/// <reference types="node" />
export { capability, context, curveKeyPair, version, Context, Event, EventOfType, EventType, Socket, Observer, Proxy, } from "./native";
import { Context, EventOfType, EventType, Options, Socket } from "./native";
/**
 * A type representing the messages that are returned inside promises by
 * {@link Readable.receive}().
 */
export type Message = Buffer;
/**
 * Union type representing all message types that are accepted by
 * {@link Writable.send}().
 */
export type MessageLike = ArrayBufferView | ArrayBuffer | SharedArrayBuffer | string | null;
/**
 * Describes sockets that can send messages.
 *
 * @typeparam M The type of the message or message parts that can be sent.
 * @typeparam O Rest type for any options, if applicable to the socket type
 * (DRAFT only).
 */
export interface Writable<M extends MessageLike | MessageLike[] = MessageLike | MessageLike[], O extends [...object[]] = []> {
    /**
     * ZMQ_MULTICAST_HOPS
     *
     * Sets the time-to-live field in every multicast packet sent from this
     * socket. The default is 1 which means that the multicast packets don't leave
     * the local network.
     */
    multicastHops: number;
    /**
     * ZMQ_SNDBUF
     *
     * Underlying kernel transmit buffer size in bytes. A value of -1 means leave
     * the OS default unchanged.
     */
    sendBufferSize: number;
    /**
     * ZMQ_SNDHWM
     *
     * The high water mark is a hard limit on the maximum number of outgoing
     * messages ØMQ shall queue in memory for any single peer that the specified
     * socket is communicating with. A value of zero means no limit.
     *
     * If this limit has been reached the socket shall enter an exceptional state
     * and depending on the socket type, ØMQ shall take appropriate action such as
     * blocking or dropping sent messages.
     */
    sendHighWaterMark: number;
    /**
     * ZMQ_SNDTIMEO
     *
     * Sets the timeout for sending messages on the socket. If the value is 0,
     * {@link send}() will return a rejected promise immediately if the message
     * cannot be sent. If the value is -1, it will wait asynchronously until the
     * message is sent. For all other values, it will try to send the message for
     * that amount of time before rejecting.
     */
    sendTimeout: number;
    /**
     * Sends a single message or a multipart message on the socket. Queues the
     * message immediately if possible, and returns a resolved promise. If the
     * message cannot be queued because the high water mark has been reached, it
     * will wait asynchronously. The promise will be resolved when the message was
     * queued successfully.
     *
     * ```typescript
     * await socket.send("hello world")
     * await socket.send(["hello", "world"])
     * ```
     *
     * Queueing may fail eventually if the socket has been configured with a
     * {@link sendTimeout}.
     *
     * A call to {@link send}() is guaranteed to return with a resolved promise
     * immediately if the message could be queued directly.
     *
     * Only **one** asynchronously blocking call to {@link send}() may be executed
     * simultaneously. If you call {@link send}() again on a socket that is in the
     * mute state it will return a rejected promise with an `EBUSY` error.
     *
     * The reason for disallowing multiple {@link send}() calls simultaneously is
     * that it could create an implicit queue of unsendable outgoing messages.
     * This would circumvent the socket's {@link sendHighWaterMark}. Such an
     * implementation could even exhaust all system memory and cause the Node.js
     * process to abort.
     *
     * For most application you should not notice this implementation detail. Only
     * in rare occasions will a call to {@link send}() that does not resolve
     * immediately be undesired. Here are some common scenarios:
     *
     * * If you wish to **send a message**, use `await send(...)`. ZeroMQ socket
     *   types have been carefully designed to give you the correct blocking
     *   behaviour on the chosen socket type in almost all cases:
     *
     *   * If sending is not possible, it is often better to wait than to continue
     *     as if nothing happened. For example, on a {@link Request} socket, you
     *     can only receive a reply once a message has been sent; so waiting until
     *     a message could be queued before continuing with the rest of the
     *     program (likely to read from the socket) is required.
     *
     *   * Certain socket types (such as {@link Router}) will always allow
     *     queueing messages and `await send(...)` won't delay any code that comes
     *     after. This makes sense for routers, since typically you don't want a
     *     single send operation to stop the handling of other incoming or
     *     outgoing messages.
     *
     * * If you wish to send on an occasionally **blocking** socket (for example
     *   on a {@link Router} with the {@link Router.mandatory} option set, or on a
     *   {@link Dealer}) and you're 100% certain that **dropping a message is
     *   better than blocking**, then you can set the {@link sendTimeout} option
     *   to `0` to effectively force {@link send}() to always resolve immediately.
     *   Be prepared to catch exceptions if sending a message is not immediately
     *   possible.
     *
     * * If you wish to send on a socket and **messages should be queued before
     *   they are dropped**, you should implement a [simple
     *   queue](examples/queue/queue.ts) in JavaScript. Such a queue is not
     *   provided by this library because most real world applications need to
     *   deal with undeliverable messages in more complex ways - for example, they
     *   might need to reply with a status message; or first retry delivery a
     *   certain number of times before giving up.
     *
     * @param message Single message or multipart message to queue for sending.
     * @param options Any options, if applicable to the socket type (DRAFT only).
     * @returns Resolved when the message was successfully queued.
     */
    send(message: M, ...options: O): Promise<void>;
}
type ReceiveType<T> = T extends {
    receive(): Promise<infer U>;
} ? U : never;
/**
 * Describes sockets that can receive messages.
 *
 * @typeparam M The type of the message or message parts that can be read.
 */
export interface Readable<M extends object[] = Message[]> {
    /**
     * ZMQ_RCVBUF
     *
     * Underlying kernel receive buffer size in bytes. A value of -1 means leave
     * the OS default unchanged.
