Ocamlnet 3 Reference Manual

Ocamlnet consists of a number of libraries:

• netstring is about processing strings that occur in network context
• netcgi1 and netcgi2 focus on portable web applications
• nethttpd is a web server component (HTTP server implementation)
• netplex is a generic server framework
• rpc implements OncRPC
• netclient implements clients for HTTP, FTP, and Telnet
• equeue is an event queue used for many protocol implementations
• shell is about calling external commands
• netshm provides shared memory for IPC purposes
• netsys contains bindings for system functions
• smtp and pop are two further client implementations
• netmulticore and netcamlbox help parallelizing execution

A number of ideas and concepts are used throughout the libraries:

• Netchannels are a way to abstract sequential I/O channels
• The event queues provided by Equeue and Unixqueue make asynchronous protocol interpreters possible

Foreword

Some introductional notes how Ocamlnet is organized:

• Foreword

An overview of the list of changes is available in this external article:

• Ocamlnet 3 finally released

Platform support

Please read this document for extended information which features are supported on which platform:

• Platform: Which functions are available on which platform (POSIX/Win32). Also hints for portable programming.

External articles

• Stranger in a strange land, by Gerd Stolpmann. The Win32 port in Ocamlnet 3.

The netstring library

netstring focuses on string processing functions.

Netconversion	Conversion between character encodings
Netchannels	Object-oriented I/O: Basic types and classes
Netstream	A netstream is an input channel that is read block by block.
Mimestring	Low-level functions to parse and print mail and MIME messages
Netmime	Netmime contains high-level classes and functions to process mail and MIME messages.
Netsendmail	Functions to compose and send electronic mails
Neturl	Uniform Resource Locators (URLs)
Netaddress	Parsing of mail addresses
Netbuffer	A Netbuffer.t is a buffer that can grow and shrink dynamically.
Netpagebuffer	Buffer for page-aligned I/O
Netdate	Support for common date/time parsing and formatting.
Netencoding	Base64, Quoted Printable, URL encoding, HTML escaping
Netulex	Support module for Alain Frisch's ulex lexer generator
Netaccel	Accelerators for bytecode
Netaccel_link	Enables accelerator module Netaccel
Nethtml	Parsing of HTML
Nethttp	Basic definitions for the HTTP protocol
Netfs	Class type stream_fs for filesystems with stream access to files
Netglob	Globbing
Netauth	Some primitives for authentication
Netstring_str	Wrapper for regexps with Str syntax
Netstring_pcre	Wrapper for regexps with PCRE syntax
Netmappings	Internal access to the character conversion database
Netaux	Internal auxiliary functions
Netnumber	Binary encodings of numbers
Rtypes	Binary encodings of numbers (Legacy)
Xdr	External Data Representation
Xdr_mstring	Managed Strings

Guides

• Netchannels_tut: The Netchannels tutorial - strongly recommended read!
• Netmime_tut: The Netmime tutorial
• Netsendmail_tut: The Netsendmail tutorial
• Netulex_tut: The Netulex tutorial
• Neturl_tut: The Neturl tutorial

The netzip library

Support for (un)compressing data on the fly with object channels. Requires ocamlzip.

Netgzip

Gzip object channels

The netcgi1 library

The netcgi1 library is no longer supported in Ocamlnet 3. Please switch to netcgi2.

The netcgi2 library

This is the revised library for Web applications, now called netcgi2.

Netcgi	Common data-structures for CGI-like connectors.
Netcgi_common	Functions to develop new connectors.
Netcgi_cgi	Classical CGI connector.
Netcgi_fcgi	FastCGI connector.
Netcgi_ajp	Apache JServ Protocol (AJP) 1.3 connector.
Netcgi_scgi	SCGI connector.
Netcgi_test	Connector for testing your code.
Netcgi_dbi	Pools of connections for the ocamldbi generic database interface.
Netcgi1_compat	Compatibility module with the previous version of Netcgi.

Guides

• Netcgi_porting: Porting netcgi1 programs to netcgi2

The netcgi2-apache library

This is an Apache connector for the netcgi2 library.

Netcgi_apache	Netcgi Apache "mod" connector.
Netcgi_modtpl

The netcgi2-plex library

Netplex support for running Netcgi2 connectors:

Netcgi_plex

Netplex support for FastCGI, SCGI and AJP connectors

The nethttpd library

The nethttpd library is a Web server component written in O'Caml. For a full web server, you'll also need netplex.

