rc scripting trouble with quotes

[Murk Fletcher]

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

I hear it would work better with double quotes, 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)""

Is there a way I could wrap the contents of `stop_cmd` inside a function or
something?

Thanks!

--Murk

https://freebsd.org/doc/en/articles/rc-scripting/rcng-dummy.html

[Murk Fletcher]

For what it's worth I ended up with the whole function thing and it's
working perfectly:

dummy_stop() {
cd ${myapp} &&
${myapp} stop &&
kill -9 "$(cat -- ${myapp}/tmp/pids/example.pid)"
}

stop_cmd="dummy_stop"

Thanks!

--Murk

Post by Murk Fletcher
Hi!
How do I access a variable inside quotes? Right now I'm having some
stop_cmd="cd ${myapp} && \
${myapp} stop && \
kill -9 `cat ${myapp}/tmp/pids/example.pid`"
cat: ${myapp}/tmp/pids/example.pid: No such file or directory
I hear it would work better with double quotes, but that would add a
stop_cmd="cd ${myapp} && \
${myapp} stop && \
kill -9 "$(cat -- ${myapp}/tmp/pids/example.pid)""
Is there a way I could wrap the contents of `stop_cmd` inside a function
or something?
Thanks!
--Murk
https://freebsd.org/doc/en/articles/rc-scripting/rcng-dummy.html

[RW via freebsd-questions]

On Tue, 7 Jun 2016 14:04:27 +0200

Post by Murk Fletcher
Hi!
How do I access a variable inside quotes? Right now I'm having some
stop_cmd="cd ${myapp} && \
${myapp} stop && \
kill -9 `cat ${myapp}/tmp/pids/example.pid`"

Are you sure you really need to do this? Stopping daemons is a basic
part of what rc.subr does.

[Polytropon]

Post by Murk Fletcher
Hi!
How do I access a variable inside quotes? Right now I'm having some
stop_cmd="cd ${myapp} && \
${myapp} stop && \
kill -9 `cat ${myapp}/tmp/pids/example.pid`"
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.

Post by Murk Fletcher
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).

Post by Murk Fletcher
[...] but that would add a
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. :-)

Post by Murk Fletcher
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.