zmq_setsockopt.txt 46 KB
Newer Older
1 2 3 4 5 6 7
zmq_setsockopt(3)
=================


NAME
----

Martin Lucina's avatar
Martin Lucina committed
8
zmq_setsockopt - set 0MQ socket options
9 10 11 12


SYNOPSIS
--------
Martin Lucina's avatar
Martin Lucina committed
13
*int zmq_setsockopt (void '*socket', int 'option_name', const void '*option_value', size_t 'option_len');*
14

Kobolog's avatar
Kobolog committed
15
Caution: All options, with the exception of ZMQ_SUBSCRIBE, ZMQ_UNSUBSCRIBE,
16
ZMQ_LINGER, ZMQ_ROUTER_HANDOVER, ZMQ_ROUTER_MANDATORY, ZMQ_PROBE_ROUTER,
17 18 19
ZMQ_XPUB_VERBOSE, ZMQ_XPUB_VERBOSE_UNSUBSCRIBE, ZMQ_REQ_CORRELATE,
ZMQ_REQ_RELAXED, ZMQ_SNDHWM and ZMQ_RCVHWM, only take effect for
subsequent socket bind/connects.
Pieter Hintjens's avatar
Pieter Hintjens committed
20 21 22

Specifically, security options take effect for subsequent bind/connect calls,
and can be changed at any time to affect subsequent binds and/or connects.
23 24 25

DESCRIPTION
-----------
Martin Lucina's avatar
Martin Lucina committed
26 27 28 29 30
The _zmq_setsockopt()_ function shall set the option specified by the
'option_name' argument to the value pointed to by the 'option_value' argument
for the 0MQ socket pointed to by the 'socket' argument. The 'option_len'
argument is the size of the option value in bytes.

Martin Lucina's avatar
Martin Lucina committed
31
The following socket options can be set with the _zmq_setsockopt()_ function:
Martin Lucina's avatar
Martin Lucina committed
32 33 34 35


ZMQ_AFFINITY: Set I/O thread affinity
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Martin Lucina's avatar
Martin Lucina committed
36 37
The 'ZMQ_AFFINITY' option shall set the I/O thread affinity for newly created
connections on the specified 'socket'.
Martin Lucina's avatar
Martin Lucina committed
38

39 40 41 42 43 44 45
Affinity determines which threads from the 0MQ I/O thread pool associated with
the socket's _context_ shall handle newly created connections.  A value of zero
specifies no affinity, meaning that work shall be distributed fairly among all
0MQ I/O threads in the thread pool. For non-zero values, the lowest bit
corresponds to thread 1, second lowest bit to thread 2 and so on.  For example,
a value of 3 specifies that subsequent connections on 'socket' shall be handled
exclusively by I/O threads 1 and 2.
Martin Lucina's avatar
Martin Lucina committed
46 47 48 49

See also linkzmq:zmq_init[3] for details on allocating the number of I/O
threads for a specific _context_.

50
[horizontal]
51
Option value type:: uint64_t
Martin Lucina's avatar
Martin Lucina committed
52 53 54 55 56
Option value unit:: N/A (bitmap)
Default value:: 0
Applicable socket types:: N/A


57 58 59 60 61 62
ZMQ_BACKLOG: Set maximum length of the queue of outstanding connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_BACKLOG' option shall set the maximum length of the queue of
outstanding peer connections for the specified 'socket'; this only applies to
connection-oriented transports. For details refer to your operating system
documentation for the 'listen' function.
Martin Lucina's avatar
Martin Lucina committed
63

64 65 66 67 68 69 70
[horizontal]
Option value type:: int
Option value unit:: connections
Default value:: 100
Applicable socket types:: all, only for connection-oriented transports.


71 72 73 74 75 76
ZMQ_CONNECT_RID: Assign the next outbound connection id 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_CONNECT_RID' option sets the peer id of the next host connected 
via the zmq_connect() call, and immediately readies that connection for 
data transfer with the named id.  This option applies only to the first
subsequent call to zmq_connect(), calls thereafter use default connection 
77
behaviour. 
78

79 80 81
Typical use is to set this socket option ahead of each zmq_connect() attempt 
to a new host. Each connection MUST be assigned a unique name. Assigning a 
name that is already in use is not allowed. 
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

Useful when connecting ROUTER to ROUTER, or STREAM to STREAM, as it 
allows for immediate sending to peers. Outbound id framing requirements 
for ROUTER and STREAM sockets apply.

The peer id should be from 1 to 255 bytes long and MAY NOT start with 
binary zero.

[horizontal]
Option value type:: binary data
Option value unit:: N/A
Default value:: NULL
Applicable socket types:: ZMQ_ROUTER, ZMQ_STREAM


97 98 99 100
ZMQ_CONFLATE: Keep only last message
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If set, a socket shall keep only one message in its inbound/outbound
queue, this message being the last message received/the last message
101
to be sent. Ignores 'ZMQ_RCVHWM' and 'ZMQ_SNDHWM' options. Does not
102 103
support multi-part messages, in particular, only one part of it is kept
in the socket internal queue.
Martin Lucina's avatar
Martin Lucina committed
104

105
[horizontal]
106 107 108 109
Option value type:: int
Option value unit:: boolean
Default value:: 0 (false)
Applicable socket types:: ZMQ_PULL, ZMQ_PUSH, ZMQ_SUB, ZMQ_PUB, ZMQ_DEALER
Martin Lucina's avatar
Martin Lucina committed
110 111


KIU Shueng Chuan's avatar
KIU Shueng Chuan committed
112 113 114 115 116 117 118 119 120 121 122 123 124 125
ZMQ_CONNECT_TIMEOUT: Set 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.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: 0 (disabled)
Applicable socket types:: all, when using TCP transports.