     */
    receiveBufferSize: number;
    /**
     * ZMQ_RCVHWM
     *
     * The high water mark is a hard limit on the maximum number of incoming
     * messages ØMQ shall queue in memory for any single peer that the specified
     * socket is communicating with. A value of zero means no limit.
     *
     * If this limit has been reached the socket shall enter an exceptional state
     * and depending on the socket type, ØMQ shall take appropriate action such as
     * blocking or dropping sent messages.
     */
    receiveHighWaterMark: number;
    /**
     * ZMQ_RCVTIMEO
     *
     * Sets the timeout receiving messages on the socket. If the value is 0,
     * {@link receive}() will return a rejected promise immediately if there is no
     * message to receive. If the value is -1, it will wait asynchronously until a
     * message is available. For all other values, it will wait for a message for
     * that amount of time before rejecting.
     */
    receiveTimeout: number;
    /**
     * Waits for the next single or multipart message to become availeble on the
     * socket. Reads a message immediately if possible. If no messages can be
     * read, it will wait asynchonously. The promise will be resolved with an
     * array containing the parts of the next message when available.
     *
     * ```typescript
     * const [msg] = await socket.receive()
     * const [part1, part2] = await socket.receive()
     * ```
     *
     * Reading may fail (eventually) if the socket has been configured with a
     * {@link receiveTimeout}.
     *
     * A call to {@link receive}() is guaranteed to return with a resolved promise
     * immediately if a message could be read from the socket directly.
     *
     * Only **one** asynchronously blocking call to {@link receive}() can be in
     * progress simultaneously. If you call {@link receive}() again on the same
     * socket it will return a rejected promise with an `EBUSY` error. For
     * example, if no messages can be read and no `await` is used:
     *
     * ```typescript
     * socket.receive() // -> pending promise until read is possible
     * socket.receive() // -> promise rejection with `EBUSY` error
     * ```
     *
     * **Note:** Due to the nature of Node.js and to avoid blocking the main
     * thread, this method always attempts to read messages with the
     * `ZMQ_DONTWAIT` flag. It polls asynchronously if reading is not currently
     * possible. This means that all functionality related to timeouts and
     * blocking behaviour is reimplemented in the Node.js bindings. Any
     * differences in behaviour with the native ZMQ library is considered a bug.
     *
     * @returns Resolved with message parts that were successfully read.
     */
    receive(): Promise<M>;
    /**
     * Asynchronously iterate over messages becoming available on the socket. When
     * the socket is closed with {@link Socket.close}(), the iterator will return.
     * Returning early from the iterator will **not** close the socket unless it
     * also goes out of scope.
     *
     * ```typescript
     * for await (const [msg] of socket) {
     *   // handle messages
     * }
     * ```
     */
    [Symbol.asyncIterator](): AsyncIterator<ReceiveType<this>, undefined>;
}
/**
 * Represents the options that can be assigned in the constructor of a given
 * socket type, for example `new Dealer({...})`. Readonly options
 * for the particular socket will be omitted.
 *
 * @typeparam S The socket type to which the options should be applied.
 */
export type SocketOptions<S extends Socket> = Options<S, {
    context: Context;
}>;
export interface EventSubscriber {
    /**
     * Adds a listener function which will be invoked when the given event type is
     * observed. Calling this method will convert the {@link Observer} to **event
     * emitter mode**, which will make it impossible to call
     * {@link Observer.receive}() at the same time.
     *
     * ```typescript
     * socket.events.on("bind", event => {
     *   console.log(`Socket bound to ${event.address}`)
     *   // ...
     * })
     * ```
     *
     * @param type The type of event to listen for.
     * @param listener The listener function that will be called with all event
     * data when the event is observed.
     */
    on<E extends EventType>(type: E, listener: (data: EventOfType<E>) => void): EventSubscriber;
    /**
     * Removes the specified listener function from the list of functions to call
     * when the given event is observed.
     *
     * @param type The type of event that the listener was listening for.
     * @param listener The previously registered listener function.
     */
    off<E extends EventType>(type: E, listener: (data: EventOfType<E>) => void): EventSubscriber;
}
declare module "./native" {
    interface Context {
        /**
         * ZMQ_BLOCKY
         *
         * By default the context will block forever when closed at process exit.
         * The assumption behind this behavior is that abrupt termination will cause
         * message loss. Most real applications use some form of handshaking to
         * ensure applications receive termination messages, and then terminate the
         * context with {@link Socket.linger} set to zero on all sockets. This
         * setting is an easier way to get the same result. When {@link blocky} is
         * set to `false`, all new sockets are given a linger timeout of zero. You
         * must still close all sockets before exiting.
         */
        blocky: boolean;
        /**
         * ZMQ_IO_THREADS
         *
         * Size of the ØMQ thread pool to handle I/O operations. If your application
         * is using only the `inproc` transport for messaging you may set this to
         * zero, otherwise set it to at least one (default).
         */
        ioThreads: number;
        /**
         * ZMQ_MAX_MSGSZ
         *
         * Maximum allowed size of a message sent in the context.
         */
        maxMessageSize: number;
        /**
         * ZMQ_MAX_SOCKETS
         *
         * Maximum number of sockets allowed on the context.
         */
        maxSockets: number;
        /**
         * ZMQ_IPV6
         *
         * Enable or disable IPv6. When IPv6 is enabled, a socket will connect to,
         * or accept connections from, both IPv4 and IPv6 hosts.
         */
        ipv6: boolean;
        /**
         * ZMQ_THREAD_PRIORITY
         *
         * Scheduling priority for internal context's thread pool. This option is
         * not available on Windows. Supported values for this option depend on
         * chosen scheduling policy. Details can be found at
         * http://man7.org/linux/man-pages/man2/sched_setscheduler.2.html. This
         * option only applies before creating any sockets on the context.
