]
There is no "work better" here: If you use double quotes, variables
will be expanded; if you use single quotes, they will not. Double
quotes are usually needed when a path contains spaces (because the
space character is the argument separator, while it also is a valid
character for file names).
> [...] but that would add a
> double-double quote at the end:
>
> stop_cmd="cd ${myapp} && \
> ${myapp} stop && \
> kill -9 "$(cat -- ${myapp}/tmp/pids/example.pid)""
You could use qupting, \", but that probably won't work as intended.
You need to use quotes because the value you assign to $stop_cmd
contains spaces. You could use quoted spaces, \ , to get rid of
them, but that makes the whole thing nearly unreadable and will
probably introduce more problems. :-)
> Is there a way I could wrap the contents of `stop_cmd` inside a function or
> something?
Basically, your initial assignment looks correct, there surely
is a different problem (maybe with the evaluation of ${myapp}.
As it as already been mentioned, /etc/rc.subr should do what's
needed to stop a program, maybe you don't even need to do this
manually.
--
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20160607200605.6761fc0e.freebsd>