126 127 128 129
ZMQ_CURVE_PUBLICKEY: Set CURVE public key
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the socket's long term public key. You must set this on CURVE client
sockets, see linkzmq:zmq_curve[7]. You can provide the key as 32 binary
130 131 132 133 134 135 136
bytes, or as a 40-character string encoded in the Z85 encoding format and
terminated in a null byte. The public key must always be used with the
matching secret key. To generate a public/secret key pair, use
linkzmq:zmq_curve_keypair[3].

NOTE: an option value size of 40 is supported for backwards compatibility,
though is deprecated.
Martin Lucina's avatar
Martin Lucina committed
137

138
[horizontal]
139
Option value type:: binary data or Z85 text string
140
Option value size:: 32 or 41
141 142 143 144 145 146 147 148 149
Default value:: NULL
Applicable socket types:: all, when using TCP transport


ZMQ_CURVE_SECRETKEY: Set CURVE secret key
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the socket's long term secret key. You must set this on both CURVE
client and server sockets, see linkzmq:zmq_curve[7]. You can provide the
key as 32 binary bytes, or as a 40-character string encoded in the Z85
150 151 152 153 154
encoding format and terminated in a null byte. To generate a public/secret
key pair, use linkzmq:zmq_curve_keypair[3].

NOTE: an option value size of 40 is supported for backwards compatibility,
though is deprecated.
155 156 157

[horizontal]
Option value type:: binary data or Z85 text string
158
Option value size:: 32 or 41
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184
Default value:: NULL
Applicable socket types:: all, when using TCP transport


ZMQ_CURVE_SERVER: Set CURVE server role
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Defines whether the socket will act as server for CURVE security, see
linkzmq:zmq_curve[7]. A value of '1' means the socket will act as
CURVE server. A value of '0' means the socket will not act as CURVE
server, and its security role then depends on other option settings.
Setting this to '0' shall reset the socket security to NULL. When you
set this you must also set the server's secret key using the
ZMQ_CURVE_SECRETKEY option. A server socket does not need to know
its own public key.

[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: all, when using TCP transport


ZMQ_CURVE_SERVERKEY: Set CURVE server key
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the socket's long term server key. You must set this on CURVE client
sockets, see linkzmq:zmq_curve[7]. You can provide the key as 32 binary
185 186 187 188 189 190 191
bytes, or as a 40-character string encoded in the Z85 encoding format and
terminated in a null byte. This key must have been generated together with
the server's secret key. To generate a public/secret key pair, use
linkzmq:zmq_curve_keypair[3].

NOTE: an option value size of 40 is supported for backwards compatibility,
though is deprecated.
192 193 194

[horizontal]
Option value type:: binary data or Z85 text string
195
Option value size:: 32 or 41
196 197
Default value:: NULL
Applicable socket types:: all, when using TCP transport
Martin Lucina's avatar
Martin Lucina committed
198 199


200 201 202 203 204 205 206 207 208 209 210 211 212 213 214
ZMQ_GSSAPI_PLAINTEXT: Disable GSSAPI encryption
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Defines whether communications on the socket will encrypted, see
linkzmq:zmq_gssapi[7]. A value of '1' means  that communications will be
plaintext.  A value of '0' means communications will be encrypted.

[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0 (false)
Applicable socket types:: all, when using TCP transport


ZMQ_GSSAPI_PRINCIPAL: Set name of GSSAPI principal
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
J.T. Conklin's avatar
J.T. Conklin committed
215
Sets the name of the principal for whom GSSAPI credentials should be acquired.
216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238

[horizontal]
Option value type:: character string
Option value unit:: N/A
Default value:: not set
Applicable socket types:: all, when using TCP transport


ZMQ_GSSAPI_SERVER: Set GSSAPI server role
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Defines whether the socket will act as server for GSSAPI security, see
linkzmq:zmq_gssapi[7]. A value of '1' means the socket will act as GSSAPI
server. A value of '0' means the socket will act as GSSAPI client.

[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0 (false)
Applicable socket types:: all, when using TCP transport


ZMQ_GSSAPI_SERVICE_PRINCIPAL: Set name of GSSAPI service principal
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
J.T. Conklin's avatar
J.T. Conklin committed
239
Sets the name of the principal of the GSSAPI server to which a GSSAPI client
240 241 242 243 244 245 246 247 248
intends to connect.

[horizontal]
Option value type:: character string
Option value unit:: N/A
Default value:: not set
Applicable socket types:: all, when using TCP transport


249 250 251 252 253 254 255 256 257 258 259 260 261 262 263
ZMQ_HANDSHAKE_IVL: Set maximum handshake interval
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_HANDSHAKE_IVL' option shall set the maximum handshake interval for
the specified 'socket'. 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.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: 30000
Applicable socket types:: all but ZMQ_STREAM, only for connection-oriented transports

264

265 266 267 268 269 270 271 272 273 274 275 276
ZMQ_HEARTBEAT_IVL: Set interval between sending ZMTP heartbeats
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_HEARTBEAT_IVL' option shall set the interval between sending ZMTP heartbeats
for the specified 'socket'. If this option is set and is greater than 0, then a 'PING'
ZMTP command will be sent every 'ZMQ_HEARTBEAT_IVL' milliseconds.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: 0
Applicable socket types:: all, when using connection-oriented transports

277

278 279 280 281 282 283 284 285 286 287 288 289 290 291 292
ZMQ_HEARTBEAT_TIMEOUT: Set timeout for ZMTP heartbeats
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_HEARTBEAT_TIMEOUT' option shall set how long to wait before timing-out a
connection after sending a 'PING' ZMTP command and not receiving any traffic. This
option is only valid if 'ZMQ_HEARTBEAT_IVL' is also set, and is greater than 0. The
connection will time out if there is no traffic received after sending the 'PING'
command, but the received traffic does not have to be a 'PONG' command - any received
traffic will cancel the timeout.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: 0
Applicable socket types:: all, when using connection-oriented transports

293

294 295 296 297 298
ZMQ_HEARTBEAT_TTL: Set the TTL value for ZMTP heartbeats
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_HEARTBEAT_TTL' option shall set the timeout 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
299 300 301
does not have any effect if 'ZMQ_HEARTBEAT_IVL' is not set or is 0. Internally, this
value is rounded down to the nearest decisecond, any value less than 100 will have
no effect.
302 303

