Index of types

The service is protected by the access control rule

Access control by host: `Allow: Only the listed hosts are allowed; all other are denied, `Deny: The listed hosts are denied; all other are allowed

`Callback is used for normal handlers, and `Install for exclusive handlers.

The pair local_part@domain as O'Caml type.

See config

This is the type of functions arg_store so that arg_store env name header tells whether to `Discard the argument or to store it into a `File or in `Memory.

See Netcgi.arg_store.

An assignment redirects file descriptors while calling a process

A bad request is a violation where the current request cannot be decoded, and it is not possible to accept further requests over the current connection.

This is only a small subset of the HTTP 1.1 cache control features, but they are usually sufficient, and they work for HTTP/1.0 as well.

See Netcgi.cache_control.

The cache control token for the Cache-control header

A camlbox may receive messages

The address of a camlbox is a string that does not contain slashes.

An endpoint that may send messages to a camlbox

How many connections a container can accept in addition to the existing connections: `Normal_quality n: It can accept n connections with normal service quality, n > 0, `Low_quality n: It can accept n connections with low service quality (e.g. because it is already quite loaded), n > 0, `Unavailable: No capacity free

Now simply called Netcgi.config.

A charset is simply a set of code points.

Whether a close_out implies a commit or rollback operation

An FTP command.

The command state: `Init: Just connected, no greeting message arrived yet, `Success: Got the greeting message/last command was successful, `Proto_error: currently unused, `Temp_failure: Last command was not successful, and the code was between 400 and 499, `Perm_failure: Last command was not successful, and the code was between 500 and 599, `Rename_seq: Used instead of `Success after the RNFR command, `Restart_seq: Used instead of `Success after the REST command, `User_pass_seq: Used instead of `Success after the USER command when a password must be typed in, `User_acct_seq: Used instead of `Success after the USER command when an account ID must be typed in, `Pass_acct_seq: Used instead of `Success after the PASS command when an account iD must be typed in, `Preliminary: a reply with code 100 to 199. There will be another final reply for the command

A command describes how to start a new process

The read-only view of a complex_mime_message

See Netcgi.config.

Three type abbreviations for logging functions

Specifies the service to connect to:

This type corresponds with Uq_engines.connect_address: An engine connecting with an address `X will return a status of `X.

Directive how to go on with the current connection: `Conn_close: Just shut down and close descriptor, `Conn_close_linger: Linger, shut down, and close descriptor, `Conn_keep_alive: Check for another request on the same connection, `Conn_error e: Shut down and close descriptor, and handle the exception e

identifies the connection of a session.

Same as Rpc_key_service.connector

How to connect to keyserv: `Direct(c,p): Create a direct RPC connection to the keyserv program listening at c using protocol p. This usually only works if c is a local transport like Unix Domain., `Keyenvoy path: Call the keyenvoy program installed at path

A consumer receives data from a called process

Such objects identify containers.

The container state for workload management: `Accepting(n,t): The container is accepting further connections. It currently processes n connections. The last connection was accepted at time t (seconds since the epoch)., `Busy: The container does not accept connections, `Starting t: The container was started at time t and is not yet ready., `Shutting_down: The container is being shutted down.

Compatibility name.

Specifies the task the copier class has to do:

A cursor denotes a character position in an encoded string

A data_chunk is a substring of a string.

The data manager consists of several manager functions.

- `Unix_dgram: Datagrams over Unix domain sockets `Inet_udp: Internet v4 UDP protocol, `Inet6_udp: Internet v6 UDP protocol

Describes the state of the socket used for data transfers.

Debug logger: The first string is the module name, and the second is the message

The type document represents parsed HTML documents:

The domain of the mailbox

Element classes are a property used in the HTML DTD.

An encapsulated value with a type identifier

The polymorphic variant enumerating the supported encodings.

The type of states with result values of type 't: `Working n: The engine is working. The number n counts the number of events that have been processed., `Done arg: The engine has completed its task without errors. The argument arg is the result value of the engine, `Error exn: The engine has aborted because of an error. The argument exn describes the error as an exception., `Aborted: The engine has aborted because the abort method was called

The abstract type of a process environment

Entity tags can be weak or strong

An event is triggered when the condition of an operation becomes true, when a signal happens, or when the event is (artificially) added to the event queue (add_event, below).

