create library and make two examples of usage

I2Csensors/CMakeLists.txt

@@ -0,0 +1,104 @@
+cmake_minimum_required(VERSION 3.9)
+set(PROJ i2csensorsPTH)
+set(MINOR_VERSION "1")
+set(MID_VERSION "1")
+set(MAJOR_VERSION "0")
+set(VERSION "${MAJOR_VERSION}.${MID_VERSION}.${MINOR_VERSION}")
+
+project(${PROJ} VERSION ${VERSION} LANGUAGES C)
+
+# default flags
+set(CMAKE_C_FLAGS "${CFLAGS} -O2")
+set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS}")
+set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS} -Wextra -Wall -Werror -W -Wno-address-of-packed-member")
+set(CMAKE_COLOR_MAKEFILE ON)
+
+option(DEBUG "Compile in debug mode" OFF)
+option(EXAMPLES "Build examples" ON)
+
+if(DEBUG)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Og -g3 -ggdb -Werror")
+    add_definitions(-DEBUG)
+    set(CMAKE_BUILD_TYPE DEBUG)
+    set(CMAKE_VERBOSE_MAKEFILE "ON")
+else()
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O3 -march=native -fdata-sections -ffunction-sections -flto=auto")
+#    add_definitions(-DEBUG)
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections -flto=auto")
+    set(CMAKE_BUILD_TYPE RELEASE)
+endif()
+message("Build type: ${CMAKE_BUILD_TYPE}")
+
+aux_source_directory(${CMAKE_CURRENT_SOURCE_DIR} SOURCES)
+
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(${PROJ} REQUIRED usefull_macros)
+
+# library
+add_library(${PROJ} SHARED ${SOURCES})
+# library header files
+set(LIBHEADER "i2csensorsPTH.h")
+# -I
+include_directories(${${PROJ}_INCLUDE_DIRS})
+# -L
+link_directories(${${PROJ}_LIBRARY_DIRS})
+# -D
+add_definitions(-DPACKAGE_VERSION=\"${VERSION}\" -DMINOR_VERSION=\"${MINOR_VERSION}\"
+        -DMID_VERSION=\"${MID_VERSION}\" -DMAJOR_VERSION=\"${MAJOR_VESION}\")
+# -l
+target_link_libraries(${PROJ} ${${PROJ}_LIBRARIES})
+
+set(PCFILE "${CMAKE_BINARY_DIR}/${PROJ}.pc")
+configure_file("${PROJ}.pc.in" ${PCFILE} @ONLY)
+
+set_target_properties(${PROJ} PROPERTIES VERSION ${VERSION})
+set_target_properties(${PROJ} PROPERTIES PUBLIC_HEADER ${LIBHEADER})
+
+# Installation of the program
+include(GNUInstallDirs)
+install(TARGETS ${PROJ} LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+install(FILES ${PCFILE} DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/pkgconfig)
+
+# EXAMPLES
+if(EXAMPLES)
+    add_subdirectory(examples)
+endif()
+
+###### gettext ######
+if(NOT DEFINED NOGETTEXT)
+    add_definitions(-DGETTEXT)
+    if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+        message("Generate locale files @ make")
+        find_package(Gettext REQUIRED)
+        find_program(GETTEXT_XGETTEXT_EXECUTABLE xgettext)
+        if(NOT GETTEXT_XGETTEXT_EXECUTABLE OR NOT GETTEXT_MSGFMT_EXECUTABLE)
+            message(FATAL_ERROR "xgettext not found")
+        endif()
+        file(MAKE_DIRECTORY ${LCPATH})
+        file(MAKE_DIRECTORY ${LCPATH}/LC_MESSAGES)
+
+        add_custom_command(
+            OUTPUT ${PO_FILE}
+            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+            COMMAND ${GETTEXT_XGETTEXT_EXECUTABLE} --from-code=koi8-r ${SOURCES} -c -k_ -kN_ -o ${PO_FILE}
+            COMMAND sed -i 's/charset=.*\\\\n/charset=koi8-r\\\\n/' ${PO_FILE}
+            COMMAND enconv ${PO_FILE}
+            DEPENDS ${SOURCES}
+        )
+        # we need this to prevent ru.po & .mo from deleting by make clean
+        add_custom_target(
+            RU_FILE
+            COMMAND [ -f ${RU_FILE} ] && ${GETTEXT_MSGMERGE_EXECUTABLE} -Uis ${RU_FILE} ${PO_FILE} || cp ${PO_FILE} ${RU_FILE}
+            DEPENDS ${PO_FILE} ${SOURCES}
+        )
+        add_custom_target(
+            MO_FILE
+            COMMAND make RU_FILE && ${GETTEXT_MSGFMT_EXECUTABLE} ${RU_FILE} -o ${MO_FILE}
+            DEPENDS ${RU_FILE}
+        )
+        add_dependencies(${PROJ} MO_FILE)
+    else() # install .mo file
+        install(FILES ${MO_FILE} DESTINATION "${LOCALEDIR}/ru/LC_MESSAGES")
+    endif()
+endif(NOT DEFINED NOGETTEXT)