zmq

Python bindings for 0MQ.

Basic Classes

Context

class zmq.Context(io_threads=1, **kwargs)

Create a zmq Context

A zmq Context creates sockets via its ctx.socket method.

closed

boolean - whether the context has been terminated. If True, you can no longer use this Context.

destroy(linger=None)

ctx.destroy(linger=None)

Close all sockets associated with this context, and then terminate the context. If linger is specified, the LINGER sockopt of the sockets will be set prior to closing.

Warning

destroy involves calling zmq_close(), which is NOT threadsafe. If there are active sockets in other threads, this must not be called.

get(option)

ctx.get(option)

Get the value of a context option.

See the 0MQ API documentation for zmq_ctx_get for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Parameters:option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IO_THREADS, zmq.MAX_SOCKETS
Returns:optval – The value of the option as an integer.
Return type:int
getsockopt(opt)

get default socket options for new sockets created by this Context

New in version 13.0.

classmethod instance(io_threads=1)

Returns a global Context instance.

Most single-threaded applications have a single, global Context. Use this method instead of passing around Context instances throughout your code.

A common pattern for classes that depend on Contexts is to use a default argument to enable programs with multiple Contexts but not require the argument for simpler applications:

class MyClass(object):
def __init__(self, context=None):
self.context = context or Context.instance()
set(option, optval)

ctx.set(option, optval)

Set a context option.

See the 0MQ API documentation for zmq_ctx_set for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Parameters:
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.IO_THREADS, zmq.MAX_SOCKETS
    
  • optval (int) – The value of the option to set.
setsockopt(opt, value)

set default socket options for new sockets created by this Context

New in version 13.0.

classmethod shadow(address)

Shadow an existing libzmq context

address is the integer address of the libzmq context or an FFI pointer to it.

New in version 14.1.

classmethod shadow_pyczmq(ctx)

Shadow an existing pyczmq context

ctx is the FFI zctx_t * pointer

New in version 14.1.

socket(socket_type, **kwargs)

Create a Socket associated with this Context.

Parameters:
  • socket_type (int) – The socket type, which can be any of the 0MQ socket types: REQ, REP, PUB, SUB, PAIR, DEALER, ROUTER, PULL, PUSH, etc.
  • kwargs – will be passed to the __init__ method of the socket class.
term()

ctx.term()

Close or terminate the context.

This can be called to close the context by hand. If this is not called, the context will automatically be closed when it is garbage collected.

underlying

The address of the underlying libzmq context

Socket

class zmq.Socket(*a, **kw)

The ZMQ socket object

To create a Socket, first create a Context:

ctx = zmq.Context.instance()

then call ctx.socket(socket_type):

s = ctx.socket(zmq.ROUTER)
closed

boolean - whether the socket has been closed. If True, you can no longer use this Socket.

copy_threshold

integer - size (in bytes) below which messages should always be copied. Zero-copy support has nontrivial overhead due to the need to coordinate garbage collection with the libzmq IO thread, so sending small messages (typically < 10s of kB) with copy=False is often more expensive than with copy=True. The initial default value is 65536 (64kB), a reasonable default based on testing.

Defaults to zmq.COPY_THRESHOLD on socket construction. Setting zmq.COPY_THRESHOLD will define the default value for any subsequently created sockets.

New in version 17.

bind(addr)

s.bind(addr)

Bind the socket to an address.

This causes the socket to listen on a network port. Sockets on the other side of this connection will use Socket.connect(addr) to connect to this socket.

Parameters:addr (str) – The address string. This has the form ‘protocol://interface:port’, for example ‘tcp://127.0.0.1:5555’. Protocols supported include tcp, udp, pgm, epgm, inproc and ipc. If the address is unicode, it is encoded to utf-8 first.
bind_to_random_port(addr, min_port=49152, max_port=65536, max_tries=100)

bind this socket to a random port in a range

If the port range is unspecified, the system will choose the port.

Parameters:
  • addr (str) – The address string without the port to pass to Socket.bind().
  • min_port (int, optional) – The minimum port in the range of ports to try (inclusive).
  • max_port (int, optional) – The maximum port in the range of ports to try (exclusive).
  • max_tries (int, optional) – The maximum number of bind attempts to make.
Returns:

port – The port the socket was bound to.

Return type:

int

Raises:

ZMQBindError – if max_tries reached before successful bind

close(linger=None)

s.close(linger=None)

Close the socket.