Nethttpd_types	Type definitions for the HTTP daemon
Nethttpd_kernel	The protocol kernel of the HTTP daemon
Nethttpd_reactor	The reactive encapsulation of the HTTP daemon
Nethttpd_engine	The event-based encapsulation of the HTTP daemon
Nethttpd_services	Service Providers for HTTP daemon
Nethttpd_plex	Netplex support
Nethttpd_util	Utility functions

Guides

• Nethttpd_intro: Overview over the HTTP daemon

The netplex library

The netplex library is a protocol-independent server framework. Especially, it can be used in conjunction with nethttpd to build web servers, and with rpc to build RPC servers.

Netplex_types	Types for Netplex
Netplex_config	Read the configuration file
Netplex_controller	Controller
Netplex_container	Containers
Netplex_sockserv	Socket service creation
Netplex_workload	Workload management
Netplex_kit	Netplex toolkit
Netplex_cenv	Container environment
Netplex_log	Loggers
Netplex_main	Main program for Netplex servers
Netplex_mp	Multi-processing provider
Netplex_mt	Multi-threading provider
Netplex_mutex	Netplex-wide mutexes
Netplex_semaphore	Netplex-wide semaphores
Netplex_sharedvar	Netplex-wide variables
Netplex_encap	Type-safe marshalling between processes of the same executable
Rpc_netplex	Netplex support for RPC servers (TCP only)

Guides

• Netplex_intro: Introduction to Netplex
• Netplex_advanced: Advanced features of Netplex

External articles

• Parallelizing with Ocamlnet, by Gerd Stolpmann. Demonstrates how to parallelize matrix multiplications with Netplex-controlled worker processes.
• Mastering Multi-processing, by Gerd Stolpmann. About the new synchronization primitives in Ocamlnet 3

The rpc library

This library implements OncRPC (alias SunRPC).

Rpc	Common types and exceptions
Rpc_program	RPC programs
Rpc_client	RPC clients
Rpc_simple_client	Synchronous API for RPC clients
Rpc_proxy	RPC proxies
Rpc_server	RPC servers
Rpc_auth_sys	Authentication module AUTH_SYS
Rpc_portmapper	Portmapper version 2
Rpc_portmapper_aux
Rpc_portmapper_clnt
Rpc_transport	Low-level RPC transporters
Rpc_packer	The first n bytes of the packed value
Rpc_auth_gssapi	GSS-API for RPC authentication

Guides

• Rpc_intro: Introduction
• Rpc_mapping_ref: RPC Language Mapping Reference
• Rpc_intro_gss: Securing RPC with the GSS-API

External articles

• The next server, please!, by Gerd Stolpmann. About highly-available RPC.

The rpc-auth-local extension

Authentication for local socket connections.

Rpc_auth_local

Return the authentication method AUTH_LOCAL.

The rpc-auth-dh extension

This is Diffie-Hellman authentication for OncRPC (also known as "Secure RPC").

Rpc_auth_dh	Diffie-Hellman authentication (AUTH_DH alias AUTH_DES)
Rpc_key_service	Contact the keyserv daemon to encrypt/decrypt data with the common key.
Rpc_time	Get the time of the server (using the RFC 868 netdate protocol)

The rpc-xti extension

System V provides a network API called XTI in addition to the socket API. This library allows it to connect to RPC services that can only be reached over a local XTI connection ("cots" connection).

Rpc_xti_client

Minimal support for TI-RPC over the XTI API

The rpc_ssl extension

This library allows you to tunnel RPC through SSL/TLS.

Rpc_ssl

Securing RPC by SSL

The netgssapi library with the GSS-API framework

Netgssapi

GSS-API Definition

Security mechanisms

The netmech-scram library for SCRAM

Implements SCRAM (RFC 5802). Right now only for GSS-API.

Netmech_scram	SCRAM mechanism for authentication (RFC 5802)
Netmech_scram_gssapi	The SCRAM security mechanism for GSS-API

The netcamlbox library

Camlbox is a fast message-passing system between processes running on the same machine. It uses shared memory for communication. A message sent to a Camlbox is only copied once, not twice.

Netcamlbox

Camlboxes are a fast IPC mechanism to send Ocaml values from one process to another.

The netmulticore library

Netmulticore is an experimental framework for managing multiple processes, and sending messages between them.

Netmcore	Multi-processing for compute jobs
Netmcore_process	Statically typed processes
Netmcore_mempool	Memory pools
Netmcore_heap	Shared heaps of structured values
Netmcore_array	Shared arrays
Netmcore_buffer	Shared buffer
Netmcore_hashtbl	Shared hashtables
Netmcore_matrix	Shared 2-dimensional arrays (matrices)
Netmcore_queue	Shared queues
Netmcore_ref	Shared mutable variables
Netmcore_mutex	Mutexes
Netmcore_sem	Semaphores
Netmcore_condition	Condition variables
Netmcore_camlbox	Camlboxes for use in netmulticore programs

Guides

• Netmcore_tut: Tutorial

The netclient library

This library includes clients for HTTP, Telnet, and (incomplete) FTP.

