This inheritance list is sorted roughly, but not completely, alphabetically:

Cost::ThreadQueue::_data
Cost::File::_fcb
Cost::Assoc	This class is used to associate (object) pointers with named strings
Cost::AtomicCounter	Offers thread-safe manipulation of an integer counter
Cost::BaseObject	BaseObject
Cost::Cancellation	A class to automatically set the thread cancellation mode of a member function
Cost::CommandOption	CommandOption is the base class for all command line options
Cost::CommandOptionNoArg	CommandOption type for flags
Cost::CommandOptionWithArg	Derived class of CommandOption for options that have a value associated with them
Cost::CommandOptionArg	Class for options with an argument e.g
Cost::CommandOptionCollect	It only makes sense to have a single one of these set and it is also exclusive with CommandOptionRest
Cost::CommandOptionRest	It only makes sense to have a single one of these set and it is exclusive with CommandOptionCollect
Cost::CommandOptionParse	This is the CommandOptionParse interface class
Cost::Conditional	A conditional variable synchcronization object for one to one and one to many signal and control events between processes
Cost::Buffer	The buffer class represents an IPC service that is built upon a buffer of fixed capacity that can be used to transfer objects between one or more producer and consumer threads
Cost::FixedBuffer	A buffer class that holds a known capacity of fixed sized objects defined during creation
Cost::Counter< T >	The counter template is used for generic objects which act as automatic counters
Cost::Date	Uses a julian date representation of the current year, month, and day
Cost::DateNumber	A number class that manipulates a string buffer that is also a date
Cost::Datetime	Uses a julian date representation of the current year, month, and day and a integer representation of the current time
Cost::Keydata::Define
Cost::DirTree	A generic class to walk a hierarchical directory structure
Cost::DSO	The DSO dynamic loader class is used to load object files
Cost::Engine	Engine
Cost::Event	Implements a feature originally found in the WIN32 API; event notification
Cost::File
Cost::Dir	A low level portable directory class
Cost::RandomFile	The purpose of this class is to define a base class for low level random file access that is portable between Win32 and Posix systems
Cost::MappedFile	Create and map a disk file into memory
Cost::SharedFile	This class defines a database I/O file service that can be shared by multiple processes
Cost::ThreadFile	This class defines a database I/O file service that can be shared by multiple threads
Cost::HEXdump	Produces a dump of a buffer in a hexdump way with its code Ascii translation and relative buffer address
Cost::AppLog::Ident	Ident class that represents module name
Cstd::iostream
Cost::TCPStream	TCP streams are used to represent TCP client connections to a server by TCP protocol servers for accepting client connections
Cost::SSLStream
Cost::TCPSession	The TCP session is used to primarily to represent a client connection that can be managed on a seperate thread
Cost::URLStream	A URL processing version of TCPStream
Cost::TTYStream	TTY streams are used to represent serial connections that are fully "streamable" objects using C++ stream classes and friends
Cost::TTYSession	The TTYSession aggragates a TTYStream and a Common C++ Thread which is assumed to be the execution context that will be used to perform actual I/O operations
Cost::ttystream	A more natural C++ "ttystream" class for use by non-threaded applications
Cost::UnixStream	Unix streams are used to represent Unix domain client connections to a local server for accepting client connections
Cost::UnixSession	The Unix domain session is used to primarily to represent a client connection that can be managed on a seperate thread
Cost::unixstream	A more natural C++ "unixstream" class for use by non-threaded applications
Cost::IPV4Address	The network name and address objects are all derived from a common IPV4Address base class
Cost::IPV4Broadcast	The broadcast address object is used to store the broadcast address for a specific subnet
Cost::IPV4Host	This object is used to hold the actual and valid internet address of a specific host machine that will be accessed through a socket
Cost::IPV4Mask	Internet addresses used specifically as masking addresses (such as " 255.255.255.0") are held in the IPV4Mask derived object
Cost::IPV4Multicast	A specialization of IPV4Address that provides address validation for multicast addresses
Cost::IPV4Cidr	The CIDR class is used to support routing tables and validate address policies
Cost::IPV4Validator	Classes derived from IPV4Address would require an specific validator to pass to the IPV4Address constructor
Cost::IPV4MulticastValidator	Class for the function object that validates multicast addresses
Cost::IPV6Address	The network name and address objects are all derived from a common IPV6Address base class
Cost::IPV6Broadcast	The broadcast address object is used to store the broadcast address for a specific subnet
Cost::IPV6Host	This object is used to hold the actual and valid internet address of a specific host machine that will be accessed through a socket
Cost::IPV6Mask	Internet addresses used specifically as masking addresses (such as " 255.255.255.0") are held in the IPV6Mask derived object
Cost::IPV6Multicast	A specialization of IPV6Address that provides address validation for multicast addresses
Cost::IPV6Cidr	The CIDR class is used to support routing tables and validate address policies
Cost::IPV6Validator	Classes derived from IPV6Address would require an specific validator to pass to the IPV6Address constructor