If linger is specified, LINGER sockopt will be set prior to closing.

This can be called to close the socket by hand. If this is not called, the socket will automatically be closed when it is garbage collected.

connect(addr)

s.connect(addr)

Connect to a remote 0MQ socket.

Parameters:addr (str) – The address string. This has the form ‘protocol://interface:port’, for example ‘tcp://127.0.0.1:5555’. Protocols supported are tcp, upd, pgm, inproc and ipc. If the address is unicode, it is encoded to utf-8 first.
disable_monitor()

Shutdown the PAIR socket (created using get_monitor_socket) that is serving socket events.

New in version 14.4.

disconnect(addr)

s.disconnect(addr)

Disconnect from a remote 0MQ socket (undoes a call to connect).

New in version libzmq-3.2.

New in version 13.0.

Parameters:addr (str) – The address string. This has the form ‘protocol://interface:port’, for example ‘tcp://127.0.0.1:5555’. Protocols supported are tcp, upd, pgm, inproc and ipc. If the address is unicode, it is encoded to utf-8 first.
fileno()

Return edge-triggered file descriptor for this socket.

This is a read-only edge-triggered file descriptor for both read and write events on this socket. It is important that all available events be consumed when an event is detected, otherwise the read event will not trigger again.

New in version 17.0.

get(option)

s.get(option)

Get the value of a socket option.

See the 0MQ API documentation for details on specific options.

Parameters:option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IDENTITY, HWM, LINGER, FD, EVENTS
Returns:optval – The value of the option as a bytestring or int.
Return type:int or bytes
get_hwm()

get the High Water Mark

On libzmq ≥ 3, this gets SNDHWM if available, otherwise RCVHWM

get_monitor_socket(events=None, addr=None)

Return a connected PAIR socket ready to receive the event notifications.

New in version libzmq-4.0.

New in version 14.0.

Parameters:
  • events (bitfield (int) [default: ZMQ_EVENTS_ALL]) – The bitmask defining which events are wanted.
  • addr (string [default: None]) – The optional endpoint for the monitoring sockets.
Returns:

socket – The socket is already connected and ready to receive messages.

Return type:

(PAIR)

get_string(option, encoding='utf-8')

get the value of a socket option

See the 0MQ documentation for details on specific options.

Parameters:option (int) – The option to retrieve.
Returns:optval – The value of the option as a unicode string.
Return type:unicode string (unicode on py2, str on py3)
getsockopt

s.get(option)

Get the value of a socket option.

See the 0MQ API documentation for details on specific options.

Parameters:option (int) –

The option to get. Available values will depend on your version of libzmq. Examples include:

zmq.IDENTITY, HWM, LINGER, FD, EVENTS
Returns:optval – The value of the option as a bytestring or int.
Return type:int or bytes
getsockopt_string(option, encoding='utf-8')

get the value of a socket option

See the 0MQ documentation for details on specific options.

Parameters:option (int) – The option to retrieve.
Returns:optval – The value of the option as a unicode string.
Return type:unicode string (unicode on py2, str on py3)
hwm

get the High Water Mark

On libzmq ≥ 3, this gets SNDHWM if available, otherwise RCVHWM

join(group)

join(group)

Join a RADIO-DISH group

Only for DISH sockets.

libzmq and pyzmq must have been built with ZMQ_BUILD_DRAFT_API

New in version 17.

leave(group)

leave(group)

Leave a RADIO-DISH group

Only for DISH sockets.

libzmq and pyzmq must have been built with ZMQ_BUILD_DRAFT_API

New in version 17.

monitor(addr, flags)

s.monitor(addr, flags)

Start publishing socket events on inproc. See libzmq docs for zmq_monitor for details.

While this function is available from libzmq 3.2, pyzmq cannot parse monitor messages from libzmq prior to 4.0.

Parameters:
  • addr (str) – The inproc url used for monitoring. Passing None as the addr will cause an existing socket monitor to be deregistered.
  • events (int [default: zmq.EVENT_ALL]) – The zmq event bitmask for which events will be sent to the monitor.
poll(timeout=None, flags=1)

poll the socket for events

The default is to poll forever for incoming events. Timeout is in milliseconds, if specified.

Parameters:
  • timeout (int [default: None]) – The timeout (in milliseconds) to wait for an event. If unspecified (or specified None), will wait forever for an event.
  • flags (bitfield (int) [default: POLLIN]) – The event flags to poll for (any combination of POLLIN|POLLOUT). The default is to check for incoming events (POLLIN).
Returns:

events – The events that are ready and waiting. Will be 0 if no events were ready by the time timeout was reached.