A function of type exn_handler allows to define a custom handler of uncaught exceptions raised by the unit -> unit parameter.

Possible addresses: `Socket s: The socket at this socket address, `Socket_file f: The file f contains the (anonymous) port number of a socket bound to 127.0.0.1 (This is meant as substitute for Unix Domain sockets on Win32.), `W32_pipe name: The Win32 pipe with this name which must be of the form "\\.\pipe\<pname>", `W32_pipe_file f: The file f contains the (random) name of a Win32 pipe, `Container(socket_dir,service_name,proto_name,thread_id): The special endpoint of the container for service_name that is running as thread_id. It is system-dependent what this endpoint "is" in reality, usually a socket or named pipe. If any container of a service is meant, the value `Any is substituted as a placeholder for a not yet known thread_id.

These are the serious protocol violations after that the daemon stops any further processing.

Some information what kind of operations are reasonable for descriptors: `Read_write: The descriptor is neither a socket not one of the other special cases, so only read/write is possible if read/write is possible at all. This style is also used if it is meaningless to use data I/O like read/write at all., `Recv_send(sockaddr,peeraddr): The descriptor is a connected socket. recv/send are the preferred operations., `Recvfrom_sendto: The descriptor is an unconnected socket, and it is possible to ask for addresses when exchanging data, so recvfrom/sendto are the preferred operations., `Recv_send_implied: The descriptor is a socket with implied connection. There are no socket addresses. recv/send are the preferred operations. It is not possible to call getsockname or getpeername., `W32_pipe: The descriptor is a proxy descriptor for a Win32 named pipe as returned by Netsys_win32.pipe_descr. , `W32_pipe_server: The descriptor is a proxy descriptor for a Win32 pipe server as returned by Netsys_win32.pipe_server_descr. , `W32_event: The descriptor is a Win32 proxy descriptor for an event as returned by Netsys_win32.create_event. It is not possible to read/write with these descriptors., `W32_process: The descriptor is a proxy descriptor for a Win32 process as returned by Netsys_win32.create_process. It is not possible to read/write with these descriptors., `W32_input_thread: The descriptor is a proxy descriptor for a Win32-specific input thread as returned by Netsys_win32.create_input_thread. , `W32_output_thread: The descriptor is a proxy descriptor for a Win32-specific output thread as returned by Netsys_win32.create_output_thread. Win32: For the exact meaning of proxy descriptors, please see Netsys_win32.

Add-on features for file services: `Enable_gzip: If enabled, files ending in .gz are assumed to be in gzip compression. When there is both the base file and the gzip file ending in .gz, accesses to the base file (!) are transmitted with gzip compression., `Enable_index_file: If enabled, accesses to directories are redirected to index files. The possible file names are given in the string list. E.g. `Enable_index_file ["index.html"; "index.htm"]. It is redirected to these files, so these can be handled by different services if neccessary., `Enable_listings: If enabled, directory listings are generated by calling the argument function. The PATH_TRANSLATED property of the environment contains the absolute name of the directory to list. The PATH_INFO property is the corresponding URI path. SCRIPT_NAME is meaningless.

Describes a file service

There are several methods how to specify filenames: `NVFS name: The "Network Virtual File System" is the normal way of accessing FTP files. The client walks into the directory containing the file using CWD and CDUP commands, and calls the file operation from this directory. For simplicity, this client interprets slashes in name as path component separators. The FTP server will never see these slashes., `Verbatim name: The string name is passed to the server without transforming it in any way. In the future, there will be a third way of referring to files: TVFS, the "Trivial Virtual File System".

Same as engine_state without `Working.

The form_code has a meaning when FTP is used to print files: `Non_print: This is not the case., `Telnet: Telnet control codes are used for vertical movement, `ASA: ASA (Fortran) control codes are used for vertical movement

single precision float

double precision float

Tokens generated by http_response: `Resp_wire_data are data tokens., `Resp_end indicates the end of the response.

The ftp_state reflects the knowledge of the client about what has been agreed upon with the server.