         *
         * @writeonly
         */
        threadPriority: number;
        /**
         * ZMQ_THREAD_SCHED_POLICY
         *
         * Scheduling policy for internal context's thread pool. This option is not
         * available on Windows. Supported values for this option can be found at
         * http://man7.org/linux/man-pages/man2/sched_setscheduler.2.html. This
         * option only applies before creating any sockets on the context.
         *
         * @writeonly
         */
        threadSchedulingPolicy: number;
        /**
         * ZMQ_SOCKET_LIMIT
         *
         * Largest number of sockets that can be set with {@link maxSockets}.
         *
         * @readonly
         */
        readonly maxSocketsLimit: number;
    }
    /**
     * Socket option names differ somewhat from the native libzmq option names.
     * This is intentional to improve readability and be more idiomatic for
     * JavaScript/TypeScript.
     */
    interface Socket {
        /**
         * ZMQ_AFFINITY
         *
         * I/O thread affinity, which determines which threads from the ØMQ I/O
         * thread pool associated with the socket's context shall handle newly
         * created connections.
         *
         * **Note:** This value is a bit mask, but values higher than
         * `Number.MAX_SAFE_INTEGER` may not be represented accurately! This
         * currently means that configurations beyond 52 threads are unreliable.
         */
        affinity: number;
        /**
         * ZMQ_RATE
         *
         * Maximum send or receive data rate for multicast transports such as `pgm`.
         */
        rate: number;
        /**
         * ZMQ_RECOVERY_IVL
         *
         * Maximum time in milliseconds that a receiver can be absent from a
         * multicast group before unrecoverable data loss will occur.
         */
        recoveryInterval: number;
        /**
         * ZMQ_LINGER
         *
         * Determines how long pending messages which have yet to be sent to a peer
         * shall linger in memory after a socket is closed with {@link close}().
         */
        linger: number;
        /**
         * ZMQ_RECONNECT_IVL
         *
         * Period ØMQ shall wait between attempts to reconnect disconnected peers
         * when using connection-oriented transports. The value -1 means no
         * reconnection.
         */
        reconnectInterval: number;
        /**
         * ZMQ_BACKLOG
         *
         * Maximum length of the queue of outstanding peer connections for the
         * specified socket. This only applies to connection-oriented transports.
         */
        backlog: number;
        /**
         * ZMQ_RECONNECT_IVL_MAX
         *
         * Maximum period ØMQ shall wait between attempts to reconnect. On each
         * reconnect attempt, the previous interval shall be doubled until
         * {@link reconnectMaxInterval} is reached. This allows for exponential
         * backoff strategy. Zero (the default) means no exponential backoff is
         * performed and reconnect interval calculations are only based on
         * {@link reconnectInterval}.
         */
        reconnectMaxInterval: number;
        /**
         * ZMQ_MAXMSGSIZE
         *
         * Limits the size of the inbound message. If a peer sends a message larger
         * than the limit it is disconnected. Value of -1 means no limit.
         */
        maxMessageSize: number;
        /**
         * ZMQ_TCP_KEEPALIVE
         *
         * Override SO_KEEPALIVE socket option (if supported by OS). The default
         * value of -1 leaves it to the OS default.
         */
        tcpKeepalive: number;
        /**
         * ZMQ_TCP_KEEPALIVE_CNT
         *
         * Overrides TCP_KEEPCNT socket option (if supported by OS). The default
         * value of -1 leaves it to the OS default.
         */
        tcpKeepaliveCount: number;
        /**
         * ZMQ_TCP_KEEPALIVE_IDLE
         *
         * Overrides TCP_KEEPIDLE / TCP_KEEPALIVE socket option (if supported by
         * OS). The default value of -1 leaves it to the OS default.
         */
        tcpKeepaliveIdle: number;
        /**
         * ZMQ_TCP_KEEPALIVE_INTVL
         *
         * Overrides TCP_KEEPINTVL socket option (if supported by the OS). The
         * default value of -1 leaves it to the OS default.
         */
        tcpKeepaliveInterval: number;
        /**
         * ZMQ_TCP_ACCEPT_FILTER
         *
         * Assign a filter that will be applied for each new TCP transport
         * connection on a listening socket. If no filters are applied, then the TCP
         * transport allows connections from any IP address. If at least one filter
         * is applied then new connection source IP should be matched. To clear all
         * filters set to `null`. Filter is a string with IPv6 or IPv4 CIDR.
         */
        tcpAcceptFilter: string | null;
        /**
         * ZMQ_IMMEDIATE
         *
         * By default queues will fill on outgoing connections even if the
         * connection has not completed. This can lead to "lost" messages on sockets
         * with round-robin routing ({@link Request}, {@link Push}, {@link Dealer}).
         * If this option is set to `true`, messages shall be queued only to
         * completed connections. This will cause the socket to block if there are
         * no other connections, but will prevent queues from filling on pipes
         * awaiting connection.
         */
        immediate: boolean;
        /**
         * ZMQ_IPV6
         *
         * Enable or disable IPv6. When IPv6 is enabled, the socket will connect to,
         * or accept connections from, both IPv4 and IPv6 hosts.
         */
        ipv6: boolean;
        /**
         * ZMQ_PLAIN_SERVER
         *
         * Defines whether the socket will act as server for PLAIN security. A value
         * of `true` means the socket will act as PLAIN server. A value of `false`
         * means the socket will not act as PLAIN server, and its security role then
         * depends on other option settings.
         */
        plainServer: boolean;
        /**
         * ZMQ_PLAIN_USERNAME
         *
         * Sets the username for outgoing connections over TCP or IPC. If you set
         * this to a non-null value, the security mechanism used for connections
         * shall be PLAIN.
         */
        plainUsername: string | null;
        /**
         * ZMQ_PLAIN_PASSWORD
         *
         * Sets the password for outgoing connections over TCP or IPC. If you set
         * this to a non-null value, the security mechanism used for connections
         * shall be PLAIN.
