CMake pkg-config .pc.in generate template

CMakeLists.txt

# this fragment generates build/my_package.pc
# 
# cmake -B build -DCMAKE_INSTALL_PREFIX=~/mylib

cmake_minimum_required(VERSION 3.0)

project(mylib 
LANGUAGES C
HOMEPAGE_URL https://github.invalid/username/mylib
DESCRIPTION "example library"
VERSION 1.1.2)

add_library(mine mine.c)
add_library(support support.c)

set(target1 mine)
set(target2 support)

set(pc_libs_private)
set(pc_req_private)
set(pc_req_public) 

configure_file(my_package.pc.in my_package.pc @ONLY) 

my_package.pc.in

# this template is filled-in by CMake `configure_file(... @ONLY)`
# the `@....@` are filled in by CMake configure_file(), 
# from variables set in your CMakeLists.txt or by CMake itself
#
# Good tutoral for understanding .pc files: 
# https://people.freedesktop.org/~dbn/pkg-config-guide.html

prefix="@CMAKE_INSTALL_PREFIX@"
exec_prefix="${prefix}"
libdir="${prefix}/lib"
includedir="${prefix}/include"

Name: @PROJECT_NAME@
Description: @CMAKE_PROJECT_DESCRIPTION@
URL: @CMAKE_PROJECT_HOMEPAGE_URL@
Version: @PROJECT_VERSION@
Requires: @pc_req_public@
Requires.private: @pc_req_private@
Cflags: -I"${includedir}"
Libs: -L"${libdir}" -l@target1@ -l@target2@
Libs.private: -L"${libdir}" -l@target1@ -l@target2@ @pc_libs_private@

Additional note on the subject: when users use cmake --install . with a --prefix, this pkg-config file template will have the wrong CMAKE_INSTALL_PREFIX -> here's a discussion (with one solution) on that: https://discourse.cmake.org/t/how-to-generate-pc-pkg-config-file-supporting-prefix-of-the-cmake-install/4109