Re: Lisp object that refers to a C struct

[Stefan Monnier <monnier@iro.umontreal.ca>]

> It seems like a pseudo-vector is used for this, but in my case it
> looks like an overkill: my struct has no Lisp members.

You can use either a pseudo-vector, or s Lisp_Misc.

> There's Lisp_Save_Value, which looks very promising,

Lisp_Save_Value is a Lisp_Misc.

> but why does its documentation say it's for record_unwind_protect?
> Is there anything in it which would preclude its use
> outside unwinding?

It doesn't look very pretty when printed, so it's generally better not
to expose it to users too much.  If your value will usually not be
visible to Elisp code, then Lisp_Save_Value is perfectly fine.
Otherwise, better define your own type so that its printed
representation can be more helpful, indicating what it's used for (I
presume it's for a file-watch-descriptor).


        Stefan