         */
        plainPassword: string | null;
        /**
         * ZMQ_CURVE_SERVER
         *
         * Defines whether the socket will act as server for CURVE security. A value
         * of `true` means the socket will act as CURVE server. A value of `false`
         * means the socket will not act as CURVE server, and its security role then
         * depends on other option settings.
         */
        curveServer: boolean;
        /**
         * ZMQ_CURVE_PUBLICKEY
         *
         * Sets the socket's long term public key. You must set this on CURVE client
         * sockets. A server socket does not need to know its own public key. You
         * can create a new keypair with {@link curveKeyPair}().
         */
        curvePublicKey: string | null;
        /**
         * ZMQ_CURVE_SECRETKEY
         *
         * Sets the socket's long term secret key. You must set this on both CURVE
         * client and server sockets. You can create a new keypair with
         * {@link curveKeyPair}().
         */
        curveSecretKey: string | null;
        /**
         * ZMQ_CURVE_SERVERKEY
         *
         * Sets the socket's long term server key. This is the public key of the
         * CURVE *server* socket. You must set this on CURVE *client* sockets. This
         * key must have been generated together with the server's secret key. You
         * can create a new keypair with {@link curveKeyPair}().
         */
        curveServerKey: string | null;
        /** */
        gssapiServer: boolean;
        /** */
        gssapiPrincipal: string | null;
        /** */
        gssapiServicePrincipal: string | null;
        /** */
        gssapiPlainText: boolean;
        /** */
        gssapiPrincipalNameType: "hostBased" | "userName" | "krb5Principal";
        /** */
        gssapiServicePrincipalNameType: "hostBased" | "userName" | "krb5Principal";
        /**
         * ZMQ_ZAP_DOMAIN
         *
         * Sets the domain for ZAP (ZMQ RFC 27) authentication. For NULL security
         * (the default on all `tcp://` connections), ZAP authentication only
         * happens if you set a non-empty domain. For PLAIN and CURVE security, ZAP
         * requests are always made, if there is a ZAP handler present. See
         * http://rfc.zeromq.org/spec:27 for more details.
         */
        zapDomain: string | null;
        /**
         * ZMQ_TOS
         *
         * Sets the ToS fields (the *Differentiated Services* (DS) and *Explicit
         * Congestion Notification* (ECN) field) of the IP header. The ToS field is
         * typically used to specify a packet's priority. The availability of this
         * option is dependent on intermediate network equipment that inspect the
         * ToS field and provide a path for low-delay, high-throughput,
         * highly-reliable service, etc.
         */
        typeOfService: number;
        /**
         * ZMQ_HANDSHAKE_IVL
         *
         * Handshaking is the exchange of socket configuration information (socket
         * type, identity, security) that occurs when a connection is first opened
         * (only for connection-oriented transports). If handshaking does not
         * complete within the configured time, the connection shall be closed. The
         * value 0 means no handshake time limit.
         */
        handshakeInterval: number;
        /**
         * ZMQ_SOCKS_PROXY
         *
         * The SOCKS5 proxy address that shall be used by the socket for the TCP
         * connection(s). Does not support SOCKS5 authentication. If the endpoints
         * are domain names instead of addresses they shall not be resolved and they
         * shall be forwarded unchanged to the SOCKS proxy service in the client
         * connection request message (address type 0x03 domain name).
         */
        socksProxy: string | null;
        /**
         * ZMQ_HEARTBEAT_IVL
         *
         * Interval in milliseconds between sending ZMTP heartbeats for the
         * specified socket. If this option is greater than 0, then a PING ZMTP
         * command will be sent after every interval.
         */
        heartbeatInterval: number;
        /**
         * ZMQ_HEARTBEAT_TTL
         *
         * The timeout in milliseconds on the remote peer for ZMTP heartbeats. If
         * this option is greater than 0, the remote side shall time out the
         * connection if it does not receive any more traffic within the TTL period.
         * This option does not have any effect if {@link heartbeatInterval} is 0.
         * Internally, this value is rounded down to the nearest decisecond, any
         * value less than 100 will have no effect.
         */
        heartbeatTimeToLive: number;
        /**
         * ZMQ_HEARTBEAT_TIMEOUT
         *
         * How long (in milliseconds) to wait before timing-out a connection after
         * sending a PING ZMTP command and not receiving any traffic. This option is
         * only valid if {@link heartbeatInterval} is greater than 0. The connection
         * will time out if there is no traffic received after sending the PING
         * command. The received traffic does not have to be a PONG command - any
         * received traffic will cancel the timeout.
         */
        heartbeatTimeout: number;
        /**
         * ZMQ_CONNECT_TIMEOUT
         *
         * Sets how long to wait before timing-out a connect() system call. The
         * connect() system call normally takes a long time before it returns a time
         * out error. Setting this option allows the library to time out the call at
         * an earlier interval.
         */
        connectTimeout: number;
        /**
         * ZMQ_TCP_MAXRT
         *
         * Sets how long before an unacknowledged TCP retransmit times out (if
         * supported by the OS). The system normally attempts many TCP retransmits
         * following an exponential backoff strategy. This means that after a
         * network outage, it may take a long time before the session can be
         * re-established. Setting this option allows the timeout to happen at a
         * shorter interval.
         */
        tcpMaxRetransmitTimeout: number;
        /**
         * ZMQ_MULTICAST_MAXTPDU
         *
         * Sets the maximum transport data unit size used for outbound multicast
         * packets. This must be set at or below the minimum Maximum Transmission
         * Unit (MTU) for all network paths over which multicast reception is
         * required.
         */
        multicastMaxTransportDataUnit: number;
        /**
         * ZMQ_VMCI_BUFFER_SIZE
         *
         * The size of the underlying buffer for the socket. Used during negotiation
         * before the connection is established.