Determines whether and how keyboard signals (SIGINT, SIGQUIT) are forwarded from the caller to the new child.

A group is an abstract tag for a set of events, resources, and event handlers.

Determines in which process group the new process will run

Specifies how the job instance is related to process groups

The `Base header is set by the user of http_call and is never changed during processing the call.

For name- and IP-based virtual hosting this record describes the individual host.

Describes virtual hosting by pairs (host,service): If host matches the incoming request, the corresponding service is performed to generate the response.

How to deal with automatic reconnections, especially when the connection crashes.

Method name, URI

Options for the whole pipeline

Indicates the immediate reaction upon an arriving HTTP header: `Accept_body is the regular way of processing requests. If necessary, the client is told to continue sending the rest of the request., `Reject_body can be used when the body of the request is not needed, and the response will be negative., `Static means to send the header and a constant string back as response. The header is taken from the environment if not explicitly passed, Note: The Content-Length header is automatically added. The Content-Type defaults to "text/html"., `File is similar to this, but the data come from a file. The file is specified by an absolute pathname. The range of the file is given by the start position and the length of the range. The header is taken from the environment if not explicitly passed, Note: The Content-Length header is automatically added. The Content-Type defaults to "text/html"., `Std_response is similar to `Static, however the body is the standard text for the status code. If the header is omitted, it is taken as empty. The third argument is an optional entry into the error log. Note: The Content-Length header is automatically added. The Content-Type defaults to "text/html".

HTTP response status:

The type of the nethttpd_processor function

Specifies the user: `Effective_user: Take the effective user of the process, `Real_user: Take the real user of the process, `This_user(uid,gid,sup_groups,hostname): Pretend to be this user

Devices with look-ahead

Currently supported devices for input: `Polldescr(st,fd,esys): The poll system call is used with file descriptor fd to wait for incoming data. The event system esys is the underlying event queue. This works well for pipes, sockets etc. but not for normal files. The style st can be obtained from fd via Netsys.get_fd_style., `Multiplex mplex: The multiplex controller mplex is used as device. , `Buffer buf: Data comes from the buffer buf (which in turn is connected with a second device)

This is not used anywhere.

This type is for the method enhanced_input of enhanced_raw_in_channel.

This is not the business of the user.

32 bit signed integer

64 bit signed integer

Indicates the status of the job

The log levels (syslog-like)

Log levels, modeled after syslog

Services are selected by calling the selector function.

Specifies the resource to listen on:

Usually the user name

The local_receiver is the object that gets the data received over the data connection.

The local_sender is the object that provides the data sent over the data connection.

The locking method is used to ensure that parallel read and write operations to the memory object do not interfer with each other.

A logging function takes a level, and the message

A managed client

We consider 1-dimensional bigarrays of chars as memory buffers.

We consider 1-dimensional bigarrays of chars as memory buffers.

A pool of memory blocks that are all the same size and page-aligned (if the OS supports this).

The first service is selected for which the method filter accepts the request

The request is only accepted if listed (for `Limit), or if not listed (for `Limit_except).

Simple MIME message, in a form that is compatible with complex ones.

Read-only variant of simple messages

The opaque type of a scanner for structured values

Determines the type of the server for create2:

Determines the type of the client for create2:

Model constraints define the possible sub elements of an element: `Inline: The sub elements must belong to the class `Inline, `Block: The sub elements must be members of the classes `Block or `Essential_block, `Flow: The sub elements must belong to the classes `Inline, `Block, or `Essential_block, `Empty: There are no sub elements, `Any: Any sub element is allowed, `Special: The element has special content (e.g. <script>). Functionally equivalent to `Empty, `Elements l: Only these enumerated elements may occur as sub elements, `Or(m1,m2): One of the constraints m1 or m2 must hold, `Except(m1,m2): The constraint m1 must hold, and m2 must not hold, `Sub_exclusions(l,m): The constraint m must hold; furthermore, the elements enumerated in list l are not allowed as direct or indirect subelements, even if m or the model of a subelement would allow them. The difference to `Except(m, `Elements l) is that the exclusion is inherited to the subelements. The `Sub_exclusions expression must be toplevel, i.e. it must not occur within an `Or, `Except, or another 'Sub_exclusions expression. Note that the members of the class `Everywhere are allowed everywhere, regardless of whether the model constraint allows them or not.

a managed set

Sets in which order managed clients are picked from the services array passed to create_mset: `Failover: Picks an element from the first service in services that is enabled and has free capacity. That means that the first service is preferred until it is maxed out or it fails, then the second service is preferred, and so on., `Balance_load: Picks an element from the service in services that is enabled and has the lowest load.

