Here are the classes, structs, unions and interfaces with brief descriptions:

ChecksumType	CHECKSUM_MD5: Use the MD5 hashing algorithm CHECKSUM_SHA1: Use the SHA-1 hashing algorithm CHECKSUM_SHA256: Use the SHA-256 hashing algorithm
Gio::AppInfo	Application information, to describe applications installed on the system, and launch them
Gio::AppLaunchContext	This is used to handle, for instance, startup notification and launching of the new application on the same screen as the launching window
Gio::AsyncInitable	AsyncInitable - Asynchronously failable object initialization interface
Gio::AsyncResult	Provides a base class for implementing asynchronous function results
Gio::BufferedInputStream	The buffered input stream implements FilterInputStream and provides for buffered reads
Gio::BufferedOutputStream	The buffered output stream implements FilterOutputStream and provides for buffered writes
Gio::Cancellable	Allows actions to be cancelled
Gio::Credentials	An object containing credentials
Gio::DataInputStream	An implementation of BufferedInputStream that allows for high-level data manipulation of arbitrary data (including binary operations)
Gio::DataOutputStream	An implementation of BufferedOutputStream that allows for high-level data manipulation of arbitrary data (including binary operations)
Gio::DBus::AnnotationInfo	Stores information about an annotation
Gio::DBus::ArgInfo	ArgInfo - Stores information about an argument for a method or a signal
Gio::DBus::AuthObserver	Ah object used for authenticating connections
Gio::DBus::Connection	A D-Bus Connection
Gio::DBus::Error
Gio::DBus::InterfaceInfo	Stores information about a D-Bus interface
Gio::DBus::InterfaceVTable	This represents a virtual table for handling properties and method calls for a D-Bus interface
Gio::DBus::Message	A type for representing D-Bus messages that can be sent or received on a Connection
Gio::DBus::MethodInfo	Stores information about a method on an D-Bus interface
Gio::DBus::MethodInvocation	An Object for handling remote calls
Gio::DBus::NodeInfo	NodeInfo - Stores information about nodes in a remote object hierarchy
Gio::DBus::PropertyInfo	Stores information about a property on a D-Bus interface
Gio::DBus::Proxy	A client-side proxy
Gio::DBus::Server	This is a helper for listening to and accepting D-Bus connections
Gio::DBus::SignalInfo	Stores information about a signal on a D-Bus interface
Gio::DBus::SubtreeVTable	This represents a virtual table for subtrees registered with Gio::DBus::Connection::register_subtree()
Gio::DesktopAppInfo	DesktopAppInfo is an implementation of AppInfo based on desktop files
Gio::Drive	Virtual File System drive management
Gio::Emblem	An object for emblems
Gio::EmblemedIcon	Icons with Emblems
Gio::Error	Exception class for giomm errors
Gio::File	File and directory handling
Gio::FileAttributeInfo	Information about a specific attribute - see FileAttributeInfoList
Gio::FileAttributeInfoList	Key-Value paired file attributes
Gio::FileAttributeMatcher	FileAttributeMatcher allows for searching through a FileInfo for attributes
Gio::FileEnumerator	Enumerated Files Routines
Gio::FileIcon	FileIcon specifies an icon by pointing to an image file to be used as icon
Gio::FileInfo	FileInfo implements methods for getting information that all files should contain, and allows for manipulation of extended attributes
Gio::FileInputStream	FileInputStream provides input streams that take their content from a file
Gio::FileIOStream	FileIOStream provides input streams that take their content from a file
Gio::FileMonitor	Monitors a file or directory for changes
Gio::FilenameCompleter	Completes partial file and directory names given a partial string by looking in the file system for clues
Gio::FileOutputStream	FileOutputStream provides output streams that write their content to a file
Gio::FilterInputStream	Filter Input Stream
Gio::FilterOutputStream	Filter Output Stream
Gio::Icon	This is a very minimal interface for icons
Gio::InetAddress	An IPv4/IPv6 address
Gio::InetSocketAddress	Internet SocketAddress
Gio::Initable	Failable object initialization interface
Gio::InputStream	Base class for implementing streaming input
Gio::IOStream
Gio::LoadableIcon	Extends the Icon interface and adds the ability to load icons from streams
Gio::MemoryInputStream	MemoryInputStream implements InputStream for arbitrary memory chunks