         * For `vmci://` transports only.
         */
        vmciBufferSize: number;
        /**
         * ZMQ_VMCI_BUFFER_MIN_SIZE
         *
         * Minimum size of the underlying buffer for the socket. Used during
         * negotiation before the connection is established.
         * For `vmci://` transports only.
         */
        vmciBufferMinSize: number;
        /**
         * ZMQ_VMCI_BUFFER_MAX_SIZE
         *
         * Maximum size of the underlying buffer for the socket. Used during
         * negotiation before the connection is established.
         * For `vmci://` transports only.
         */
        vmciBufferMaxSize: number;
        /**
         * ZMQ_VMCI_CONNECT_TIMEOUT
         *
         * Connection timeout for the socket.
         * For `vmci://` transports only.
         */
        vmciConnectTimeout: number;
        /**
         * ZMQ_BINDTODEVICE
         *
         * Binds the socket to the given network interface (Linux only). Allows to
         * use Linux VRF, see:
         * https://www.kernel.org/doc/Documentation/networking/vrf.txt. Requires the
         * program to be ran as root **or** with `CAP_NET_RAW`.
         */
        interface: string | null;
        /**
         * ZMQ_ZAP_ENFORCE_DOMAIN
         *
         * The ZAP (ZMQ RFC 27) authentication protocol specifies that a domain must
         * always be set. Older versions of libzmq did not follow the spec and
         * allowed an empty domain to be set. This option can be used to enabled or
         * disable the stricter, backward incompatible behaviour. For now it is
         * disabled by default, but in a future version it will be enabled by
         * default.
         */
        zapEnforceDomain: boolean;
        /**
         * ZMQ_LOOPBACK_FASTPATH
         *
         * Enable faster TCP connections on loopback devices. An application can
         * enable this option to reduce the latency and improve the performance of
         * loopback operations on a TCP socket on Windows.
         *
         * @windows
         */
        loopbackFastPath: boolean;
        /**
         * ZMQ_TYPE
         *
         * Retrieve the socket type. This is fairly useless because you can test the
         * socket class with e.g. `socket instanceof Dealer`.
         *
         * @readonly
         */
        readonly type: SocketType;
        /**
         * ZMQ_LAST_ENDPOINT
         *
         * The last endpoint bound for TCP and IPC transports.
         *
         * @readonly
         */
        readonly lastEndpoint: string | null;
        /**
         * ZMQ_MECHANISM
         *
         * Returns the current security mechanism for the socket, if any. The
         * security mechanism is set implictly by using any of the relevant security
         * options. The returned value is one of:
         * * `null` - No security mechanism is used.
         * * `"plain"` - The PLAIN mechanism defines a simple username/password
         *   mechanism that lets a server authenticate a client. PLAIN makes no
         *   attempt at security or confidentiality.
         * * `"curve"` - The CURVE mechanism defines a mechanism for secure
         *   authentication and confidentiality for communications between a client
         *   and a server. CURVE is intended for use on public networks.
         * * `"gssapi"` - The GSSAPI mechanism defines a mechanism for secure
         *   authentication and confidentiality for communications between a client
         *   and a server using the Generic Security Service Application Program
         *   Interface (GSSAPI). The GSSAPI mechanism can be used on both public and
         *   private networks.
         *
         * @readonly
         */
        readonly securityMechanism: null | "plain" | "curve" | "gssapi";
        /**
         * ZMQ_THREAD_SAFE
         *
         * Whether or not the socket is threadsafe. Currently only DRAFT sockets is
         * thread-safe.
         *
         * @readonly
         */
        readonly threadSafe: boolean;
    }
    interface Observer extends EventSubscriber {
        /**
         * Asynchronously iterate over socket events. When the socket is closed or
         * when the observer is closed manually with {@link Observer.close}(), the
         * iterator will return.
         *
         * ```typescript
         * for await (event of socket.events) {
         *   switch (event.type) {
         *     case "bind":
         *       console.log(`Socket bound to ${event.address}`)
         *       break
         *     // ...
         *   }
         * }
         * ```
         */
        [Symbol.asyncIterator](): AsyncIterator<ReceiveType<this>, undefined>;
    }
}
/**
 * A {@link Pair} socket can only be connected to one other {@link Pair} at any
 * one time. No message routing or filtering is performed on any messages.
 *
 * When a {@link Pair} socket enters the mute state due to having reached the
 * high water mark for the connected peer, or if no peer is connected, then any
 * {@link Writable.send}() operations on the socket shall block until the peer
 * becomes available for sending; messages are not discarded.
 *
 * While {@link Pair} sockets can be used over transports other than
 * `inproc://`, their inability to auto-reconnect coupled with the fact new
 * incoming connections will be terminated while any previous connections
 * (including ones in a closing state) exist makes them unsuitable for `tcp://`
 * in most cases.
 */
export declare class Pair extends Socket {
    constructor(options?: SocketOptions<Pair>);
}
export interface Pair extends Writable, Readable {
}
/**
 * A {@link Publisher} socket is used to distribute data to {@link Subscriber}s.
 * Messages sent are distributed in a fan out fashion to all connected peers.
 * This socket cannot receive messages.
 *
 * When a {@link Publisher} enters the mute state due to having reached the high
 * water mark for a connected {@link Subscriber}, then any messages that would
 * be sent to the subscriber in question shall instead be dropped until the mute
 * state ends. The {@link Writable.send}() method will never block.
 */
export declare class Publisher extends Socket {
    /**
     * ZMQ_XPUB_NODROP
     *
     * Sets the socket behaviour to return an error if the high water mark is
     * reached and the message could not be send. The default is to drop the
     * message silently when the peer high water mark is reached.