Cost::IPV6MulticastValidator	Class for the function object that validates multicast addresses
Cstd::istream
Cost::IZStream
Cost::StringTokenizer::iterator	The input forward iterator for tokens
Cost::Keydata::Keysym
Cost::Keydata::Keyval
Cost::LinkedDouble	Self managed double linked list object chain
Cost::LinkedSingle	Self managed single linked list object chain
Cost::Lockfile	This class is used to create a "named" lock entity that can be used to control access to a resource between multiple processes
Cost::MapIndex	The MapIndex allows linear access into a MapTable, that otherwise could have its elements being retrieved only by key
Cost::MapObject	The MapObject is a base class which can be used to make a derived class operate on a MapTable
Cost::MemPager	The memory pager is used to allocate cumulative memory pages for storing object specific "persistant" data that is presumed to persist during the life of a given derived object
Cost::Keydata	Keydata objects are used to load and hold "configuration" data for a given application
Cost::SharedMemPager	The shared mempager uses a mutex to protect key access methods
Cost::StackPager	The StackPager provides a repository to stash and retrieve working data in last-in-first-out order
Cost::MemPagerObject	This class is used to create derived classes which are constructed within a memory pager pool
Cost::MIMEItemPart	This is used to attach an item part to a MIME multipart document that is being streamed
Cost::MIMEFormData	This is a document part type for use in submitting multipart form data to a web server
Cost::MIMEMultipart	A container class for multi-part MIME document objects which can be streamed to a std::ostream destination
Cost::MIMEMultipartForm	The Multipart form is a MIME multipart document specific for the construction and delivery of form data to a web server through a post method
Cost::Mutex	Used to protect a section of code so that at any given time only a single thread can perform the protected operation
Cost::MapTable	A map table allows for entities to be mapped (hash index) onto it
Cost::MutexCounter	The Mutex Counter is a counter variable which can safely be incremented or decremented by multiple threads
Cost::RandomFile	The purpose of this class is to define a base class for low level random file access that is portable between Win32 and Posix systems
Cost::Runlist	A runlist is used to restrict concurrent exection to a limited set of concurrent sessions, much like a semaphore
Cost::SerialService	The SerialService is a thead service object that is meant to service attached serial ports
Cost::SharedMemPager	The shared mempager uses a mutex to protect key access methods
Cost::SocketService	The SocketService is a thread pool object that is meant to service attached socket ports
Cost::ThreadQueue	Somewhat generic queue processing class to establish a producer consumer queue
Cost::MutexLock	Used to protect a section of code so that at any given time only a single thread can perform the protected operation
Cost::NetworkDeviceInfo	Network device information class
Cost::StringTokenizer::NoSuchElementException	Exception thrown, if someone tried to read beyond the end of the tokens
Cost::Number	A number manipulation class
Cost::DateNumber	A number class that manipulates a string buffer that is also a date
Cost::ZNumber
Cost::objCounter< T >	Generic template class for creating classes which maintain an active count of the number of instances currently in active use
Cost::objList< T, K >	Used to create and manage a single linked list of objects of a common type
Cost::objMap< T, K, S >	Used to create and manage a hash index of objects through a common type
Cost::objMap< T, keystring, S >
Cost::keyMap< T, S >
Cost::objSync< T >	Generic template to create objects of a common base type which share a static mutex so that all instances of the class have a global lock
Costream
Cost::AppLog	Application logger is a class that implements a logger that can be used by applications to save log file somewhere on the system
Cstd::ostream
Cost::Digest	The digest base class is used for implementing and deriving one way hashing functions
Cost::CRC16Digest	A crc16 collection/compution hash accumulator class
Cost::CRC32Digest	A crc32 collection/computation hash accumulator class
Cost::ChecksumDigest	A simple checksum digest function
Cost::MD5Digest	A md5 collection/computation accululator class
Cost::OZStream
Cost::SString
Cost::Slog	The slog class is used to stream messages to the system's logging facility (syslogd)
Cost::Pointer< T >	Used to create and manage referece counted pointers
Cost::Process	A class for containing portable process related functions that help create portable code
Cost::ReadLock	Used to protect a section of code through a ThreadLock for "read" access to the member function
Cost::RefObject	A reference countable object
Cost::RefPointer	Pointer to reference counted objects
Cost::TypeManager::Registration	This manages a registration to the typemanager - attempting to remove problems with the optimisers
Cost::Runable	A container for objects that can be queued against a runlist
Cost::Semaphore	A semaphore is generally used as a synchronization object between multiple threads or to protect a limited and finite resource such as a memory or thread pool
Cost::ThreadQueue	Somewhat generic queue processing class to establish a producer consumer queue
Cost::SemaphoreLock	Used to protect a section of code through a semaphore so that only x instances of the member function may execute concurrently
