add posixlib

contrib/ports/unix/posixlib/Uninstall.cmake

@@ -0,0 +1,22 @@
+cmake_minimum_required(VERSION 3.13)
+set(MANIFEST "${CMAKE_CURRENT_BINARY_DIR}/install_manifest.txt")
+
+if(NOT EXISTS ${MANIFEST})
+	message(FATAL_ERROR "Cannot find install manifest: '${MANIFEST}'")
+endif()
+
+file(STRINGS ${MANIFEST} files)
+foreach(file ${files})
+	if(EXISTS ${file} OR IS_SYMLINK ${file})
+		message(STATUS "Removing: ${file}")
+
+		execute_process(
+				COMMAND rm -f ${file}
+				RESULT_VARIABLE retcode
+			)
+
+		if(NOT "${retcode}" STREQUAL "0")
+			message(WARNING "Failed to remove: ${file}")
+		endif()
+	endif()
+endforeach(file)