     */
    noDrop: boolean;
    /**
     * ZMQ_CONFLATE
     *
     * If set to `true`, a socket shall keep only one message in its
     * inbound/outbound queue: the last message to be received/sent. Ignores any
     * high water mark options. Does not support multi-part messages - in
     * particular, only one part of it is kept in the socket internal queue.
     */
    conflate: boolean;
    /**
     * ZMQ_INVERT_MATCHING
     *
     * Causes messages to be sent to all connected sockets except those subscribed
     * to a prefix that matches the message.
     *
     * All {@link Subscriber} sockets connecting to the {@link Publisher} must
     * also have the option set to `true`. Failure to do so will have the
     * {@link Subscriber} sockets reject everything the {@link Publisher} socket
     * sends them.
     */
    invertMatching: boolean;
    constructor(options?: SocketOptions<Publisher>);
}
export interface Publisher extends Writable {
}
/**
 * A {@link Subscriber} socket is used to subscribe to data distributed by a
 * {@link Publisher}. Initially a {@link Subscriber} is not subscribed to any
 * messages. Use {@link Subscriber.subscribe}() to specify which messages to
 * subscribe to. This socket cannot send messages.
 */
export declare class Subscriber extends Socket {
    /**
     * ZMQ_CONFLATE
     *
     * If set to `true`, a socket shall keep only one message in its
     * inbound/outbound queue: the last message to be received/sent. Ignores any
     * high water mark options. Does not support multi-part messages - in
     * particular, only one part of it is kept in the socket internal queue.
     */
    conflate: boolean;
    /**
     * ZMQ_INVERT_MATCHING
     *
     * Causes incoming messages that do not match any of the socket's
     * subscriptions to be received by the user.
     *
     * All {@link Subscriber} sockets connecting to a {@link Publisher} must also
     * have the option set to `true`. Failure to do so will have the
     * {@link Subscriber} sockets reject everything the {@link Publisher} socket
     * sends them.
     */
    invertMatching: boolean;
    constructor(options?: SocketOptions<Subscriber>);
    /**
     * Establish a new message filter. Newly created {@link Subsriber} sockets
     * will filtered out all incoming messages. Call this method to subscribe to
     * messages beginning with the given prefix.
     *
     * Multiple filters may be attached to a single socket, in which case a
     * message shall be accepted if it matches at least one filter. Subscribing
     * without any filters shall subscribe to **all** incoming messages.
     *
     * ```typescript
     * const sub = new Subscriber()
     *
     * // Listen to all messages beginning with 'foo'.
     * sub.subscribe("foo")
     *
     * // Listen to all incoming messages.
     * sub.subscribe()
     * ```
     *
     * @param prefixes The prefixes of messages to subscribe to.
     */
    subscribe(...prefixes: Array<Buffer | string>): void;
    /**
     * Remove an existing message filter which was previously established with
     * {@link subscribe}(). Stops receiving messages with the given prefix.
     *
     * Unsubscribing without any filters shall unsubscribe from the "subscribe
     * all" filter that is added by calling {@link subscribe}() without arguments.
     *
     * ```typescript
     * const sub = new Subscriber()
     *
     * // Listen to all messages beginning with 'foo'.
     * sub.subscribe("foo")
     * // ...
     *
     * // Stop listening to messages beginning with 'foo'.
     * sub.unsubscribe("foo")
     * ```
     *
     * @param prefixes The prefixes of messages to subscribe to.
     */
    unsubscribe(...prefixes: Array<Buffer | string>): void;
}
export interface Subscriber extends Readable {
}
/**
 * A {@link Request} socket acts as a client to send requests to and receive
 * replies from a {@link Reply} socket. This socket allows only an alternating
 * sequence of {@link Writable.send}() and subsequent {@link Readable.receive}()
 * calls. Each request sent is round-robined among all services, and each reply
 * received is matched with the last issued request.
 *
 * If no services are available, then any send operation on the socket shall
 * block until at least one service becomes available. The REQ socket shall not
 * discard messages.
 */
export declare class Request extends Socket {
    /**
     * ZMQ_ROUTING_ID
     *
     * The identity of the specified socket when connecting to a `Router` socket.
     */
    routingId: string | null;
    /**
     * ZMQ_PROBE_ROUTER
     *
     * When set to `true`, the socket will automatically send an empty message
     * when a new connection is made or accepted. You may set this on sockets
     * connected to a {@link Router} socket. The application must filter such
     * empty messages. This option provides the {@link Router} with an event
     * signaling the arrival of a new peer.
     *
     * *Warning:** Do not set this option on a socket that talks to any other
     * socket type except {@link Router}: the results are undefined.
     *
     * @writeonly
     */
    probeRouter: boolean;
    /**
     * ZMQ_REQ_CORRELATE
     *
     * The default behaviour of {@link Request} sockets is to rely on the ordering
     * of messages to match requests and responses and that is usually sufficient.
     * When this option is set to `true` the socket will prefix outgoing messages
     * with an extra frame containing a request id. That means the full message is
     * `[<request id>, `null`, user frames…]`. The {@link Request} socket will
     * discard all incoming messages that don't begin with these two frames.
     */
    correlate: boolean;
    /**
     * ZMQ_REQ_RELAXED
     *
     * By default, a {@link Request} socket does not allow initiating a new
     * request until the reply to the previous one has been received. When set to
     * `true`, sending another message is allowed and previous replies will be
     * discarded. The request-reply state machine is reset and a new request is
     * sent to the next available peer.
     *
     * **Note:** If set to `true`, also enable {@link correlate} to ensure correct
     * matching of requests and replies. Otherwise a late reply to an aborted
     * request can be reported as the reply to the superseding request.
