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75d4f50be3
Solution: change setsockopts on printable keys to expect 41, nor 40 bytes. Code still accepts 40 bytes for compatibility, and copies the key to a well-terminated string before using it. Fixes #1148
741 lines
27 KiB
Plaintext
741 lines
27 KiB
Plaintext
zmq_getsockopt(3)
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=================
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NAME
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----
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zmq_getsockopt - get 0MQ socket options
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SYNOPSIS
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--------
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*int zmq_getsockopt (void '*socket', int 'option_name', void '*option_value', size_t '*option_len');*
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DESCRIPTION
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-----------
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The _zmq_getsockopt()_ function shall retrieve the value for the option
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specified by the 'option_name' argument for the 0MQ socket pointed to by the
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'socket' argument, and store it in the buffer pointed to by the 'option_value'
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argument. The 'option_len' argument is the size in bytes of the buffer pointed
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to by 'option_value'; upon successful completion _zmq_getsockopt()_ shall
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modify the 'option_len' argument to indicate the actual size of the option
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value stored in the buffer.
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The following options can be retrieved with the _zmq_getsockopt()_ function:
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ZMQ_AFFINITY: Retrieve I/O thread affinity
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_AFFINITY' option shall retrieve the I/O thread affinity for newly
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created connections on the specified 'socket'.
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Affinity determines which threads from the 0MQ I/O thread pool associated with
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the socket's _context_ shall handle newly created connections. A value of zero
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specifies no affinity, meaning that work shall be distributed fairly among all
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0MQ I/O threads in the thread pool. For non-zero values, the lowest bit
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corresponds to thread 1, second lowest bit to thread 2 and so on. For example,
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a value of 3 specifies that subsequent connections on 'socket' shall be handled
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exclusively by I/O threads 1 and 2.
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See also linkzmq:zmq_init[3] for details on allocating the number of I/O
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threads for a specific _context_.
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[horizontal]
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Option value type:: uint64_t
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Option value unit:: N/A (bitmap)
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Default value:: 0
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Applicable socket types:: N/A
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ZMQ_BACKLOG: Retrieve maximum length of the queue of outstanding connections
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_BACKLOG' option shall retrieve the maximum length of the queue of
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outstanding peer connections for the specified 'socket'; this only applies to
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connection-oriented transports. For details refer to your operating system
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documentation for the 'listen' function.
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[horizontal]
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Option value type:: int
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Option value unit:: connections
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Default value:: 100
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Applicable socket types:: all, only for connection-oriented transports
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ZMQ_CURVE_PUBLICKEY: Retrieve current CURVE public key
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieves the current long term public key for the socket. You can
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provide either a 32 byte buffer, to retrieve the binary key value, or
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a 41 byte buffer, to retrieve the key in a printable Z85 format.
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NOTE: to fetch a printable key, the buffer must be 41 bytes large
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to hold the 40-char key value and one null byte.
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[horizontal]
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Option value type:: binary data or Z85 text string
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Option value size:: 32 or 41
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Default value:: null
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Applicable socket types:: all, when using TCP transport
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ZMQ_CURVE_SECRETKEY: Retrieve current CURVE secret key
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieves the current long term secret key for the socket. You can
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provide either a 32 byte buffer, to retrieve the binary key value, or
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a 41 byte buffer, to retrieve the key in a printable Z85 format.
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NOTE: to fetch a printable key, the buffer must be 41 bytes large
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to hold the 40-char key value and one null byte.
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[horizontal]
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Option value type:: binary data or Z85 text string
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Option value size:: 32 or 41
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Default value:: null
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Applicable socket types:: all, when using TCP transport
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ZMQ_CURVE_SERVERKEY: Retrieve current CURVE server key
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieves the current server key for the client socket. You can
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provide either a 32 byte buffer, to retrieve the binary key value, or
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a 41-byte buffer, to retrieve the key in a printable Z85 format.
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NOTE: to fetch a printable key, the buffer must be 41 bytes large
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to hold the 40-char key value and one null byte.
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[horizontal]
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Option value type:: binary data or Z85 text string
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Option value size:: 32 or 41
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Default value:: null
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Applicable socket types:: all, when using TCP transport
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ZMQ_EVENTS: Retrieve socket event state
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_EVENTS' option shall retrieve the event state for the specified
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'socket'. The returned value is a bit mask constructed by OR'ing a combination
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of the following event flags:
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*ZMQ_POLLIN*::
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Indicates that at least one message may be received from the specified socket
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without blocking.
