The libbytesize is a C library with GObject introspection support that facilitates work with sizes in bytes. Be it parsing the input from users or producing a nice human readable representation of a size in bytes this library takes localization into account. It also provides support for sizes bigger than MAXUINT64.
This is a companion discussion topic for the original entry at https://copr.fedorainfracloud.org/coprs/vpodzime/libbytesize/