[horizontal]
304 305
Option value type:: int
Option value unit:: milliseconds
306 307
Default value:: 0
Applicable socket types:: all, when using connection-oriented transports
308

309

310 311
ZMQ_IDENTITY: Set socket identity
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Pieter Hintjens's avatar
Pieter Hintjens committed
312 313
The 'ZMQ_IDENTITY' option shall set the identity of the specified 'socket'
when connecting to a ROUTER socket. The identity should be from 1 to 255
314
bytes long and may contain any values.
315

Pieter Hintjens's avatar
Pieter Hintjens committed
316 317 318 319 320 321
If two clients use the same identity when connecting to a ROUTER, the
results shall depend on the ZMQ_ROUTER_HANDOVER option setting. If that
is not set (or set to the default of zero), the ROUTER socket shall reject
clients trying to connect with an already-used identity. If that option
is set to 1, the ROUTER socket shall hand-over the connection to the new
client and disconnect the existing one.
Pieter Hintjens's avatar
Pieter Hintjens committed
322

323 324 325 326
[horizontal]
Option value type:: binary data
Option value unit:: N/A
Default value:: NULL
327
Applicable socket types:: ZMQ_REQ, ZMQ_REP, ZMQ_ROUTER, ZMQ_DEALER.
328 329


330 331 332 333 334 335 336 337
ZMQ_IMMEDIATE: Queue messages only to completed connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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 (REQ, PUSH, DEALER). If this option is set to `1`, 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.
Martin Lucina's avatar
Martin Lucina committed
338

339
[horizontal]
340
Option value type:: int
341 342 343
Option value unit:: boolean
Default value:: 0 (false)
Applicable socket types:: all, only for connection-oriented transports.
Martin Lucina's avatar
Martin Lucina committed
344 345


346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367
ZMQ_INVERT_MATCHING: Invert message filtering
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reverses the filtering behavior of PUB-SUB sockets, when set to 1.

On 'PUB' and 'XPUB' sockets, this causes messages to be sent to all
connected sockets 'except' those subscribed to a prefix that matches
the message. On 'SUB' sockets, this causes only incoming messages that
do 'not' match any of the socket's subscriptions to be received by the user.

Whenever 'ZMQ_INVERT_MATCHING' is set to 1 on a 'PUB' socket, all 'SUB'
sockets connecting to it must also have the option set to 1. Failure to
do so will have the 'SUB' sockets reject everything the 'PUB' socket sends
them. 'XSUB' sockets do not need to do this because they do not filter
incoming messages.

[horizontal]
Option value type:: int
Option value unit:: 0,1
Default value:: 0
Applicable socket types:: ZMQ_PUB, ZMQ_XPUB, ZMQ_SUB


368 369 370 371 372 373
ZMQ_IPV6: Enable IPv6 on socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Set the IPv6 option for the socket. A value of `1` means IPv6 is
enabled on the socket, while `0` means the socket will use only IPv4.
When IPv6 is enabled the socket will connect to, or accept connections
from, both IPv4 and IPv6 hosts.
Martin Lucina's avatar
Martin Lucina committed
374

375
[horizontal]
376
Option value type:: int
377 378 379
Option value unit:: boolean
Default value:: 0 (false)
Applicable socket types:: all, when using TCP transports.
380

381

382 383
ZMQ_LINGER: Set linger period for socket shutdown
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
384 385
The 'ZMQ_LINGER' option shall set the linger period for the specified 'socket'.
The linger period determines how long pending messages which have yet to be
386 387 388 389
sent to a peer shall linger in memory after a socket is disconnected with
linkzmq:zmq_disconnect[3] or closed with linkzmq:zmq_close[3], and further
affects the termination of the socket's context with linkzmq:zmq_term[3]. The
following outlines the different behaviours:
390

391
* A value of '-1' specifies an infinite linger period. Pending
392 393 394
  messages shall not be discarded after a call to _zmq_disconnect()_ or
  _zmq_close()_; attempting to terminate the socket's context with _zmq_term()_
  shall block until all pending messages have been sent to a peer.
395 396

* The value of '0' specifies no linger period. Pending messages shall be
397
  discarded immediately after a call to _zmq_disconnect()_ or _zmq_close()_.
398 399

* Positive values specify an upper bound for the linger period in milliseconds.
400 401 402 403
  Pending messages shall not be discarded after a call to _zmq_disconnect()_ or
  _zmq_close()_; attempting to terminate the socket's context with _zmq_term()_
  shall block until either all pending messages have been sent to a peer, or the
  linger period expires, after which any pending messages shall be discarded.
404 405 406 407

[horizontal]
Option value type:: int
Option value unit:: milliseconds
408
Default value:: 30000 (thirty seconds)
409 410 411
Applicable socket types:: all


412 413 414 415 416 417 418 419 420 421
ZMQ_MAXMSGSIZE: Maximum acceptable inbound message size
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Limits the size of the inbound message. If a peer sends a message larger than
ZMQ_MAXMSGSIZE it is disconnected. Value of -1 means 'no limit'.

[horizontal]
Option value type:: int64_t
Option value unit:: bytes
Default value:: -1
Applicable socket types:: all
422

423 424 425 426 427 428

ZMQ_MULTICAST_HOPS: Maximum network hops for multicast packets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
429 430 431

[horizontal]
Option value type:: int
432 433 434
Option value unit:: network hops
Default value:: 1
Applicable socket types:: all, when using multicast transports
435 436


437 438 439 440 441 442 443 444 445 446 447 448 449 450 451
ZMQ_MULTICAST_MAXTPDU: Maximum transport data unit size for multicast packets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.

