This section lists and describes the C++ classes found in the Communications <ToolKits>. Trivial classes and helper classes are not listed. The prefix os_ is used by most classes to avoid name conflicts with other vendors' class names and differentiates them from ANSI/ISO classes.

IO<ToolKit> Classes

`os_adapter`	a smart-pointer mechanism used to manage universal device adapters.
`os_buffer`	an efficient, auto-grow, memory buffer.
`os_buffer_device`	an interface for memory buffers (`os_buffer`).
`os_cache`	a specialized device that provides efficient, buffered I/O for all `os_adapter`-supported devices. This class can be used to improve the performance of slow or non-buffered devices. By chaining an `os_cache` into the stream, users can control the buffering policies independent of the device.
`os_cache_device`	an interface for caches (`os_cache`).
`os_device`	a generic device interface that supports a wide variety of communication mechanisms, including files, sockets, and named pipes. Designed for easy adaptation to your industry-specific devices.
`os_io_control`	manipulates values commonly used in the creation and use of I/O objects.
`os_io_status`	obtains and manages the status of I/O objects.
`os_io_toolkit`	provides automatic initialization of IO<ToolKit>.
`os_io_toolkit_error`	represents an error condition in IO<ToolKit>.
`os_open_control`	manipulates values commonly used in the creation of I/O objects.

Streaming<ToolKit> Classes

`os_ascii`	ASCII Data Representation protocol that provides a readable data stream useful for debugging and performance tuning.
`os_bstream`	the Universal Stream Service (USS) interface that provides portable, non-intrusive object transport and persistence. Works with all `os_adapter`-supported devices and protocols that use the `os_protocol` interface.
`os_fstream_device`	an interface for ANSI/ISO `fstream`.
`os_iostream_device`	an interface for generic ANSI/ISO `iostream`.
`os_istream_device`	an interface for generic ANSI/ISO `istream`.
`os_itstream`	provides an ANSI/ISO input stream (`istream`) for all `os_adapter`-supported devices.
`os_ndr`	an implementation of the industry-standard Network Data Representation (NDR) protocol.
`os_ostream_device`	interface for generic ANSI/ISO `ostream`.
`os_otstream`	provides an ANSI/ISO output stream (`ostream`) for all `os_adapter`-supported devices.
`os_protocol`	a base class that defines communication protocol interfaces. Designed to be extensible. Developers can easily add support for new protocols.
`os_streaming_toolkit`	provides automatic initialization of Streaming<ToolKit>.
`os_streaming_toolkit_error`	represents an error condition in Streaming<ToolKit>.
`os_tstream`	an ANSI/ISO IOStream interface for all `os_adapter`-supported devices. Provides text streaming capabilities to sockets, named pipes, and other unconventional communication mechanisms.

File<ToolKit> Classes

`os_directory`	a directory or folder in a file system.
`os_file`	a portable file.
`os_file_device`	a generic interface for `os_file` to use with `os_adapter`.
`os_file_lock`	a lock for all or part of a file; protects files from concurrent access.
`os_file_system`	a file system that stores files and directories.
`os_file_toolkit`	provides automatic initialization of File<ToolKit>.
`os_file_toolkit_error`	represents an error condition in File<ToolKit>.
`os_path`	a file name, file path, or directory path with abstractions required for portability between operating systems and for simple path manipulation.

Pipe<ToolKit> Classes

`os_pipe`	a portable pipe providing reliable, connection-oriented, point-to-point communication.
`os_pipe_connection_server`	accepts incoming requests for pipe connections.
`os_pipe_device`	a generic interface for `os_pipe` to use with `os_adapter`.
`os_pipe_toolkit`	provides automatic initialization of Pipe<ToolKit>.
`os_pipe_toolkit_error`	represents an error condition in Pipe<ToolKit>.

Network<ToolKit> Classes

`os_host`	represents an Internet host.
`os_ip_address`	represents and manipulates an Internet protocol (IP) address.
`os_service`	represents an Internet service.
`os_socket_address`	represents and manipulates a socket address.
`os_tcp_connection_server`	accepts incoming requests for TCP socket connections.
`os_tcp_socket`	a TCP socket, or stream socket, that provides reliable, connection-oriented, point-to-point communication between a server socket and a client socket.
`os_udp_socket`	a UDP socket (also called a datagram socket). A datagram is a single packet of information sent from one socket to another. The sender socket must know the address of the destination socket. Datagram sockets provide unreliable, connectionless communication.
`os_io_multiplexer`	monitors a set of I/O descriptors for pending operations.
`os_tcp_socket_device`	a generic interface for `os_tcp_socket` to use with `os_adapter`.
`os_network_toolkit`	provides automatic initialization of Network<ToolKit>.
`os_network_toolkit_error`	represents an error condition in Network<ToolKit>.

Framework<ToolKit> Classes

`os_singleton`	templatized Singleton pattern that adorns other objects, without requiring modification to the original class.
`os_observable`	templatized Observer pattern that adorns other objects, without requiring modification to the original class.
`os_handler_stream`	provides a TCP socket stream.
`os_same_thread_executor`	provides a same thread execution concurrency strategy.
`os_new_thread_executor`	provides a new thread execution concurrency strategy.
`os_thread_pool_executor`	provides a thread pool execution concurrency strategy.
`os_creator`	creates a new object on the heap and returns it.
`os_tcp_acceptor`	accepts requests for TCP socket connections and initiate service handlers.
`os_tcp_connector`	provides connection initiation and service handler execution.
`os_dispatcher`	provides I/O event dispatching.
`os_framework_toolkit`	provides automatic initialization of Framework<ToolKit>.
`os_framework_toolkit_error`	represents an error condition in Framework<ToolKit>.

`os_group`	represents a group.
`os_security_toolkit`	provides automatic initialization of Security<ToolKit>.
`os_security_toolkit_error`	represents an error condition in Security<ToolKit>.
`os_user`	represents a user.