How to parse multipart messages: `None: Do not handle multipart messages specially. Multipart bodies are not further decoded, and returned as `Body b where b is the transfer-encoded text representation., `Flat: If the top-level message is a multipart message, the parts are separated and returned as list. If the parts are again multipart messages, these inner multipart messages are not furher decoded and returned as `Body b., `Deep: Multipart messages are recursively decoded and returned as tree structure. This value determines how far the complex_mime_message structure is created for a parsed MIME message.

These are old-style cookies, as introduced by Netscape.

See class input_async_mplex for explanations

See class output_async_mplex for explanations

An operation specifies the condition to wait for.

Determines how an URL part is generated: `Env: Take the value from the environment., `This v: Use this value v. It must already be URL-encoded., `None: Do not include this part into the URL.

See Netcgi.other_url_spec.

Buffers that can be attached to a device to get buffered I/O

Currently supported devices for output: `Polldescr(fd,esys): The poll system call is used with file descriptor fd to wait until data can be output. The event system esys is the underlying event queue. This works well for pipes, sockets etc. but not for normal files., `Multiplex mplex: The multiplex controller mplex is used as device. , `Buffer buf: Data is written to the buffer buf (which in turn is connected with a second device)

This is not used anywhere.

This is not the business of the user.

The ouput type determines how generated data is buffered.

See Netcgi.output_type.

Type of parallelization: `Multi_processing on a single host, `Multi_threading on a single host, `Controller_attached means that the service runs within the controller. This is (for now) only allowed for controller-internal services.

Poll events.

The array of poll_cell entries

The poll cell refers to the descriptor poll_fd.

The port of the data connection: `Active means that the server initiates the data connection to the listening client, and in the case of `Passive the client initiates the data connection to the listening server.

The private part of the http_call class type

A process is the running instance of a command (a Unix process)

A producer generates data sent to a called process

The base protocol.

Determines how the query part of URLs is generated: `Env: The query string of the current request., `This l: The query string is created from the specified argument list l., `None: The query string is omitted., `Args: deprecated, use `This (left for backward compatibility).

See Netcgi.query_string_spec.

result type

result type

The cache

How failures of individual ports are interpreted: `Independent: When a connection to a remote port repeatedly fails, only this port is disabled, `Failing_port_disables_host p: When a connection to the TCP port p repeatedly fails, the whole remote host is disabled. Other ports do not disable the host, but are treated as in `Independent., `Any_failing_port_disables_host: When a connection to any TCP port repeatedly fails, the whole remote host is disabled, `None: Nothing is disabled Note that the rcache_availability hook is not affected by the policy; this hook is called anyway.

Policy to apply by setup_client_block if the request message indicates a body.

The type of regular expressions; now based on Pcre

The type of regular expressions; now based on Pcre

Reply code plus text

The representation of the transferred file: `ASCII: An ASCII variant is used, i.e. the server sends files in ASCII encoding with CR/LF as end-of-line marker. Supported by all servers., `EBCDIC: An EBCDIC variant is used, i.e. the server sends files in EBCDIC encoding with NEL as end-of-line marker, `Image: The file is transferred in its original binary representation. Supported by all servers. "Local" representations are not supported.

Embedded in the single place of use.