[horizontal]
Option value type:: int
Option value unit:: bytes
Default value:: 1500
Applicable socket types:: all, when using multicast transports


452 453 454 455 456 457
ZMQ_PLAIN_PASSWORD: Set PLAIN security 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, see linkzmq:zmq_plain[7]. If you set this to a null value, the security
mechanism used for connections shall be NULL, see linkzmq:zmq_null[3].
458

459 460 461 462 463 464 465 466 467 468 469 470 471 472
[horizontal]
Option value type:: character string
Option value unit:: N/A
Default value:: not set
Applicable socket types:: all, when using TCP transport


ZMQ_PLAIN_SERVER: Set PLAIN server role
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Defines whether the socket will act as server for PLAIN security, see
linkzmq:zmq_plain[7]. A value of '1' means the socket will act as
PLAIN server. A value of '0' means the socket will not act as PLAIN
server, and its security role then depends on other option settings.
Setting this to '0' shall reset the socket security to NULL.
473 474 475

[horizontal]
Option value type:: int
476 477 478
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: all, when using TCP transport
479 480


481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504
ZMQ_PLAIN_USERNAME: Set PLAIN security 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, see linkzmq:zmq_plain[7]. If you set this to a null value, the security
mechanism used for connections shall be NULL, see linkzmq:zmq_null[3].

[horizontal]
Option value type:: character string
Option value unit:: N/A
Default value:: not set
Applicable socket types:: all, when using TCP transport


ZMQ_PROBE_ROUTER: bootstrap connections to ROUTER sockets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
When set to 1, the socket will automatically send an empty message when a
new connection is made or accepted. You may set this on REQ, DEALER, or
ROUTER sockets connected to a ROUTER socket. The application must filter
such empty messages. The ZMQ_PROBE_ROUTER option in effect provides the
ROUTER application with an event signaling the arrival of a new peer.

NOTE: do not set this option on a socket that talks to any other socket
types: the results are undefined.
505 506 507

[horizontal]
Option value type:: int
508 509 510
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_ROUTER, ZMQ_DEALER, ZMQ_REQ
511

512

513 514 515 516 517 518 519 520 521 522
ZMQ_RATE: Set multicast data rate
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RATE' option shall set the maximum send or receive data rate for
multicast transports such as linkzmq:zmq_pgm[7] using the specified 'socket'.

[horizontal]
Option value type:: int
Option value unit:: kilobits per second
Default value:: 100
Applicable socket types:: all, when using multicast transports
523

524 525 526 527

ZMQ_RCVBUF: Set kernel receive buffer size
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RCVBUF' option shall set the underlying kernel receive buffer size for
528
the 'socket' to the specified size in bytes.  A value of -1 means leave the
529 530
OS default unchanged. For details refer to your operating system documentation
for the 'SO_RCVBUF' socket option.
531 532

[horizontal]
533
Option value type:: int
534
Option value unit:: bytes
535
Default value:: -1
536 537
Applicable socket types:: all

538

539 540 541 542 543 544 545
ZMQ_RCVHWM: Set high water mark for inbound messages
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RCVHWM' option shall set the high water mark for inbound messages on
the specified 'socket'. The high water mark is a hard limit on the maximum
number of outstanding messages 0MQ shall queue in memory for any single peer
that the specified 'socket' is communicating with. A value of zero means no
limit.
546

547 548 549 550 551
If this limit has been reached the socket shall enter an exceptional state and
depending on the socket type, 0MQ shall take appropriate action such as
blocking or dropping sent messages. Refer to the individual socket descriptions
in linkzmq:zmq_socket[3] for details on the exact action taken for each socket
type.
552 553 554

[horizontal]
Option value type:: int
555 556 557
Option value unit:: messages
Default value:: 1000
Applicable socket types:: all
558

559

560 561 562 563 564 565 566 567 568 569 570 571 572 573 574
ZMQ_RCVTIMEO: Maximum time before a recv operation returns with EAGAIN
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the timeout for receive operation on the socket. If the value is `0`,
_zmq_recv(3)_ will return immediately, with a EAGAIN error if there is no
message to receive. If the value is `-1`, it will block until a message is
available. For all other values, it will wait for a message for that amount
of time before returning with an EAGAIN error.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: -1 (infinite)
Applicable socket types:: all


575 576 577 578 579 580
ZMQ_RECONNECT_IVL: Set reconnection interval
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RECONNECT_IVL' option shall set the initial reconnection interval for
the specified 'socket'.  The reconnection interval is the period 0MQ
shall wait between attempts to reconnect disconnected peers when using
connection-oriented transports. The value -1 means no reconnection.
581

582 583
NOTE: The reconnection interval may be randomized by 0MQ to prevent
reconnection storms in topologies with a large number of peers per socket.
584 585 586 587

[horizontal]
Option value type:: int
Option value unit:: milliseconds
588 589
Default value:: 100
Applicable socket types:: all, only for connection-oriented transports
590 591


592 593 594 595 596 597 598 599
ZMQ_RECONNECT_IVL_MAX: Set maximum reconnection interval
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RECONNECT_IVL_MAX' option shall set the maximum reconnection interval
for the specified 'socket'.  This is the maximum period 0MQ shall wait between
attempts to reconnect. On each reconnect attempt, the previous interval shall be
doubled untill ZMQ_RECONNECT_IVL_MAX is reached. This allows for exponential
backoff strategy. Default value means no exponential backoff is performed and
reconnect interval calculations are only based on ZMQ_RECONNECT_IVL.
Steven McCoy's avatar
Steven McCoy committed
600

601
NOTE:  Values less than ZMQ_RECONNECT_IVL will be ignored.
Pieter Hintjens's avatar
Pieter Hintjens committed
602 603 604

[horizontal]
Option value type:: int
605 606 607
Option value unit:: milliseconds
Default value:: 0 (only use ZMQ_RECONNECT_IVL)
Applicable socket types:: all, only for connection-oriented transports
Pieter Hintjens's avatar
Pieter Hintjens committed
608 609