     */
    relaxed: boolean;
    constructor(options?: SocketOptions<Request>);
}
export interface Request extends Readable, Writable {
}
/**
 * A {@link Reply} socket can act as a server which receives requests from and
 * sends replies to a {@link Request} socket. This socket type allows only an
 * alternating sequence of {@link Readable.receive}() and subsequent
 * {@link Writable.send}() calls. Each request received is fair-queued from
 * among all clients, and each reply sent is routed to the client that issued
 * the last request. If the original requester does not exist any more the reply
 * is silently discarded.
 */
export declare class Reply extends Socket {
    /**
     * ZMQ_ROUTING_ID
     *
     * The identity of the specified socket when connecting to a `Router` socket.
     */
    routingId: string | null;
    constructor(options?: SocketOptions<Reply>);
}
export interface Reply extends Readable, Writable {
}
/**
 * A {@link Dealer} socket can be used to extend request/reply sockets. Each
 * message sent is round-robined among all connected peers, and each message
 * received is fair-queued from all connected peers.
 *
 * When a {@link Dealer} socket enters the mute state due to having reached the
 * high water mark for all peers, or if there are no peers at all, then any
 * {@link Writable.send}() operations on the socket shall block until the mute
 * state ends or at least one peer becomes available for sending; messages are
 * not discarded.
 *
 * When a {@link Dealer} is connected to a {@link Reply} socket, each message
 * sent must consist of an empty message part, the delimiter, followed by one or
 * more body parts.
 */
export declare class Dealer extends Socket {
    /**
     * ZMQ_ROUTING_ID
     *
     * The identity of the specified socket when connecting to a `Router` socket.
     */
    routingId: string | null;
    /**
     * ZMQ_PROBE_ROUTER
     *
     * When set to `true`, the socket will automatically send an empty message
     * when a new connection is made or accepted. You may set this on sockets
     * connected to a {@link Router} socket. The application must filter such
     * empty messages. This option provides the {@link Router} with an event
     * signaling the arrival of a new peer.
     *
     * *Warning:** Do not set this option on a socket that talks to any other
     * socket type except {@link Router}: the results are undefined.
     *
     * @writeonly
     */
    probeRouter: boolean;
    /**
     * ZMQ_CONFLATE
     *
     * If set to `true`, a socket shall keep only one message in its
     * inbound/outbound queue: the last message to be received/sent. Ignores any
     * high water mark options. Does not support multi-part messages - in
     * particular, only one part of it is kept in the socket internal queue.
     */
    conflate: boolean;
    constructor(options?: SocketOptions<Dealer>);
}
export interface Dealer extends Readable, Writable {
}
/**
 * A {@link Router} can be used to extend request/reply sockets. When receiving
 * messages a {@link Router} shall prepend a message part containing the routing
 * id of the originating peer to the message. Messages received are fair-queued
 * from among all connected peers. When sending messages, the first part of the
 * message is removed and used to determine the routing id of the peer the
 * message should be routed to.
 *
 * If the peer does not exist anymore, or has never existed, the message shall
 * be silently discarded. However, if {@link Router.mandatory} is set to `true`,
 * the socket shall fail with a `EHOSTUNREACH` error in both cases.
 *
 * When a {@link Router} enters the mute state due to having reached the high
 * water mark for all peers, then any messages sent to the socket shall be
 * dropped until the mute state ends. Likewise, any messages routed to a peer
 * for which the individual high water mark has been reached shall also be
 * dropped. If {@link Router.mandatory} is set to `true` the socket shall block
 * or return an `EAGAIN` error in both cases.
 *
 * When a {@link Request} socket is connected to a {@link Router}, in addition
 * to the routing id of the originating peer each message received shall contain
 * an empty delimiter message part. Hence, the entire structure of each received
 * message as seen by the application becomes: one or more routing id parts,
 * delimiter part, one or more body parts. When sending replies to a
 * {@link Request} the delimiter part must be included.
 */
export declare class Router extends Socket {
    /**
     * ZMQ_ROUTING_ID
     *
     * The identity of the specified socket when connecting to a `Router` socket.
     */
    routingId: string | null;
    /**
     * ZMQ_ROUTER_MANDATORY
     *
     * A value of `false` is the default and discards the message silently when it
     * cannot be routed or the peer's high water mark is reached. A value of
     * `true` causes {@link send}() to fail if it cannot be routed, or wait
     * asynchronously if the high water mark is reached.
     */
    mandatory: boolean;
    /**
     * ZMQ_PROBE_ROUTER
     *
     * When set to `true`, the socket will automatically send an empty message
     * when a new connection is made or accepted. You may set this on sockets
     * connected to a {@link Router} socket. The application must filter such
     * empty messages. This option provides the {@link Router} with an event
     * signaling the arrival of a new peer.
     *
     * *Warning:** Do not set this option on a socket that talks to any other
     * socket type except {@link Router}: the results are undefined.
     *
     * @writeonly
     */
    probeRouter: boolean;
    /**
     * ZMQ_ROUTER_HANDOVER
     *
     * If two clients use the same identity when connecting to a {@link Router},
     * the results shall depend on the this option. If it set to `false`
     * (default), the {@link Router} socket shall reject clients trying to connect
     * with an already-used identity. If it is set to `true`, the {@link Router}
     * socket shall hand-over the connection to the new client and disconnect the
     * existing one.
     */
    handover: boolean;
    constructor(options?: SocketOptions<Router>);
    /**
     * Connects to the given remote address. To specificy a specific routing id,
     * provide a `routingId` option. The identity should be unique, from 1 to 255
     * bytes long and MAY NOT start with binary zero.
     *
     * @param address The `tcp://` address to connect to.
     * @param options Any connection options.
     */
    connect(address: string, options?: RouterConnectOptions): void;
}
export interface RouterConnectOptions {
    routingId?: string;
}
export interface Router extends Readable, Writable {
}
/**
 * A {@link Pull} socket is used by a pipeline node to receive messages from
 * upstream pipeline nodes. Messages are fair-queued from among all connected
 * upstream nodes. This socket cannot send messages.