Return type:

bitfield (int)

recv(flags=0, copy=True, track=False)

s.recv(flags=0, copy=True, track=False)

Receive a message.

Parameters:
  • flags (int) – Any supported flag: NOBLOCK. If NOBLOCK is set, this method will raise a ZMQError with EAGAIN if a message is not ready. If NOBLOCK is not set, then this method will block until a message arrives.
  • copy (bool) – Should the message be received in a copying or non-copying manner? If False a Frame object is returned, if True a string copy of message is returned.
  • track (bool) – Should the message be tracked for notification that ZMQ has finished with it? (ignored if copy=True)
Returns:

msg – The received message frame. If copy is False, then it will be a Frame, otherwise it will be bytes.

Return type:

bytes, Frame

Raises:

ZMQError – for any of the reasons zmq_msg_recv might fail.

recv_json(flags=0, **kwargs)

receive a Python object as a message using json to serialize

Keyword arguments are passed on to json.loads

Parameters:flags (int) – Any valid recv flag.
Returns:obj – The Python object that arrives as a message.
Return type:Python object
recv_multipart(flags=0, copy=True, track=False)

receive a multipart message as a list of bytes or Frame objects

Parameters:
  • flags (int, optional) – Any supported flag: NOBLOCK. If NOBLOCK is set, this method will raise a ZMQError with EAGAIN if a message is not ready. If NOBLOCK is not set, then this method will block until a message arrives.
  • copy (bool, optional) – Should the message frame(s) be received in a copying or non-copying manner? If False a Frame object is returned for each part, if True a copy of the bytes is made for each frame.
  • track (bool, optional) – Should the message frame(s) be tracked for notification that ZMQ has finished with it? (ignored if copy=True)
Returns:

msg_parts – A list of frames in the multipart message; either Frames or bytes, depending on copy.

Return type:

list

recv_pyobj(flags=0)

receive a Python object as a message using pickle to serialize

Parameters:flags (int) – Any valid recv flag.
Returns:obj – The Python object that arrives as a message.
Return type:Python object
recv_serialized(deserialize, flags=0, copy=True)

Receive a message with a custom deserialization function.

New in version 17.

Parameters:
  • deserialize (callable) – The deserialization function to use. deserialize will be called with one argument: the list of frames returned by recv_multipart() and can return any object.
  • flags (int, optional) – Any valid send flag.
  • copy (bool, optional) – Whether to recv bytes or Frame objects.
recv_string(flags=0, encoding='utf-8')

receive a unicode string, as sent by send_string

Parameters:
  • flags (int) – Any valid recv flag.
  • encoding (str [default: 'utf-8']) – The encoding to be used
Returns:

s – The Python unicode string that arrives as encoded bytes.

Return type:

unicode string (unicode on py2, str on py3)

send(data, flags=0, copy=True, track=False, routing_id=None, group=None)

Send a single zmq message frame on this socket.

Parameters:
  • data (bytes, Frame, memoryview) – The content of the message. This can be any object that provides the Python buffer API (i.e. memoryview(data) can be called).
  • flags (int) – Any supported flag: NOBLOCK, SNDMORE.
  • copy (bool) – Should the message be sent in a copying or non-copying manner.
  • track (bool) – Should the message be tracked for notification that ZMQ has finished with it? (ignored if copy=True)
  • routing_id (int) – For use with SERVER sockets
  • group (str) – For use with RADIO sockets
Returns:

  • None (if copy or not track) – None if message was sent, raises an exception otherwise.
  • MessageTracker (if track and not copy) – a MessageTracker object, whose pending property will be True until the send is completed.

Raises:
  • TypeError – If a unicode object is passed
  • ValueError – If track=True, but an untracked Frame is passed.
  • ZMQError – If the send does not succeed for any reason.
  • .. versionchanged:: 17.0 – DRAFT support for routing_id and group arguments.
send_json(obj, flags=0, **kwargs)

send a Python object as a message using json to serialize

Keyword arguments are passed on to json.dumps

Parameters:
  • obj (Python object) – The Python object to send
  • flags (int) – Any valid send flag
send_multipart(msg_parts, flags=0, copy=True, track=False, **kwargs)

send a sequence of buffers as a multipart message

The zmq.SNDMORE flag is added to all msg parts before the last.