Http_client	HTTP 1.1 client
Http_client_conncache	Connection cache
Http_fs	HTTP filesystem
Telnet_client	Telnet client
Ftp_client	FTP client
Ftp_data_endpoint	Senders and receivers for the FTP data connection

The equeue library

equeue is a fundamental library for event queues. It is mainly used by a number of other libraries of Ocamlnet to parallelize network code (so-called multiplexing).

Equeue	Equeue implements generic event queues.
Unixqueue	Unixqueues are one of the two forms of system event loops provided by Ocamlnet.
Unixqueue_pollset	Unixqueue implementation on top of Netsys_pollset
Unixqueue_select	This the old Unix.select-based imeplementation of event systems which was the default one until Ocamlnet-2.2.
Uq_engines	An engine performs a certain task in an autonomous way.
Uq_socks5	This module implements a SOCKS version 5 client (see RFC 1928) for use with the Uq_engines.connector, Uq_engines.listener, and Uq_engines.datagram_provider engine factories.
Uq_resolver	Support for pluggable resolvers
Uq_io	Unified engines for stream I/O

Guides

• Equeue_intro: Introduction to programming with equeue

External articles

• Equeue compared to Lwt, by Jake Donham.

The equeue-gtk1 and equeue-gtk2 extensions

Extensions for equeue to integrate the event queue into user interfaces made with lablgtk and lablgtk2

Uq_gtk

Integration with lablgtk/lablgtk2 event systems

The equeue-ssl extension

Extensions for equeue to support SSL

Uq_ssl

Asynchronous SSL connections

The equeue-tcl extension

Extension for equeue to integrate the event queue into user interfaces made with labltk

Uq_tcl

Integration with the labltk event system

The pop library

This is a simple POP 3 client.

Netpop

This is an interface for the Post Office Protocol - Version 3 (POP3) as specifed by RFC 1939.

The smtp library

This is a simple SMTP client.

Netsmtp

This is an interface for the Simple Mail Tranfer Protocol (SMTP) as specified by RFC 2821.

The shell library

The shell library allows you to start external commands. It is integrated into equeue.

Shell	Calls external programs, creates pipelines, etc.
Shell_sys	Calls external programs, creates pipelines, etc.
Shell_uq	Run shell commands within Unixqueues
Shell_fs	Shell filesystem

Guides

• Shell_intro: Motivation for shell

The netshm library

The netshm library manages a shared memory object either as hash table or array. It is designed to be used in multi-processing program architectures.

Netshm	Shared memory for O'Caml programs using multi-processing
Netshm_data	Data representation for shared memory
Netshm_hashtbl	Hash tables in shared memory
Netshm_array	Arrays in shared memory

Guides

• Netshm_intro: Shared Memory for IPC

The netsys library

The netsys library contains a number of low-level functions used by other Ocamlnet libraries.

Platform
Netexn	Exception registry
Netlog	Basic logging facility
Netsys	System calls missing in the Unix module
Netsys_posix	POSIX-specific system calls missing in the Unix module
Netsys_oothr	Object-oriented thread API
Netsys_signal	Signal handler framework
Netsys_tmp	Temporary files
Netsys_mem	Bigarrays as memory buffers
Netsys_pollset	Sets of file descriptors for polling
Netsys_pollset_generic	Returns a good standard implementation of pollset for this platform.
Netsys_pollset_posix	Pollsets for POSIX operating systems
Netsys_pollset_win32	Pollsets for Win32
Netsys_win32	Primitives for Win32
Netsys_rng	Random-number generator

Index

Index of types
Index of exceptions
Index of values
Index of class attributes
Index of class methods
Index of classes
Index of class types
Index of modules
Index of module types

Authors

The Ocamlnet libraries have been initially written by Gerd Stolpmann and Patrick Doane.

Contributions by

• Nicolas George: Netdate
• Eric Stokes: FastCGI support
• Pierre Habouzit: SMTP client
• Christophe Troestler: Revised version of netcgi
• Deokhwan Kim: Support for EUC-KR

Sponsorships by

• Baretta s.r.l: Nethttpd
• California State University: SSL support for RPC, Netplex

This web site is published by Informatikbüro Gerd Stolpmann