 */
export declare class Pull extends Socket {
    constructor(options?: SocketOptions<Pull>);
}
export interface Pull extends Readable {
    /**
     * ZMQ_CONFLATE
     *
     * If set to `true`, a socket shall keep only one message in its
     * inbound/outbound queue: the last message to be received/sent. Ignores any
     * high water mark options. Does not support multi-part messages - in
     * particular, only one part of it is kept in the socket internal queue.
     */
    conflate: boolean;
}
/**
 * A {@link Push} socket is used by a pipeline node to send messages to
 * downstream pipeline nodes. Messages are round-robined to all connected
 * downstream nodes. This socket cannot receive messages.
 *
 * When a {@link Push} socket enters the mute state due to having reached the
 * high water mark for all downstream nodes, or if there are no downstream nodes
 * at all, then {@link Writable.send}() will block until the mute state ends or
 * at least one downstream node becomes available for sending; messages are not
 * discarded.
 */
export declare class Push extends Socket {
    constructor(options?: SocketOptions<Push>);
}
export interface Push extends Writable {
    /**
     * ZMQ_CONFLATE
     *
     * If set to `true`, a socket shall keep only one message in its
     * inbound/outbound queue: the last message to be received/sent. Ignores any
     * high water mark options. Does not support multi-part messages - in
     * particular, only one part of it is kept in the socket internal queue.
     */
    conflate: boolean;
}
/**
 * Same as {@link Publisher}, except that you can receive subscriptions from the
 * peers in form of incoming messages. Subscription message is a byte 1 (for
 * subscriptions) or byte 0 (for unsubscriptions) followed by the subscription
 * body. Messages without a sub/unsub prefix are also received, but have no
 * effect on subscription status.
 */
export declare class XPublisher extends Socket {
    /**
     * ZMQ_XPUB_NODROP
     *
     * Sets the socket behaviour to return an error if the high water mark is
     * reached and the message could not be send. The default is to drop the
     * message silently when the peer high water mark is reached.
     */
    noDrop: boolean;
    /**
     * ZMQ_XPUB_MANUAL
     *
     * Sets the {@link XPublisher} socket subscription handling mode to
     * manual/automatic. A value of `true` will change the subscription requests
     * handling to manual.
     */
    manual: boolean;
    /**
     * ZMQ_XPUB_WELCOME_MSG
     *
     * Sets a welcome message that will be recieved by subscriber when connecting.
     * Subscriber must subscribe to the welcome message before connecting. For
     * welcome messages to work well, poll on incoming subscription messages on
     * the {@link XPublisher} socket and handle them.
     */
    welcomeMessage: string | null;
    /**
     * ZMQ_INVERT_MATCHING
     *
     * Causes messages to be sent to all connected sockets except those subscribed
     * to a prefix that matches the message.
     */
    invertMatching: boolean;
    /**
     * ZMQ_XPUB_VERBOSE / ZMQ_XPUB_VERBOSER
     *
     * Whether to pass any duplicate subscription/unsuscription messages.
     *  * `null` (default) - Only unique subscribe and unsubscribe messages are
     *    visible to the caller.
     *  * `"allSubs"` - All subscribe messages (including duplicates) are visible
     *    to the caller, but only unique unsubscribe messages are visible.
     *  * `"allSubsUnsubs"` - All subscribe and unsubscribe messages (including
     *    duplicates) are visible to the caller.
     */
    set verbosity(value: null | "allSubs" | "allSubsUnsubs");
    constructor(options?: SocketOptions<XPublisher>);
}
export interface XPublisher extends Readable, Writable {
}
/**
 * Same as {@link Subscriber}, except that you subscribe by sending subscription
 * messages to the socket. Subscription message is a byte 1 (for subscriptions)
 * or byte 0 (for unsubscriptions) followed by the subscription body. Messages
 * without a sub/unsub prefix may also be sent, but have no effect on
 * subscription status.
 */
export declare class XSubscriber extends Socket {
    constructor(options?: SocketOptions<XSubscriber>);
}
export interface XSubscriber extends Readable, Writable {
}
/**
 * A {@link Stream} is used to send and receive TCP data from a non-ØMQ peer
 * with the `tcp://` transport. A {@link Stream} can act as client and/or
 * server, sending and/or receiving TCP data asynchronously.
 *
 * When sending and receiving data with {@link Writable.send}() and
 * {@link Readable.receive}(), the first message part shall be the routing id of
 * the peer. Unroutable messages will cause an error.
 *
 * When a connection is made to a {@link Stream}, a zero-length message will be
 * received. Similarly, when the peer disconnects (or the connection is lost), a
 * zero-length message will be received.
 *
 * To close a specific connection, {@link Writable.send}() the routing id frame
 * followed by a zero-length message.
 *
 * To open a connection to a server, use {@link Stream.connect}().
 */
export declare class Stream extends Socket {
    /**
     * ZMQ_STREAM_NOTIFY
     *
     * Enables connect and disconnect notifications on a {@link Stream} when set
     * to `true`. When notifications are enabled, the socket delivers a
     * zero-length message when a peer connects or disconnects.
     */
    notify: boolean;
    constructor(options?: SocketOptions<Stream>);
    /**
     * Connects to the given remote address. To specificy a specific routing id,
     * provide a `routingId` option. The identity should be unique, from 1 to 255
     * bytes long and MAY NOT start with binary zero.
     *
     * @param address The `tcp://` address to connect to.
     * @param options Any connection options.
     */
    connect(address: string, options?: StreamConnectOptions): void;
}
export interface StreamConnectOptions {
    routingId?: string;
}
export interface Stream extends Readable<[Message, Message]>, Writable<[MessageLike, MessageLike]> {
}