$ cd /usr/lib/pkgconfig

Administrator@home-25r090xrgo /usr/lib/pkgconfig
$ ls | grep cairo
cairo-ft.pc
cairo-pdf.pc
cairo-png.pc
cairo-ps.pc
cairo-svg.pc
cairo-win32.pc
cairo-xlib-xrender.pc
cairo-xlib.pc
cairo.pc
------------
Administrator@home-25r090xrgo /usr/lib/pkgconfig
$ cat cairo.pc
prefix=/usr
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${prefix}/include

Name: cairo
Description: Multi-platform 2D graphics library
Version: 1.2.0

Requires.private:   xrender >= 0.6   libpng12 freetype2 >= 8.0.2 fontconfig
Libs:  -L${libdir} -lcairo
Cflags:  -I${includedir}/cairo

------------------
Administrator@home-25r090xrgo /usr/lib/pkgconfig
$ ls $prefix/include | grep cairo
cairo
Administrator@home-25r090xrgo /usr/lib/pkgconfig
$ ls $exec_prefix/lib | grep cairo
libcairo.a
libcairo.dll.a
libcairo.la

----------------

Administrator@home-25r090xrgo /usr/lib/pkgconfig
$ cd /usr/include/cairo

Administrator@home-25r090xrgo /usr/include/cairo
$ ls
cairo-features.h  cairo-pdf.h  cairo-win32.h         cairo.h
cairo-ft.h        cairo-ps.h   cairo-xlib-xrender.h
cairo-glitz.h     cairo-svg.h  cairo-xlib.h