GLib.OptionEntry.long_name
OptionEntry.long_name: String (Read)
The long name of an option can be used to specify it in a commandline as --<replaceable>long_name</replaceable>. Every option must have a long name. To resolve conflicts if multiple option groups contain the same long name, it is also possible to specify the option as --<replaceable>groupname</replaceable>-<replaceable>long_name</replaceable>.