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*ZMQ_POLLOUT*::
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Indicates that at least one message may be sent to the specified socket without
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blocking.
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The combination of a file descriptor returned by the 'ZMQ_FD' option being
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ready for reading but no actual events returned by a subsequent retrieval of
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the 'ZMQ_EVENTS' option is valid; applications should simply ignore this case
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and restart their polling operation/event loop.
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[horizontal]
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Option value type:: int
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Option value unit:: N/A (flags)
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Default value:: N/A
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Applicable socket types:: all
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ZMQ_FD: Retrieve file descriptor associated with the socket
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_FD' option shall retrieve the file descriptor associated with the
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specified 'socket'. The returned file descriptor can be used to integrate the
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socket into an existing event loop; the 0MQ library shall signal any pending
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events on the socket in an _edge-triggered_ fashion by making the file
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descriptor become ready for reading.
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NOTE: The ability to read from the returned file descriptor does not
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necessarily indicate that messages are available to be read from, or can be
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written to, the underlying socket; applications must retrieve the actual event
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state with a subsequent retrieval of the 'ZMQ_EVENTS' option.
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NOTE: The returned file descriptor is also used internally by the 'zmq_send'
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and 'zmq_recv' functions. As the descriptor is edge triggered, applications
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must update the state of 'ZMQ_EVENTS' after each invocation of 'zmq_send'
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or 'zmq_recv'.To be more explicit: after calling 'zmq_send' the socket may
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become readable (and vice versa) without triggering a read event on the
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file descriptor.
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CAUTION: The returned file descriptor is intended for use with a 'poll' or
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similar system call only. Applications must never attempt to read or write data
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to it directly, neither should they try to close it.
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[horizontal]
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Option value type:: int on POSIX systems, SOCKET on Windows
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Option value unit:: N/A
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Default value:: N/A
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Applicable socket types:: all
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ZMQ_GSSAPI_PLAINTEXT: Retrieve GSSAPI plaintext or encrypted status
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Returns the 'ZMQ_GSSAPI_PLAINTEXT' option, if any, previously set on the
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socket. A value of '1' means that communications will be plaintext. A value
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of '0' means communications will be encrypted.
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[horizontal]
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Option value type:: int
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Option value unit:: 0, 1
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Default value:: 0 (false)
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_GSSAPI_PRINCIPAL: Retrieve the name of the GSSAPI principal
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_GSSAPI_PRINCIPAL' option shall retrieve the principal name set for the
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GSSAPI security mechanism. The returned value shall be a NULL-terminated string
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and MAY be empty. The returned size SHALL include the terminating null byte.
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[horizontal]
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Option value type:: NULL-terminated character string
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Option value unit:: N/A
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Default value:: null string
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_GSSAPI_SERVER: Retrieve current GSSAPI server role
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Returns the 'ZMQ_GSSAPI_SERVER' option, if any, previously set on the socket.
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[horizontal]
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Option value type:: int
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Option value unit:: 0, 1
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Default value:: 0 (false)
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_GSSAPI_SERVICE_PRINCIPAL: Retrieve the name of the GSSAPI service principal
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_GSSAPI_SERVICE_PRINCIPAL' option shall retrieve the principal name of
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the GSSAPI server to which a GSSAPI client socket intends to connect. The
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returned value shall be a NULL-terminated string and MAY be empty. The returned
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size SHALL include the terminating null byte.
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[horizontal]
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Option value type:: NULL-terminated character string
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Option value unit:: N/A
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Default value:: null string
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_HANDSHAKE_IVL: Retrieve maximum handshake interval
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_HANDSHAKE_IVL' option shall retrieve the maximum handshake interval
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for the specified 'socket'. Handshaking is the exchange of socket configuration
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information (socket type, identity, security) that occurs when a connection
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is first opened, only for connection-oriented transports. If handshaking does
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not complete within the configured time, the connection shall be closed.
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The value 0 means no handshake time limit.
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[horizontal]
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Option value type:: int
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Option value unit:: milliseconds
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Default value:: 30000
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Applicable socket types:: all but ZMQ_STREAM, only for connection-oriented transports
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ZMQ_IDENTITY: Retrieve socket identity
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_IDENTITY' option shall retrieve the identity of the specified 'socket'.
