The type of the option, as a GOptionArg
If the arg type is G_OPTION_ARG_CALLBACK, then arg_data must point to a GOptionArgFunc callback function, which will be called to handle the extra argument. Otherwise, arg_data is a pointer to a location to store the value, the required type of the location depends on the arg type: - G_OPTION_ARG_NONE: gboolean - G_OPTION_ARG_STRING: gchar* - G_OPTION_ARG_INT: gint - G_OPTION_ARG_FILENAME: gchar* - G_OPTION_ARG_STRING_ARRAY: gchar** - G_OPTION_ARG_FILENAME_ARRAY: gchar** - G_OPTION_ARG_DOUBLE: gdouble If arg type is G_OPTION_ARG_STRING or G_OPTION_ARG_FILENAME, the location will contain a newly allocated string if the option was given. That string needs to be freed by the callee using g_free(). Likewise if arg type is G_OPTION_ARG_STRING_ARRAY or G_OPTION_ARG_FILENAME_ARRAY, the data should be freed using g_strfreev().
The placeholder to use for the extra argument parsed by the option in --help output. The arg_description is translated using the translate_func of the group, see OptionGroup.setTranslationDomain.
the description for the option in --help output. The description is translated using the translate_func of the group, see OptionGroup.setTranslationDomain.
Flags from GOptionFlags
The long name of an option can be used to specify it in a commandline as --long_name. 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 --groupname-long_name.
If an option has a short name, it can be specified -short_name in a commandline. short_name must be a printable ASCII character different from '-', or zero if the option has no short name.
A GOptionEntry struct defines a single option. To have an effect, they must be added to a glib.OptionGroup with OptionContext.addMainEntries or OptionGroup.addEntries.