A req_token represents a textual part of the received request: `Req_header is the full received header. Together with the header, the corresponding http_response object is returned which must be used to transmit the response., `Req_expect_100_continue is generated when the client expects that the server sends a "100 Continue" response (or a final status code) now. One should add `Resp_info_line resp_100_continue to the send queue if the header is acceptable, or otherwise generate an error response. In any case, the rest of the request must be read until `Req_end., `Req_body is a part of the request body. The transfer-coding, if any, is already decoded., `Req_trailer is the received trailer, `Req_end indicates the end of the request (the next request may begin immediately)., `Eof indicates the end of the stream, `Bad_request_error indicates that the request violated the HTTP protocol in a serious way and cannot be decoded. It is required to send a "400 Bad Request" response. The following token will be `Eof., `Fatal_error indicates that the connection crashed. The following token will be `Eof., `Timeout means that nothing has been received for a certain amount of time, and the protocol is in a state that the next request can begin. The following token will be `Eof. Note that it is always allowed to send tokens to the client.

The method (including the URI), and the HTTP version

A name resolver is a function r called as r esys name reply.

The response state: `Inhibited = it is not yet allowed to start the response, `Queued = the response waits on the queue for activation, `Active = the response is currently being transmitted, `Processed = the response has been completely sent, `Error = an error occurred during the transmission of this response, `Dropped = an earlier response forced to close the connection, and this response is dequeued

The resp_token represents a textual part of the response to send: `Resp_info_line is an informational status line (code=100..199). There can be several informational lines, and they can be accompanied with their own headers. Such lines are only sent to HTTP/1.1 clients., `Resp_status_line is the final status line to send (code >= 200), `Resp_header is the whole response header to send, `Resp_body is the next part of the response body to send., `Resp_trailer is the whole response trailer to send (currently ignored), `Resp_action is special because it does not directly represent a token to send. The argument is a function which is called when the token is the next token on the active event queue. The function is also called when the event queue is dropped because of an error (the state of the response object indicates this). The function must not raise exceptions except Unix_error, and it must not block.

How to create the response body: `Memory: The response body is in-memory, `File f: The response body is stored into the file whose name is returned by f(), `Body f: The response body is stored into the object returned by f()

The type of matching results

The type of matching results

argument type

argument type

An opaque type containing the information of s_token plus: where the token occurs, RFC-2047 access functions

The type of encoded parameters (RFC 2231)

A token may be one of: QString s: The quoted string s, i.e a string between double quotes. Quoted pairs are already decoded in s., Control c: The control character c (0-31, 127, 128-255), Special c: The special character c, i.e. a character from the specials list, DomainLiteral s: The bracketed string s, i.e. a string between brackets. Quoted pairs are already decoded in s., Comment: A string between parentheses. This kind of token is only generated when the option Return_comments is in effect., EncodedWord((charset,lang),encoding,encoded_word): An RFC-2047 style encoded word: charset is the name of the character set; lang is the language specifier (from RFC 2231) or ""; encoding is either "Q" or "B"; and encoded_word is the word encoded in charset and encoding. This kind of token is only generated when the option Recognize_encoded_words is in effect (if not, Atom is generated instead)., Atom s: A string which is neither quoted not bracketed nor written in RFC 2047 notation, and which is not a control or special character, i.e. the "rest", End: The end of the string

A serial number for the optional tracking of ownership

The service factory function is called when a service configuration section of a certain type needs to be read.

identifies a pair of a call and a reply

A shared memory descriptor refers to a shared memory object.

A shm_name is a name for a shared memory object.

A simplified_dtd is an associative list of tuples (element_name, (element_class, constraint)): For every element_name it is declared that it is a member of element_class, and that the sub elements must satisfy constraint.

The state of a socket: `Enabled: The controller allows containers to accept connections. Note that this does not necessarily means that there such containers., `Disabled: It is not allowed to accept new connections. The socket is kept open, however., `Restarting b: The containers are being restarted. The boolean argument says whether the socket will be enabled after that., `Down: The socket is down/closed

Extended names for socket addresses.

The state: `Down: The initial state, and also reached after a socket error, or after one of the shutdown functions is called. Although `Down, there might still some cleanup to do. When RPC functions are called, the client is automatically revived., `Connecting: This state is used while the initial ping is done. It does not reflect whether the client is really TCP-connected. Without initial ping, this state cannot occur., `Up s: The client is (so far known) up and can be used. s is the socket address of the local socket

Condensed status information of a HTTP call: `Unserved: The call has not yet been finished, `HTTP_protocol_error e: An error on HTTP level occurred. Corresponds to the exception Http_protocol., `Successful: The call is successful, and the response code is between 200 and 299., `Redirection: The call is successful, and the response code is between 300 and 399., `Client_error: The call failed with a response code between 400 and 499., `Server_error: The call failed for any other reason.