610 611 612 613 614 615
ZMQ_RECOVERY_IVL: Set multicast recovery interval
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_RECOVERY_IVL' option shall set the recovery interval for multicast
transports using the specified 'socket'. The recovery interval determines the
maximum time in milliseconds that a receiver can be absent from a multicast
group before unrecoverable data loss will occur.
Pieter Hintjens's avatar
Pieter Hintjens committed
616

617 618 619
CAUTION: Exercise care when setting large recovery intervals as the data
needed for recovery will be held in memory. For example, a 1 minute recovery
interval at a data rate of 1Gbps requires a 7GB in-memory buffer.
Steven McCoy's avatar
Steven McCoy committed
620 621 622

[horizontal]
Option value type:: int
623 624 625
Option value unit:: milliseconds
Default value:: 10000
Applicable socket types:: all, when using multicast transports
Steven McCoy's avatar
Steven McCoy committed
626 627


628 629
ZMQ_REQ_CORRELATE: match replies with requests
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
630
The default behaviour of REQ sockets is to rely on the ordering of messages to
631 632 633 634 635
match requests and responses and that is usually sufficient. When this option
is set to 1, the REQ socket will prefix outgoing messages with an extra frame
containing a request id. That means the full message is (request id, 0,
user frames...). The REQ socket will discard all incoming messages that don't
begin with these two frames.
636 637 638

[horizontal]
Option value type:: int
639
Option value unit:: 0, 1
640
Default value:: 0
641
Applicable socket types:: ZMQ_REQ
642 643


644 645 646 647 648 649 650 651 652
ZMQ_REQ_RELAXED: relax strict alternation between request and reply
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By default, a REQ socket does not allow initiating a new request with
_zmq_send(3)_ until the reply to the previous one has been received.
When set to 1, sending another message is allowed and has the effect of
disconnecting the underlying connection to the peer from which the reply was
expected, triggering a reconnection attempt on transports that support it.
The request-reply state machine is reset and a new request is sent to the
next available peer.
653

654 655 656
If set to 1, also enable ZMQ_REQ_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.
657 658 659

[horizontal]
Option value type:: int
660 661 662
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_REQ
663

664

Pieter Hintjens's avatar
Pieter Hintjens committed
665 666 667 668 669 670 671 672
ZMQ_ROUTER_HANDOVER: handle duplicate client identities on ROUTER sockets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If two clients use the same identity when connecting to a ROUTER, the
results shall depend on the ZMQ_ROUTER_HANDOVER option setting. If that
is not set (or set to the default of zero), the ROUTER socket shall reject
clients trying to connect with an already-used identity. If that option
is set to 1, the ROUTER socket shall hand-over the connection to the new
client and disconnect the existing one.
673

Pieter Hintjens's avatar
Pieter Hintjens committed
674
[horizontal]
675 676 677 678 679
Option value type:: int
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_ROUTER

680

681 682
ZMQ_ROUTER_MANDATORY: accept only routable messages on ROUTER sockets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
683
Sets the ROUTER socket behaviour when an unroutable message is encountered. A
684
value of `0` is the default and discards the message silently when it cannot be
685 686 687 688 689
routed or the peers SNDHWM is reached.  A value of `1` returns an
'EHOSTUNREACH' error code if the message cannot be routed or 'EAGAIN' error
code if the SNDHWM is reached and ZMQ_DONTWAIT was used. Without ZMQ_DONTWAIT
it will block until the SNDTIMEO is reached or a spot in the send queue opens
up.
690

Kobolog's avatar
Kobolog committed
691 692
[horizontal]
Option value type:: int
693 694
Option value unit:: 0, 1
Default value:: 0
Kobolog's avatar
Kobolog committed
695 696 697
Applicable socket types:: ZMQ_ROUTER


698 699
ZMQ_ROUTER_RAW: switch ROUTER socket to raw mode
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Pieter Hintjens's avatar
Pieter Hintjens committed
700
Sets the raw mode on the ROUTER, when set to 1. When the ROUTER socket is in
701 702
raw mode, and when using the tcp:// transport, it will read and write TCP data
without 0MQ framing. This lets 0MQ applications talk to non-0MQ applications.
703
When using raw mode, you cannot set explicit identities, and the ZMQ_SNDMORE
704 705 706
flag is ignored when sending data messages. In raw mode you can close a specific
connection by sending it a zero-length message (following the identity frame).

707 708
NOTE: This option is deprecated, please use ZMQ_STREAM sockets instead.

709 710 711 712 713 714 715
[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_ROUTER


716 717 718
ZMQ_SNDBUF: Set kernel transmit buffer size
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_SNDBUF' option shall set the underlying kernel transmit buffer size
719
for the 'socket' to the specified size in bytes.  A value of -1 means leave
720 721
the OS default unchanged. For details please refer to your operating system
documentation for the 'SO_SNDBUF' socket option.
722 723 724

[horizontal]
Option value type:: int
725
Option value unit:: bytes
726
Default value:: -1
727
Applicable socket types:: all
728 729


730 731 732 733 734 735 736
ZMQ_SNDHWM: Set high water mark for outbound messages
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_SNDHWM' option shall set the high water mark for outbound messages on
the specified 'socket'. The high water mark is a hard limit on the maximum
number of outstanding messages 0MQ shall queue in memory for any single peer
that the specified 'socket' is communicating with. A value of zero means no
limit.
737

738 739 740 741 742
If this limit has been reached the socket shall enter an exceptional state and
depending on the socket type, 0MQ shall take appropriate action such as
blocking or dropping sent messages. Refer to the individual socket descriptions
in linkzmq:zmq_socket[3] for details on the exact action taken for each socket
type.
743

744 745 746
NOTE: 0MQ does not guarantee that the socket will accept as many as ZMQ_SNDHWM
messages, and the actual limit may be as much as 60-70% lower depending on the
flow of messages on the socket.
747 748 749

[horizontal]
Option value type:: int
750 751 752
Option value unit:: messages
Default value:: 1000
Applicable socket types:: all
753

