>  Yes - but since you're using s6 anyway, you also have s6-setlock,
> which features more options than flock. ;)
I will happily use s6-setlock!

That said, it might be of interest to you, that s6-setlock does not 
appear here: https://skarnet.org/software/s6/index.html.


I wish you a nice week!


Paul