Gio::MemoryOutputStream	Streaming output operations on memory chunks
Gio::Mount	The Mount interface represents user-visible mounts
Gio::MountOperation	Authentication methods for mountable locations
Gio::NetworkAddress	A SocketConnectable for resolving hostnames
Gio::NetworkService	A GSocketConnectable for resolving SRV records
Gio::OutputStream	Base class for implementing streaming output
Gio::Proxy	Proxy - Interface for proxy handling
Gio::ProxyAddress	ProxyAddress - An internet address with proxy information
Gio::ProxyResolver	ProxyResolver - Asynchronous and cancellable network proxy resolver
Gio::Resolver	Asynchronous and cancellable DNS resolver
Gio::ResolverError
Gio::Seekable	Stream seeking interface
Gio::Settings	A high-level API for application settings
Gio::Socket	Low-level socket object
Gio::SocketAddress	Abstract base class representing endpoints for socket communication
Gio::SocketAddressEnumerator	Enumerator type for objects that contain or generate SocketAddresses
Gio::SocketClient	Helper for connecting to a network service
Gio::SocketConnectable	Interface for potential socket endpoints
Gio::SocketConnection	A socket connection
Gio::SocketControlMessage	SocketControlMessage - A Socket control message
Gio::SocketListener	Helper for accepting network client connections
Gio::SocketService	Make it easy to implement a network service
Gio::SrvTarget	DNS SRV record target
Gio::TcpConnection	A TCP SocketConnection
Gio::ThemedIcon	Icon theming support ThemedIcon is an implementation of Gio::Icon that supports icon themes
Gio::ThreadedSocketService	A threaded GSocketService
Gio::UnixConnection	A Unix domain SocketConnection
Gio::UnixCredentialsMessage	UnixCredentialsMessage - A SocketControlMessage containing credentials
Gio::UnixFDList	UnixFDList - An object containing a set of UNIX file descriptors
Gio::UnixFDMessage	UnixFDMessage — A GSocketControlMessage containing a GUnixFDList
Gio::UnixInputStream	UnixInputStream implements InputStream for reading from a unix file descriptor, including asynchronous operations
Gio::UnixOutputStream	UnixOutputStream implements OutputStream for writing to a a unix file descriptor, including asynchronous operations
Gio::UnixSocketAddress	UnixSocketAddress - UNIX SocketAddress
Gio::Volume	The Volume interface represents user-visible objects that can be mounted
Gio::VolumeMonitor	Monitors a file or directory for changes
Glib::ArrayHandle< T, Tr >	This is an intermediate type
Glib::ArrayHandle< bool, Container_Helpers::TypeTraits< bool > >
Glib::ArrayHandler< T, Tr >	A utility for converting between std::vector and plain C arrays
Glib::ArrayHandler< bool >
Glib::BalancedTree< K, V >	Balanced Binary Trees — a sorted collection of key/value pairs optimized for searching and traversing in order
Glib::Checksum	Computes the checksum for data
Glib::Cond	An opaque data structure to represent a condition
Glib::Container_Helpers::ArrayHandleIterator< Tr >
Glib::Container_Helpers::ArrayIterator< Tr >
Glib::Container_Helpers::ArrayKeeper< Tr >	A keeper class for C array
Glib::Container_Helpers::GListKeeper< Tr >	A keeper class for GList
Glib::Container_Helpers::GSListKeeper< Tr >	A keeper class for GSList
Glib::Container_Helpers::ListHandleIterator< Tr >
Glib::Container_Helpers::ListIterator< Tr >
Glib::Container_Helpers::SListHandleIterator< Tr >
Glib::Container_Helpers::SListIterator< Tr >
Glib::Container_Helpers::TypeTraits< T >	Generic TypeTraits implementation
Glib::Container_Helpers::TypeTraits< Glib::RefPtr< Gio::Drive > >	This specialization of TypeTraits exists because the default use of Glib::wrap(GObject*), instead of a specific Glib::wrap(GSomeInterface*), would not return a wrapper for an interface
Glib::Container_Helpers::TypeTraits< Glib::RefPtr< Gio::File > >	This specialization of TypeTraits exists because the default use of Glib::wrap(GObject*), instead of a specific Glib::wrap(GSomeInterface*), would not return a wrapper for an interface
Glib::Container_Helpers::TypeTraits< Glib::RefPtr< Gio::Mount > >	This specialization of TypeTraits exists because the default use of Glib::wrap(GObject*), instead of a specific Glib::wrap(GSomeInterface*), would not return a wrapper for an interface
Glib::Container_Helpers::TypeTraits< Glib::RefPtr< Gio::Volume > >	This specialization of TypeTraits exists because the default use of Glib::wrap(GObject*), instead of a specific Glib::wrap(GSomeInterface*), would not return a wrapper for an interface