754

755 756 757 758 759 760 761
ZMQ_SNDTIMEO: Maximum time before a send operation returns with EAGAIN
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the timeout for send operation on the socket. If the value is `0`,
_zmq_send(3)_ will return immediately, with a EAGAIN error if the message
cannot be sent. If the value is `-1`, it will block until the message is sent.
For all other values, it will try to send the message for that amount of time
before returning with an EAGAIN error.
762 763 764

[horizontal]
Option value type:: int
765 766 767
Option value unit:: milliseconds
Default value:: -1 (infinite)
Applicable socket types:: all
768 769


770 771 772 773 774
ZMQ_STREAM_NOTIFY: send connect and disconnect notifications
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Enables connect and disconnect notifications on a STREAM socket, when set
to 1. When notifications are enabled, the socket delivers a zero-length
message when a peer connects or disconnects.
775 776 777 778

[horizontal]
Option value type:: int
Option value unit:: 0, 1
779
Default value:: 1
780 781 782
Applicable socket types:: ZMQ_STREAM


783 784 785 786 787
ZMQ_SUBSCRIBE: Establish message filter
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_SUBSCRIBE' option shall establish a new message filter on a 'ZMQ_SUB'
socket. Newly created 'ZMQ_SUB' sockets shall filter out all incoming messages,
therefore you should call this option to establish an initial message filter.
788

789 790 791 792 793
An empty 'option_value' of length zero shall subscribe to all incoming
messages. A non-empty 'option_value' shall subscribe to all messages beginning
with the specified prefix. Multiple filters may be attached to a single
'ZMQ_SUB' socket, in which case a message shall be accepted if it matches at
least one filter.
794 795

[horizontal]
796 797 798 799
Option value type:: binary data
Option value unit:: N/A
Default value:: N/A
Applicable socket types:: ZMQ_SUB
800 801


802 803 804 805
ZMQ_TCP_KEEPALIVE: Override SO_KEEPALIVE socket option
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Override 'SO_KEEPALIVE' socket option (where supported by OS).
The default value of `-1` means to skip any overrides and leave it to OS default.
806 807

[horizontal]
808 809 810 811
Option value type:: int
Option value unit:: -1,0,1
Default value:: -1 (leave to OS default)
Applicable socket types:: all, when using TCP transports.
812 813


814 815 816 817
ZMQ_TCP_KEEPALIVE_CNT: Override TCP_KEEPCNT socket option
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Override 'TCP_KEEPCNT' socket option (where supported by OS). The default
value of `-1` means to skip any overrides and leave it to OS default.
818 819

[horizontal]
820 821 822 823
Option value type:: int
Option value unit:: -1,>0
Default value:: -1 (leave to OS default)
Applicable socket types:: all, when using TCP transports.
824 825


826
ZMQ_TCP_KEEPALIVE_IDLE: Override TCP_KEEPIDLE (or TCP_KEEPALIVE on some OS)
827
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
828
Override 'TCP_KEEPIDLE' (or 'TCP_KEEPALIVE' on some OS) socket option (where
829 830
supported by OS). The default value of `-1` means to skip any overrides and
leave it to OS default.
831 832

[horizontal]
833 834 835 836
Option value type:: int
Option value unit:: -1,>0
Default value:: -1 (leave to OS default)
Applicable socket types:: all, when using TCP transports.
837 838


839
ZMQ_TCP_KEEPALIVE_INTVL: Override TCP_KEEPINTVL socket option
840
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
841 842
Override 'TCP_KEEPINTVL' socket option(where supported by OS). The default
value of `-1` means to skip any overrides and leave it to OS default.
843 844 845

[horizontal]
Option value type:: int
846 847 848
Option value unit:: -1,>0
Default value:: -1 (leave to OS default)
Applicable socket types:: all, when using TCP transports.
849

850

851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
ZMQ_TCP_RETRANSMIT_TIMEOUT: Set TCP Retransmit Timeout
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
On OSes where it is supported, sets how long before an unacknowledged TCP
retransmit times out.
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.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: 0 (leave to OS default)
Applicable socket types:: all, when using TCP transports.


867 868 869 870 871
ZMQ_TOS: Set the Type-of-Service on socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the ToS fields (Differentiated services (DS) and Explicit Congestion
Notification (ECN) field of the IP header. The ToS field is typically used
to specify a packets priority. The availability of this option is dependent
J.T. Conklin's avatar
J.T. Conklin committed
872
on intermediate network equipment that inspect the ToS field and provide a
873
path for low-delay, high-throughput, highly-reliable service, etc.
874 875 876

[horizontal]
Option value type:: int
877
Option value unit:: >0
878
Default value:: 0
879
Applicable socket types:: all, only for connection-oriented transports
880 881


882 883 884 885 886 887 888
ZMQ_UNSUBSCRIBE: Remove message filter
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The 'ZMQ_UNSUBSCRIBE' option shall remove an existing message filter on a
'ZMQ_SUB' socket. The filter specified must match an existing filter previously
established with the 'ZMQ_SUBSCRIBE' option. If the socket has several
instances of the same filter attached the 'ZMQ_UNSUBSCRIBE' option shall remove
only one instance, leaving the rest in place and functional.
889 890

[horizontal]
891
Option value type:: binary data
892
Option value unit:: N/A
893 894
Default value:: N/A
Applicable socket types:: ZMQ_SUB
895 896


897 898
ZMQ_XPUB_VERBOSE: provide all subscription messages on XPUB sockets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
899
Sets the 'XPUB' socket behaviour on new subscriptions and unsubscriptions.
900 901
A value of '0' is the default and passes only new subscription messages to
upstream. A value of '1' passes all subscription messages upstream.
902 903 904

[horizontal]
Option value type:: int
905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_XPUB


ZMQ_XPUB_VERBOSE_UNSUBSCRIBE: provide all unsubscription messages on XPUB sockets
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sets the 'XPUB' socket behaviour on new subscriptions and unsubscriptions.
A value of '0' is the default and passes only the last unsubscription message to
upstream. A value of '1' passes all unsubscription messages upstream.