Cost::Serial	Used as the base for all serial I/O services under APE
Cost::SerialPort	The serial port is an internal class which is attached to and then serviced by a specified SerialService thread
Cost::TTYStream	TTY streams are used to represent serial connections that are fully "streamable" objects using C++ stream classes and friends
Cost::Socket	The Socket is used as the base for all Internet protocol services under Common C++
Cost::DCCPSocket	DCCP sockets are used for stream based connected sessions between two sockets
Cost::SimpleTCPStream	Simple TCP Stream, to be used with Common C++ Library
Cost::SocketPort	The socket port is an internal class which is attached to and then serviced by a specific SocketService "object"
Cost::TCPSocket	TCP sockets are used for stream based connected sessions between two sockets
Cost::TCPStream	TCP streams are used to represent TCP client connections to a server by TCP protocol servers for accepting client connections
Cost::TCPV6Socket	TCPV6 sockets are used for stream based connected sessions between two ipv6 sockets
Cost::UDPSocket	UDP sockets implement the TCP SOCK_DGRAM UDP protocol
Cost::UDPBroadcast	Representing a UDP socket used for subnet broadcasts, this class provides an alternate binding and setPeer() capability for UDP sockets
Cost::UDPReceive	Representing half of a two-way UDP connection, the UDP receiver can receive data from another peer host or subnet
Cost::UDPDuplex	UDP duplex connections impliment a bi-directional point-to-point UDP session between two peer hosts
Cost::UDPTransmit	Representing half of a two-way UDP connection, the UDP transmitter can broadcast data to another selected peer host or to an entire subnet
Cost::UDPDuplex	UDP duplex connections impliment a bi-directional point-to-point UDP session between two peer hosts
Cost::UnixSocket	Unix domain sockets are used for stream based connected sessions between processes on the same machine
Cost::UnixStream	Unix streams are used to represent Unix domain client connections to a local server for accepting client connections
Cstd::streambuf
Cost::Digest	The digest base class is used for implementing and deriving one way hashing functions
Cost::IZStream
Cost::OZStream
Cost::SString
Cost::Slog	The slog class is used to stream messages to the system's logging facility (syslogd)
Cost::TCPStream	TCP streams are used to represent TCP client connections to a server by TCP protocol servers for accepting client connections
Cost::TTYStream	TTY streams are used to represent serial connections that are fully "streamable" objects using C++ stream classes and friends
Cost::UnixStream	Unix streams are used to represent Unix domain client connections to a local server for accepting client connections
Cstreambuf
Cost::AppLog	Application logger is a class that implements a logger that can be used by applications to save log file somewhere on the system
Cost::String	This is a generic and portable string class
Cost::SString
Cstd::string_char_traits
Cost::cistring_char_traits< charT >
Cost::StringObject	Used to derive subclasses that use the String managed memory pool for all space allocations by overriding new and delete operators
Cost::StringTokenizer	Splits delimited string into tokens
Cost::SysTime	This class is used to access non-reentrant date and time functions in the standard C library
Cost::Thread	Every thread of execution in an application is created by instantiating an object of a class derived from the Thread class
Cost::PosixThread
Cost::SerialService	The SerialService is a thead service object that is meant to service attached serial ports
Cost::SocketService	The SocketService is a thread pool object that is meant to service attached socket ports
Cost::TCPSession	The TCP session is used to primarily to represent a client connection that can be managed on a seperate thread
Cost::TTYSession	The TTYSession aggragates a TTYStream and a Common C++ Thread which is assumed to be the execution context that will be used to perform actual I/O operations
Cost::ThreadQueue	Somewhat generic queue processing class to establish a producer consumer queue
Cost::UnixSession	The Unix domain session is used to primarily to represent a client connection that can be managed on a seperate thread
Cost::ThreadKey	This class allows the creation of a thread context unique "pointer" that can be set and retrieved and can be used to create thread specific data areas for implementing "thread safe" library routines
Cost::ThreadLock	Impliments a thread rwlock for optimal reader performance on systems which have rwlock support, and reverts to a simple mutex for those that do not
Cost::Time	Uses a integer representation of the current time
Cost::Datetime	Uses a julian date representation of the current year, month, and day and a integer representation of the current time
Cost::TimerPort	Timer ports are used to provide synchronized timing events when managed under a "service thread" such as SocketService
Cost::SerialPort	The serial port is an internal class which is attached to and then serviced by a specified SerialService thread
Cost::SocketPort	The socket port is an internal class which is attached to and then serviced by a specific SocketService "object"
Cost::TypeManager	This class manages the types for generation of the persistent objects
Cost::WriteLock	Used to protect a section of code through a ThreadLock for "write" access to the member function
Cost::XMLStream	This class impliments a basic XML stream parser that can be used to examine an XML resource thru virtual I/O methods
Cost::XMLRPC	This class impliments a core XMLRPC service without the underlying transports