Glib::ConvertError	Exception class for charset conversion errors
Glib::Date	Julian calendar date
Glib::DateTime	DateTime - A structure representing Date and Time
Glib::Dir	Utility class representing an open directory
Glib::DirIterator	The iterator type of Glib::Dir
Glib::Dispatcher	Signal class for inter-thread communication
Glib::Error
Glib::Exception
Glib::FileError	Exception class for file-related errors
Glib::HelperList< T_Child, T_CppElement, T_Iterator >
Glib::IConv	Thin iconv() wrapper
Glib::IdleSource
Glib::Interface
Glib::IOChannel	IOChannel aims to provide portable I/O support for files, pipes and sockets, and to integrate them with the GLib main event loop
Glib::IOChannelError	Exception class for IOChannel errors
Glib::IOSource
Glib::KeyFile	This class lets you parse, edit or create files containing groups of key-value pairs, which we call key files for lack of a better name
Glib::KeyFileError	Exception class for KeyFile errors
Glib::ListHandle< T, Tr >	This is an intermediate type
Glib::ListHandler< T, Tr >	A utility for converting between std::vector and GList
Glib::MainContext	Main context
Glib::MainLoop
Glib::Markup::AttributeKeyLess	Binary predicate used by Markup::Parser::AttributeMap
Glib::Markup::ParseContext	A parse context is used to parse marked-up documents
Glib::Markup::Parser	The abstract markup parser base class
Glib::MarkupError	Exception class for markup parsing errors
Glib::MatchInfo	MatchInfo - MatchInfo is used to retrieve information about the regular expression match which created it
Glib::Module	Dynamic Loading of Modules These functions provide a portable way to dynamically load object files (commonly known as 'plug-ins')
Glib::Mutex	Represents a mutex (mutual exclusion)
Glib::Mutex::Lock	Utility class for exception-safe mutex locking
Glib::NodeTree< T >	N-ary Trees - trees of data with any number of branches The NodeTree class and its associated functions provide an N-ary tree data structure, in which nodes in the tree can contain arbitrary data
Glib::Object
Glib::ObjectBase	Glib::ObjectBase is a common base class for Objects and Interfaces
Glib::OptionContext	An OptionContext defines which options are accepted by the commandline option parser
Glib::OptionEntry	An OptionEntry defines a single option
Glib::OptionError	Exception class for options
Glib::OptionGroup	An OptionGroup defines the options in a single group
Glib::PatternSpec
Glib::PollFD
Glib::Private< T >
Glib::Property< T >
Glib::PropertyBase
Glib::PropertyProxy< T >	A PropertyProxy can be used to get and set the value of an object's property
Glib::PropertyProxy_Base
Glib::PropertyProxy_ReadOnly< T >	See PropertyProxy()
Glib::PropertyProxy_WriteOnly< T >	See PropertyProxy()
Glib::Quark
Glib::QueryQuark	Quarks are unique IDs in Glib for strings for use in hash table lookups
Glib::Rand
Glib::RecMutex
Glib::RecMutex::Lock	Utility class for exception-safe locking of recursive mutexes
Glib::RefPtr< T_CppObject >	RefPtr<> is a reference-counting shared smartpointer
Glib::Regex	Perl-compatible regular expressions - matches strings against regular expressions
Glib::RegexError	Exception class for Regex
Glib::RWLock
Glib::RWLock::ReaderLock	Utility class for exception-safe locking of read/write locks
Glib::RWLock::WriterLock	Utility class for exception-safe locking of read/write locks
Glib::Sequence< Iterator >	Utility class holding an iterator sequence
Glib::ShellError	Exception class for shell utility errors
Glib::SignalChildWatch
Glib::SignalIdle
Glib::SignalIO
Glib::SignalProxy0< R >	Proxy for signals with 0 arguments
Glib::SignalProxy1< R, P1 >	Proxy for signals with 1 arguments
Glib::SignalProxy2< R, P1, P2 >	Proxy for signals with 2 arguments
Glib::SignalProxy3< R, P1, P2, P3 >	Proxy for signals with 3 arguments
Glib::SignalProxy4< R, P1, P2, P3, P4 >	Proxy for signals with 4 arguments
Glib::SignalProxy5< R, P1, P2, P3, P4, P5 >	Proxy for signals with 5 arguments
Glib::SignalProxy6< R, P1, P2, P3, P4, P5, P6 >	Proxy for signals with 6 arguments
Glib::SignalProxyBase
Glib::SignalProxyNormal	The SignalProxy provides an API similar to sigc::signal that can be used to connect sigc::slots to glib signals
Glib::SignalProxyProperty	Use the connect() method, with sigc::ptr_fun() or sig::mem_fun() to connect signals to signal handlers
