Re: [PATCH] Added basic file system watching support.

[Eli Zaretskii]

> From: Michael Albinus <address@hidden>
> Cc: address@hidden,  address@hidden,  address@hidden,  address@hidden
> Date: Tue, 11 Dec 2012 09:19:10 +0100
> 
> >> Could we extend the interface of `inotify-rm-watch' to add a file name?
> >
> > Why do you need an extension?  This is Lisp: we could pass the file
> > name _as_ the descriptor.  Since the remote file handler will take
> > care of the call anyway, it will assign the correct meaning to the
> > descriptor.
> 
> Sure, that would be sufficient for Tramp. I had the impression, that a
> more complex structure as descriptor was chosen, because there could be
> several `inotify-add-watch' calls for the *same* file, being different
> in the aspect or the callback function.

Then Tramp could maintain its own data structure for watched files,
and give each watch a unique identifier, like (FILENAME . NUMBER), or
just NUMBER, or whatever.

IOW, the DESCRIPTOR is an opaque data type, which the implementation
back-end, and the back-end alone, can and should interpret.