Parameters:
  • msg_parts (iterable) – A sequence of objects to send as a multipart message. Each element can be any sendable object (Frame, bytes, buffer-providers)
  • flags (int, optional) – SNDMORE is handled automatically for frames before the last.
  • copy (bool, optional) – Should the frame(s) be sent in a copying or non-copying manner. If copy=False, frames smaller than self.copy_threshold bytes will be copied anyway.
  • track (bool, optional) – Should the frame(s) be tracked for notification that ZMQ has finished with it (ignored if copy=True).
Returns:

  • None (if copy or not track)
  • MessageTracker (if track and not copy) – a MessageTracker object, whose pending property will be True until the last send is completed.

send_pyobj(obj, flags=0, protocol=3, **kwargs)

send a Python object as a message using pickle to serialize

Parameters:
  • obj (Python object) – The Python object to send.
  • flags (int) – Any valid send flag.
  • protocol (int) – The pickle protocol number to use. The default is pickle.DEFAULT_PROTOCOL where defined, and pickle.HIGHEST_PROTOCOL elsewhere.
send_serialized(msg, serialize, flags=0, copy=True, **kwargs)

Send a message with a custom serialization function.

New in version 17.

Parameters:
  • msg (The message to be sent. Can be any object serializable by serialize.) –
  • serialize (callable) – The serialization function to use. serialize(msg) should return an iterable of sendable message frames (e.g. bytes objects), which will be passed to send_multipart.
  • flags (int, optional) – Any valid send flag.
  • copy (bool, optional) – Whether to copy the frames.
send_string(u, flags=0, copy=True, encoding='utf-8', **kwargs)

send a Python unicode string as a message with an encoding

0MQ communicates with raw bytes, so you must encode/decode text (unicode on py2, str on py3) around 0MQ.

Parameters:
  • u (Python unicode string (unicode on py2, str on py3)) – The unicode string to send.
  • flags (int, optional) – Any valid send flag.
  • encoding (str [default: 'utf-8']) – The encoding to be used
set(option, optval)

s.set(option, optval)

Set socket options.

See the 0MQ API documentation for details on specific options.

Parameters:
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.SUBSCRIBE, UNSUBSCRIBE, IDENTITY, HWM, LINGER, FD
    
  • optval (int or bytes) – The value of the option to set.

Notes

Warning

All options other than zmq.SUBSCRIBE, zmq.UNSUBSCRIBE and zmq.LINGER only take effect for subsequent socket bind/connects.

set_hwm(value)

set the High Water Mark

On libzmq ≥ 3, this sets both SNDHWM and RCVHWM

Warning

New values only take effect for subsequent socket bind/connects.

set_string(option, optval, encoding='utf-8')

set socket options with a unicode object

This is simply a wrapper for setsockopt to protect from encoding ambiguity.

See the 0MQ documentation for details on specific options.

Parameters:
  • option (int) – The name of the option to set. Can be any of: SUBSCRIBE, UNSUBSCRIBE, IDENTITY
  • optval (unicode string (unicode on py2, str on py3)) – The value of the option to set.
  • encoding (str) – The encoding to be used, default is utf8
setsockopt

s.set(option, optval)

Set socket options.

See the 0MQ API documentation for details on specific options.

Parameters:
  • option (int) –

    The option to set. Available values will depend on your version of libzmq. Examples include:

    zmq.SUBSCRIBE, UNSUBSCRIBE, IDENTITY, HWM, LINGER, FD
    
  • optval (int or bytes) – The value of the option to set.

Notes

Warning

All options other than zmq.SUBSCRIBE, zmq.UNSUBSCRIBE and zmq.LINGER only take effect for subsequent socket bind/connects.

setsockopt_string(option, optval, encoding='utf-8')

set socket options with a unicode object

This is simply a wrapper for setsockopt to protect from encoding ambiguity.

See the 0MQ documentation for details on specific options.

Parameters:
  • option (int) – The name of the option to set. Can be any of: SUBSCRIBE, UNSUBSCRIBE, IDENTITY
  • optval (unicode string (unicode on py2, str on py3)) – The value of the option to set.
  • encoding (str) – The encoding to be used, default is utf8
classmethod shadow(address)

Shadow an existing libzmq socket

address is the integer address of the libzmq socket or an FFI pointer to it.

New in version 14.1.

subscribe(topic)

Subscribe to a topic

Only for SUB sockets.

