[Fontconfig] @CONFIGDIR@ (usually /etc/fonts/conf.d) could be recorded in fontconfig.pc?

[suzuki toshiya]

Hi all,

Is it possible to record the value of @CONFIGDIR@ (usually /etc/fonts/conf.d)
into fontconfig.pc?
Now I'm playing with a package trying to insert a font substitution rule into
the directory
(cups-filter), and wondering how to identify the directory by autotools.

According to configure.ac of fontconfig, it is usually set to
@BASECONFIGDIR@/conf.d,
but the developer can set something different, by giving "--with-configdir".

Current fontconfig.pc records @BASECONFIGDIR@ value with the variable "confdir",
but @CONFIGDIR@ is not recorded.

I'm not sure whether the insertion of font search/substitution rule by external
package is acceptable behaviour or not,
but I think the recording of the manually configurable values into pkg-config
file is basically good idea.

So I want to suggest to record the value... but what is the best name for the
variable?
I want to hear your comments to draft a small patch.

Regards,
mpsuzuki

P.S.
BTW, I'm afraid that @XMLDIR@ is no longer used..?