Glib::SignalTimeout
Glib::SListHandle< T, Tr >	This is an intermediate type
Glib::SListHandler< T, Tr >	A utility for converting between std::vector and GSList
Glib::Source
Glib::SpawnError	Exception class for errors occuring when spawning processes
Glib::StaticMutex	Like Glib::Mutex, but can be defined at compile time
Glib::StaticPrivate< T >
Glib::StaticRecMutex	Like Glib::RecMutex, but can be defined at compile time
Glib::StaticRWLock	Like Glib::RWLock, but can be defined at compile time
Glib::StreamIOChannel
Glib::Thread	Represents a running thread
Glib::Thread::Exit	Exception class used to exit from a thread
Glib::ThreadError	Exception class for thread-related errors
Glib::ThreadPool	A pool of threads to execute work concurrently
Glib::TimeoutSource
Glib::Timer	Portable stop watch interface
Glib::TimeVal	Glib::TimeVal is a wrapper around the glib structure GTimeVal
Glib::TimeZone	TimeZone - A structure representing a time zone
Glib::ustring	Glib::ustring has much the same interface as std::string, but contains Unicode characters encoded as UTF-8
Glib::ustring_Iterator< T >	The iterator type of Glib::ustring
Glib::Value< T >	Generic value implementation for custom types
Glib::Value< bool >
Glib::Value< char >
Glib::Value< const T* >	Specialization for pointers to const instances of any type
Glib::Value< double >
Glib::Value< float >
Glib::Value< Glib::ustring >	Specialization for UTF-8 strings
Glib::Value< int >
Glib::Value< long >
Glib::Value< long long >
Glib::Value< std::string >	Specialization for strings
Glib::Value< T* >	Specialization for pointers to instances of any type
Glib::Value< unsigned char >
Glib::Value< unsigned int >
Glib::Value< unsigned long >
Glib::Value< unsigned long long >
Glib::Value< void* >
Glib::Value_Boxed< T >
Glib::Value_Enum< T >	Base class of Glib::Value<T> specializations for enum types
Glib::Value_Flags< T >	Base class of Glib::Value<T> specializations for flags types
Glib::Value_Pointer< T, PtrT >
Glib::ValueArray	A container structure to maintain an array of generic values
Glib::ValueBase
Glib::ValueBase_Boxed
Glib::ValueBase_Enum
Glib::ValueBase_Flags
Glib::ValueBase_Object
Glib::ValueBase_String
Glib::Variant< T >	Template class used for the specialization of the Variant<> classes
Glib::Variant< bool >	Specialization of Glib::Variant containing a bool type
Glib::Variant< double >	Specialization of Glib::Variant containing a double type
Glib::Variant< gint16 >	Specialization of Glib::Variant containing a gint16 type
Glib::Variant< gint32 >	Specialization of Glib::Variant containing a gint32 type
Glib::Variant< gint64 >	Specialization of Glib::Variant containing a gint64 type
Glib::Variant< Glib::ustring >	Specialization of Variant containing a Glib::ustring, for variants of type string, bytestring, object path, or signature
Glib::Variant< guint16 >	Specialization of Glib::Variant containing a guint16 type
Glib::Variant< guint32 >	Specialization of Glib::Variant containing a guint32 type
Glib::Variant< guint64 >	Specialization of Glib::Variant containing a guint64 type
Glib::Variant< std::map< K, V > >	Specialization of Variant containing a dictionary (a map of (key, value) elements)
Glib::Variant< std::string >	Specialization of Variant containing a std::string, for variants of type bytestring, object path, or signature
Glib::Variant< std::vector< Glib::ustring > >	Specialization of Variant containing an array of UTF-8 capable strings
Glib::Variant< std::vector< std::string > >	Specialization of Variant containing an array of non-UTF-8 strings (byte string arrays)
Glib::Variant< std::vector< T > >	Specialization of Variant containing an array of items
Glib::Variant< unsigned char >	Specialization of Glib::Variant containing a unsigned char type
Glib::Variant< VariantBase >	Specialization of Variant containing a VariantBase
Glib::VariantBase	This is the base class for all Variant types
Glib::VariantContainerBase	The base class from which multiple-item Variants derive, such as Variants containing tuples or arrays
Glib::VariantIter	VariantIter - An opaque data structure used to iterate through VariantBase containers such as arrays
Glib::VariantStringBase	Base class from which string variant classes derive
Glib::VariantType	VariantType - The VariantBase type system
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