New in version 15.3.

unbind(addr)

s.unbind(addr)

Unbind from an address (undoes a call to bind).

New in version libzmq-3.2.

New in version 13.0.

Parameters:addr (str) – The address string. This has the form ‘protocol://interface:port’, for example ‘tcp://127.0.0.1:5555’. Protocols supported are tcp, upd, pgm, inproc and ipc. If the address is unicode, it is encoded to utf-8 first.
underlying

The address of the underlying libzmq socket

unsubscribe(topic)

Unsubscribe from a topic

Only for SUB sockets.

New in version 15.3.

Frame

class zmq.Frame(data=None, track=False, copy=None, copy_threshold=zmq.COPY_THRESHOLD)

A zmq message Frame class for non-copy send/recvs.

This class is only needed if you want to do non-copying send and recvs. When you pass a string to this class, like Frame(s), the ref-count of s is increased by two: once because the Frame saves s as an instance attribute and another because a ZMQ message is created that points to the buffer of s. This second ref-count increase makes sure that s lives until all messages that use it have been sent. Once 0MQ sends all the messages and it doesn’t need the buffer of s, 0MQ will call Py_DECREF(s).

Parameters:
  • data (object, optional) – any object that provides the buffer interface will be used to construct the 0MQ message data.
  • track (bool [default: False]) – whether a MessageTracker should be created to track this object. Tracking a message has a cost at creation, because it creates a threadsafe Event object.
  • copy (bool [default: use copy_threshold]) – Whether to create a copy of the data to pass to libzmq or share the memory with libzmq. If unspecified, copy_threshold is used.
  • copy_threshold (int [default: zmq.COPY_THRESHOLD]) – If copy is unspecified, messages smaller than this many bytes will be copied and messages larger than this will be shared with libzmq.
buffer

A read-only buffer view of the message contents.

bytes

The message content as a Python bytes object.

The first time this property is accessed, a copy of the message contents is made. From then on that same copy of the message is returned.

get(option)

Get a Frame option or property.

See the 0MQ API documentation for zmq_msg_get and zmq_msg_gets for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Changed in version 14.3: add support for zmq_msg_gets (requires libzmq-4.1)

Changed in version 17.0: Added support for routing_id and group. Only available if draft API is enabled with libzmq >= 4.2.

group

The RADIO-DISH group of the message.

Requires libzmq >= 4.2 and pyzmq built with draft APIs enabled.

New in version 17.

routing_id

The CLIENT-SERVER routing id of the message.

Requires libzmq >= 4.2 and pyzmq built with draft APIs enabled.

New in version 17.

set(option, value)

Set a Frame option.

See the 0MQ API documentation for zmq_msg_set for details on specific options.

New in version libzmq-3.2.

New in version 13.0.

Changed in version 17.0: Added support for routing_id and group. Only available if draft API is enabled with libzmq >= 4.2.

MessageTracker

class zmq.MessageTracker(*towatch)

A class for tracking if 0MQ is done using one or more messages.

When you send a 0MQ message, it is not sent immediately. The 0MQ IO thread sends the message at some later time. Often you want to know when 0MQ has actually sent the message though. This is complicated by the fact that a single 0MQ message can be sent multiple times using different sockets. This class allows you to track all of the 0MQ usages of a message.

Parameters:towatch (Event, MessageTracker, Message instances.) – This objects to track. This class can track the low-level Events used by the Message class, other MessageTrackers or actual Messages.
done

Is 0MQ completely done with the message(s) being tracked?

wait(timeout=-1)

mt.wait(timeout=-1)

Wait for 0MQ to be done with the message or until timeout.

Parameters:timeout (float [default: -1, wait forever]) – Maximum time in (s) to wait before raising NotDone.
Returns:if done before timeout
Return type:None
Raises:NotDone – if timeout reached before I am done.

Polling

Poller

class zmq.Poller

A stateful poll interface that mirrors Python’s built-in poll.

modify(socket, flags=3)

Modify the flags for an already registered 0MQ socket or native fd.

poll(timeout=None)

Poll the registered 0MQ or native fds for I/O.

Parameters:timeout (float, int) – The timeout in milliseconds. If None, no timeout (infinite). This is in milliseconds to be compatible with select.poll().
Returns:events – The list of events that are ready to be processed. This is a list of tuples of the form (socket, event), where the 0MQ Socket or integer fd is the first element, and the poll event mask (POLLIN, POLLOUT) is the second. It is common to call events = dict(poller.poll()), which turns the list of tuples into a mapping of socket : event.
Return type:list of tuples
register(socket, flags=POLLIN|POLLOUT)

p.register(socket, flags=POLLIN|POLLOUT)

Register a 0MQ socket or native fd for I/O monitoring.

register(s,0) is equivalent to unregister(s).