= (code, phrase)

The way the Netcgi_types.cgi_activation object is created.

These are options for `Std_activation.

Specifies where to store the body of a mail message.

Embedded in the single place of use.

The user can pass data buffers that base either on strings or on bigarrays of char (memory).

The client supports two structures: `File_structure: Files are simply contiguous streams of bytes, `Record_structure: Files are sequences of records. FTP does not make a difference between variable and fixed length records. It is not forbidden that the records are themselves structured into lines, in fact it can happen that end-of-line markers are contained in binary records. Operating systems that support record-structured files often store text files in this format, i.e. every line is stored in its own record, without end-of-line marker. If record structure is selected by a STRU command, it is recommended to use the classes Ftp_data_endpoint.out_record_channel and Ftp_data_endpoint.in_record_channel for the local representation of the files, otherwise the records may be incorrectly mapped to the local conventions. Page-structured files (i.e.

This type determines whether to keep requests and responses synchronized or not.

The facilities.

The syslog options: `Cons: Fall back to console logging if syslog is unavailable, `Ndelay: Open the connection immediately, `Odelay: Open the connection at the first call syslog (default), `Nowait: Do not wait until it is ensured that the message is sent, `Pid: Log the PID with every message

represents a server for an RPC program

represents a client for the portmapper

The type of simple clients

The client type

The type of RPC clients

Type of RPC programs

represents a client of the keyserv daemon

Functions to manipulate cookies.

The union of mailbox and group

Mutable cookie type.

The type of handler functions.

Apache request_rec structure.

Apache conn_rec structure.

Apache server_rec structure.

Apache table structure.

This is the type of an event system with events of type 'a

A telnet_command is the interpretation of the octets in a Telnet session, i.e.

Connectors: Telnet_connect(host,port): The client connects to this port., Telnet_socket s: The client uses an already connected socket. Why Telnet_socket? Telnet is a symmetrical protocol; client and servers implement the same protocol features (the only difference is the environment: a client is typically connected with a real terminal; a server is connected with a pseudo terminal).

telnet_negotiated_option: names for the most common options, and the generic name Telnet_option for other options.

An option has one of three states: Not_negotiated: There was no negotiation about the option. This means that the option is turned off (but this client is allowed to reject it explicitly), Accepted: Both sides have accepted the option., Rejected: One side has rejected the option. This also means that the option is off, but the client refuses to send further acknoledgements that the option is off (to avoid endless negotiation loops).

telnet_options: modifies the behaviour of the client.

Possible representation of text data: `ASCII means an ASCII-compatible encoding where the newline character is represented by CR/LF.

A system-specific identifier of the thread/process

A timer

The transmission mode selects how the data are encoded in the data connection.

The transmission mode as described in RFC 959.

32 bit unsigned integer

64 bit unsigned integer

Describes that services are bound to URI prefixes.

Values of type url describe concrete URLs.

Values of type url_syntax describe which components of an URL are recognized, which are allowed (and optional), and which are required.

How Rpc_server.get_user returns the user as string: `Full: The format includes all transmitted details: "<uid>.<gid>.<gid1>.<gid2>...@<hostname>". All user and group IDs are numeric. The first two numbers, <uid> and <gid> are always present. The other numbers are the supplementary group IDs and can be omitted. The <hostname> is the name passed in the credentials., `UID: The string is the numeric user ID, `Custom f: The string is returned by the function f. The arguments are uid, gid, the array of the supplementary group IDs and the hostname.

How verbose the RPC ftrace is: `Name_only: For each RPC call only the name is logged, `Name_abbrev_args: The name and the abbreviated argument list are logged, `Name_full_args: The name and the full argument list are logged

See the msdn docs for GetConsoleMode for details

A pipe endpoint

A pipe server.

A handle to spawned processes

A wait identifier is used to distinguish between several timers, see type operation.

The Work_around_ part has been dropped as it is clear at the spot of use.

This is the validated version of xdr_type_term.

A validated type system.

Bind names to types.