This behaviour should be enabled in all the intermediary XPUB sockets if
ZMQ_XPUB_VERBOSE is also being used in order to allow the correct forwarding
of all the unsubscription messages.

NOTE: This behaviour only takes effect when ZMQ_XPUB_VERBOSE is also enabled.

[horizontal]
Option value type:: int
924 925
Option value unit:: 0, 1
Default value:: 0
926
Applicable socket types:: ZMQ_XPUB
927

928

929 930
ZMQ_XPUB_MANUAL: change the subscription handling to manual
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
931 932 933 934 935 936 937 938 939 940 941 942
Sets the 'XPUB' socket subscription handling mode manual/automatic.
A value of '0' is the default and subscription requests will be handled automatically.
A value of '1' will change the subscription requests handling to manual, 
with manual mode subscription requests are not added to the subscription list.
To add subscription the user need to call setsockopt with ZMQ_SUBSCRIBE on XPUB socket.

[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_XPUB

943

944 945
ZMQ_XPUB_NODROP: do not silently drop messages if SENDHWM is reached
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
946
Sets the 'XPUB' socket behaviour to return error EAGAIN if SENDHWM is
947 948 949 950 951 952 953 954 955 956 957 958
reached and the message could not be send. 

A value of `0` is the default and drops the message silently when the peers
SNDHWM is reached.  A value of `1` returns an 'EAGAIN' error code if the
SNDHWM is reached and ZMQ_DONTWAIT was used.

[horizontal]
Option value type:: int
Option value unit:: 0, 1
Default value:: 0
Applicable socket types:: ZMQ_XPUB, ZMQ_PUB

959

960 961
ZMQ_XPUB_WELCOME_MSG: set welcome message that will be received by subscriber when connecting
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
962 963 964 965 966 967 968 969 970 971 972 973
Sets a welcome message the will be recieved by subscriber when connecting.
Subscriber must subscribe to the Welcome message before connecting.
Welcome message will also be sent on reconnecting.
For welcome message to work well user must poll on incoming subscription messages on the XPUB socket and handle them.

Use NULL and lenght of zero to disable welcome message.

[horizontal]
Option value type:: binary data
Option value unit:: N/A
Default value:: NULL
Applicable socket types:: ZMQ_XPUB
974

975

976 977 978 979 980 981 982 983 984 985 986 987 988 989 990
ZMQ_ZAP_DOMAIN: Set RFC 27 authentication 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.

[horizontal]
Option value type:: character string
Option value unit:: N/A
Default value:: not set
Applicable socket types:: all, when using TCP transport


991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
ZMQ_TCP_ACCEPT_FILTER: Assign filters to allow new TCP connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Assign an arbitrary number of filters 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 call zmq_setsockopt(socket, ZMQ_TCP_ACCEPT_FILTER, NULL, 0).
Filter is a null-terminated string with ipv6 or ipv4 CIDR.

NOTE: This option is deprecated, please use authentication via the ZAP API
and IP address whitelisting / blacklisting.

[horizontal]
Option value type:: binary data
Option value unit:: N/A
Default value:: no filters (allow from all)
Applicable socket types:: all listening sockets, when using TCP transports.


ZMQ_IPC_FILTER_GID: Assign group ID filters to allow new IPC connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Assign an arbitrary number of filters that will be applied for each new IPC
transport connection on a listening socket. If no IPC filters are applied, then
the IPC transport allows connections from any process. If at least one UID,
GID, or PID filter is applied then new connection credentials should be
matched. To clear all GID filters call zmq_setsockopt(socket,
ZMQ_IPC_FILTER_GID, NULL, 0).

NOTE: GID filters are only available on platforms supporting SO_PEERCRED or
LOCAL_PEERCRED socket options (currently only Linux and later versions of
OS X).

NOTE: This option is deprecated, please use authentication via the ZAP API
and IPC whitelisting / blacklisting.

[horizontal]
Option value type:: gid_t
Option value unit:: N/A
Default value:: no filters (allow from all)
Applicable socket types:: all listening sockets, when using IPC transports.


ZMQ_IPC_FILTER_PID: Assign process ID filters to allow new IPC connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Assign an arbitrary number of filters that will be applied for each new IPC
transport connection on a listening socket. If no IPC filters are applied, then
the IPC transport allows connections from any process. If at least one UID,
GID, or PID filter is applied then new connection credentials should be
matched. To clear all PID filters call zmq_setsockopt(socket,
ZMQ_IPC_FILTER_PID, NULL, 0).

NOTE: PID filters are only available on platforms supporting the SO_PEERCRED
socket option (currently only Linux).

NOTE: This option is deprecated, please use authentication via the ZAP API
and IPC whitelisting / blacklisting.

[horizontal]
Option value type:: pid_t
Option value unit:: N/A
Default value:: no filters (allow from all)
Applicable socket types:: all listening sockets, when using IPC transports.


ZMQ_IPC_FILTER_UID: Assign user ID filters to allow new IPC connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Assign an arbitrary number of filters that will be applied for each new IPC
transport connection on a listening socket. If no IPC filters are applied, then
the IPC transport allows connections from any process. If at least one UID,
GID, or PID filter is applied then new connection credentials should be
matched. To clear all UID filters call zmq_setsockopt(socket,
ZMQ_IPC_FILTER_UID, NULL, 0).

NOTE: UID filters are only available on platforms supporting SO_PEERCRED or
LOCAL_PEERCRED socket options (currently only Linux and later versions of
OS X).

NOTE: This option is deprecated, please use authentication via the ZAP API
and IPC whitelisting / blacklisting.

[horizontal]
Option value type:: uid_t
Option value unit:: N/A
Default value:: no filters (allow from all)
Applicable socket types:: all listening sockets, when using IPC transports.


ZMQ_IPV4ONLY: Use IPv4-only on socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Set the IPv4-only option for the socket. This option is deprecated.
Please use the ZMQ_IPV6 option.

[horizontal]
Option value type:: int
Option value unit:: boolean
Default value:: 1 (true)
Applicable socket types:: all, when using TCP transports.