Parameters:
  • socket (zmq.Socket or native socket) – A zmq.Socket or any Python object having a fileno() method that returns a valid file descriptor.
  • flags (int) – The events to watch for. Can be POLLIN, POLLOUT or POLLIN|POLLOUT. If flags=0, socket will be unregistered.
unregister(socket)

Remove a 0MQ socket or native fd for I/O monitoring.

Parameters:socket (Socket) – The socket instance to stop polling.
zmq.select(rlist, wlist, xlist, timeout=None) -> (rlist, wlist, xlist)

Return the result of poll as a lists of sockets ready for r/w/exception.

This has the same interface as Python’s built-in select.select() function.

Parameters:
  • timeout (float, int, optional) – The timeout in seconds. If None, no timeout (infinite). This is in seconds to be compatible with select.select().
  • rlist (list of sockets/FDs) – sockets/FDs to be polled for read events
  • wlist (list of sockets/FDs) – sockets/FDs to be polled for write events
  • xlist (list of sockets/FDs) – sockets/FDs to be polled for error events
Returns:

(rlist, wlist, xlist) – Lists correspond to sockets available for read/write/error events respectively.

Return type:

tuple of lists of sockets (length 3)

Exceptions

ZMQError

class zmq.ZMQError(errno=None, msg=None)

Wrap an errno style error.

Parameters:
  • errno (int) – The ZMQ errno or None. If None, then zmq_errno() is called and used.
  • msg (string) – Description of the error or None.
with_traceback()

Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

ZMQVersionError

class zmq.ZMQVersionError(min_version, msg='Feature')

Raised when a feature is not provided by the linked version of libzmq.

New in version 14.2.

with_traceback()

Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

Again

class zmq.Again(errno='ignored', msg='ignored')

Wrapper for zmq.EAGAIN

New in version 13.0.

ContextTerminated

class zmq.ContextTerminated(errno='ignored', msg='ignored')

Wrapper for zmq.ETERM

New in version 13.0.

NotDone

class zmq.NotDone

Raised when timeout is reached while waiting for 0MQ to finish with a Message

See also

MessageTracker.wait
object for tracking when ZeroMQ is done

ZMQBindError

class zmq.ZMQBindError

An error for Socket.bind_to_random_port().

See also

Socket.bind_to_random_port

Functions

zmq.zmq_version()

return the version of libzmq as a string

zmq.pyzmq_version()

return the version of pyzmq as a string

zmq.zmq_version_info()

Return the version of ZeroMQ itself as a 3-tuple of ints.

zmq.pyzmq_version_info()

return the pyzmq version as a tuple of at least three numbers

If pyzmq is a development version, inf will be appended after the third integer.

zmq.has()

Check for zmq capability by name (e.g. ‘ipc’, ‘curve’)

New in version libzmq-4.1.

New in version 14.1.

zmq.device(device_type, frontend, backend)

Start a zeromq device.

Deprecated since version libzmq-3.2: Use zmq.proxy

Parameters:
  • device_type ((QUEUE, FORWARDER, STREAMER)) – The type of device to start.
  • frontend (Socket) – The Socket instance for the incoming traffic.
  • backend (Socket) – The Socket instance for the outbound traffic.
zmq.proxy(frontend, backend, capture)

Start a zeromq proxy (replacement for device).

New in version libzmq-3.2.

New in version 13.0.

Parameters:
  • frontend (Socket) – The Socket instance for the incoming traffic.
  • backend (Socket) – The Socket instance for the outbound traffic.
  • capture (Socket (optional)) – The Socket instance for capturing traffic.
zmq.curve_keypair()

generate a Z85 keypair for use with zmq.CURVE security

Requires libzmq (≥ 4.0) to have been built with CURVE support.

New in version libzmq-4.0.

New in version 14.0.

Returns:(public, secret) – The public and private keypair as 40 byte z85-encoded bytestrings.
Return type:two bytestrings
zmq.get_includes()

Return a list of directories to include for linking against pyzmq with cython.

zmq.get_library_dirs()

Return a list of directories used to link against pyzmq’s bundled libzmq.