GTK3 application docs, unclear statement

[Stefan Salewski <mail ssalewski de>]

In

https://developer.gnome.org/gtk3/stable/ch01s04.html#id-1.2.3.12.5

we have

Before we can make use of this schema in our application, we need to
compile it into the binary form that GSettings expects. GIO provides
 macros to do this in autotools-based projects.

I have still no idea what these "macros" are. The link does not work
unfortunately, and Google search for that terms did not really helped.

Earlier in that documents this command was mentioned

glib-compile-resources example app.gresource.xml --target=resources.c -
-generate-source

Is that the "macro" ?