1089 1090
ZMQ_TCP_RECV_BUFFER: Size of the TCP receive buffer
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1091 1092 1093
The 'ZMQ_TCP_RECV_BUFFER' specifies the maximum number of bytes which can
be received by an individual syscall to receive data from the TCP socket.
The default value is 8192.
1094 1095 1096 1097


[horizontal]
Option value type:: int
1098 1099
Option value unit:: >0
Default value:: 8192
1100 1101 1102 1103
Applicable socket types:: all, when using TCP transport

ZMQ_TCP_SEND_BUFFER: Size of the TCP receive buffer
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1104 1105 1106
The 'ZMQ_TCP_SEND_BUFFER' specifies the maximum number of bytes which can
be sent by an individual syscall to transmit data to the TCP socket.
The default value is 8192.
1107 1108 1109 1110


[horizontal]
Option value type:: int
1111 1112
Option value unit:: >0
Default value:: 8192
1113
Applicable socket types:: all, when using TCP transport
1114

Ilya Kulakov's avatar
Ilya Kulakov committed
1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162
ZMQ_VMCI_BUFFER_SIZE: Set buffer size of the VMCI socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The `ZMQ_VMCI_BUFFER_SIZE` option shall set the size of the underlying
buffer for the socket. Used during negotiation before the connection is established.

[horizontal]
Option value type:: uint64_t
Option value unit:: bytes
Default value:: 65546
Applicable socket types:: all, when using VMCI transport


ZMQ_VMCI_BUFFER_MIN_SIZE: Set min buffer size of the VMCI socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The `ZMQ_VMCI_BUFFER_MIN_SIZE` option shall set the min size of the underlying
buffer for the socket. Used during negotiation before the connection is established.

[horizontal]
Option value type:: uint64_t
Option value unit:: bytes
Default value:: 128
Applicable socket types:: all, when using VMCI transport


ZMQ_VMCI_BUFFER_MAX_SIZE: Set max buffer size of the VMCI socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The `ZMQ_VMCI_BUFFER_MAX_SIZE` option shall set the max size of the underlying
buffer for the socket. Used during negotiation before the connection is established.

[horizontal]
Option value type:: uint64_t
Option value unit:: bytes
Default value:: 262144
Applicable socket types:: all, when using VMCI transport


ZMQ_VMCI_CONNECT_TIMEOUT: Set connection timeout of the VMCI socket
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The `ZMQ_VMCI_CONNECT_TIMEOUT` option shall set connection timeout
for the socket.

[horizontal]
Option value type:: int
Option value unit:: milliseconds
Default value:: -1
Applicable socket types:: all, when using VMCI transport


1163 1164
RETURN VALUE
------------
Martin Lucina's avatar
Martin Lucina committed
1165
The _zmq_setsockopt()_ function shall return zero if successful. Otherwise it
Martin Lucina's avatar
Martin Lucina committed
1166
shall return `-1` and set 'errno' to one of the values defined below.
1167 1168 1169 1170

ERRORS
------
*EINVAL*::
Martin Lucina's avatar
Martin Lucina committed
1171 1172
The requested option _option_name_ is unknown, or the requested _option_len_ or
_option_value_ is invalid.
1173
*ETERM*::
Martin Lucina's avatar
Martin Lucina committed
1174
The 0MQ 'context' associated with the specified 'socket' was terminated.
1175 1176
*ENOTSOCK*::
The provided 'socket' was invalid.
1177 1178
*EINTR*::
The operation was interrupted by delivery of a signal.
1179

1180 1181 1182

EXAMPLE
-------
Martin Lucina's avatar
Martin Lucina committed
1183
.Subscribing to messages on a 'ZMQ_SUB' socket
1184
----
Martin Lucina's avatar
Martin Lucina committed
1185 1186
/* Subscribe to all messages */
rc = zmq_setsockopt (socket, ZMQ_SUBSCRIBE, "", 0);
1187
assert (rc == 0);
Martin Lucina's avatar
Martin Lucina committed
1188 1189 1190 1191 1192 1193
/* Subscribe to messages prefixed with "ANIMALS.CATS" */
rc = zmq_setsockopt (socket, ZMQ_SUBSCRIBE, "ANIMALS.CATS", 12);
----

.Setting I/O thread affinity
----
Martin Lucina's avatar
Martin Lucina committed
1194
int64_t affinity;
Martin Lucina's avatar
Martin Lucina committed
1195
/* Incoming connections on TCP port 5555 shall be handled by I/O thread 1 */
Martin Lucina's avatar
Martin Lucina committed
1196
affinity = 1;
1197
rc = zmq_setsockopt (socket, ZMQ_AFFINITY, &affinity, sizeof (affinity));
Martin Lucina's avatar
Martin Lucina committed
1198 1199 1200 1201
assert (rc);
rc = zmq_bind (socket, "tcp://lo:5555");
assert (rc);
/* Incoming connections on TCP port 5556 shall be handled by I/O thread 2 */
Martin Lucina's avatar
Martin Lucina committed
1202
affinity = 2;
1203
rc = zmq_setsockopt (socket, ZMQ_AFFINITY, &affinity, sizeof (affinity));
Martin Lucina's avatar
Martin Lucina committed
1204
assert (rc);
1205
rc = zmq_bind (socket, "tcp://lo:5556");
Martin Lucina's avatar
Martin Lucina committed
1206
assert (rc);
1207 1208 1209 1210 1211
----


SEE ALSO
--------
Martin Lucina's avatar
Martin Lucina committed
1212
linkzmq:zmq_getsockopt[3]
1213
linkzmq:zmq_socket[3]
1214 1215
linkzmq:zmq_plain[7]
linkzmq:zmq_curve[7]
1216 1217
linkzmq:zmq[7]

1218

1219 1220
AUTHORS
-------
1221 1222
This page was written by the 0MQ community. To make a change please
read the 0MQ Contribution Policy at <http://www.zeromq.org/docs:contributing>.