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Socket identity is used only by request/reply pattern. Namely, it can be used
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in tandem with ROUTER socket to route messages to the peer with specific
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identity.
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Identity should be at least one byte and at most 255 bytes long. Identities
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starting with binary zero are reserved for use by 0MQ infrastructure.
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[horizontal]
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Option value type:: binary data
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Option value unit:: N/A
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Default value:: NULL
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Applicable socket types:: ZMQ_REP, ZMQ_REQ, ZMQ_ROUTER, ZMQ_DEALER.
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ZMQ_IMMEDIATE: Retrieve attach-on-connect value
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieve the state of the attach on connect value. If set to `1`, will delay the
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attachment of a pipe on connect until the underlying connection has completed.
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This will cause the socket to block if there are no other connections, but will
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prevent queues from filling on pipes awaiting connection.
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[horizontal]
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Option value type:: int
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Option value unit:: boolean
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Default value:: 0 (false)
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Applicable socket types:: all, primarily when using TCP/IPC transports.
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ZMQ_IPV4ONLY: Retrieve IPv4-only socket override status
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieve the IPv4-only option for the socket. This option is deprecated.
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Please use the ZMQ_IPV6 option.
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[horizontal]
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Option value type:: int
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Option value unit:: boolean
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Default value:: 1 (true)
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Applicable socket types:: all, when using TCP transports.
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ZMQ_IPV6: Retrieve IPv6 socket status
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieve the IPv6 option for the socket. A value of `1` means IPv6 is
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enabled on the socket, while `0` means the socket will use only IPv4.
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When IPv6 is enabled the socket will connect to, or accept connections
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from, both IPv4 and IPv6 hosts.
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[horizontal]
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Option value type:: int
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Option value unit:: boolean
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Default value:: 0 (false)
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Applicable socket types:: all, when using TCP transports.
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ZMQ_LAST_ENDPOINT: Retrieve the last endpoint set
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_LAST_ENDPOINT' option shall retrieve the last endpoint bound for
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TCP and IPC transports. The returned value will be a string in the form of
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a ZMQ DSN. Note that if the TCP host is INADDR_ANY, indicated by a *, then
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the returned address will be 0.0.0.0 (for IPv4).
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[horizontal]
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Option value type:: NULL-terminated character string
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Option value unit:: N/A
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Default value:: NULL
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Applicable socket types:: all, when binding TCP or IPC transports
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ZMQ_LINGER: Retrieve linger period for socket shutdown
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_LINGER' option shall retrieve the linger period for the specified
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'socket'. The linger period determines how long pending messages which have
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yet to be sent to a peer shall linger in memory after a socket is closed with
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linkzmq:zmq_close[3], and further affects the termination of the socket's
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context with linkzmq:zmq_term[3]. The following outlines the different
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behaviours:
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* The default value of '-1' specifies an infinite linger period. Pending
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messages shall not be discarded after a call to _zmq_close()_; attempting to
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terminate the socket's context with _zmq_term()_ shall block until all
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pending messages have been sent to a peer.
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* The value of '0' specifies no linger period. Pending messages shall be
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discarded immediately when the socket is closed with _zmq_close()_.
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* Positive values specify an upper bound for the linger period in milliseconds.
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Pending messages shall not be discarded after a call to _zmq_close()_;
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attempting to terminate the socket's context with _zmq_term()_ shall block
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until either all pending messages have been sent to a peer, or the linger
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period expires, after which any pending messages shall be discarded.
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[horizontal]
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Option value type:: int
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Option value unit:: milliseconds
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Default value:: -1 (infinite)
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Applicable socket types:: all
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ZMQ_MAXMSGSIZE: Maximum acceptable inbound message size
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The option shall retrieve limit for the inbound messages. If a peer sends
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a message larger than ZMQ_MAXMSGSIZE it is disconnected. Value of -1 means
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'no limit'.
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[horizontal]
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Option value type:: int64_t
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Option value unit:: bytes
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Default value:: -1
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Applicable socket types:: all
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ZMQ_MECHANISM: Retrieve current security mechanism
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_MECHANISM' option shall retrieve the current security mechanism
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for the socket.
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[horizontal]
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Option value type:: int
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Option value unit:: ZMQ_NULL, ZMQ_PLAIN, ZMQ_CURVE, or ZMQ_GSSAPI
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Default value:: ZMQ_NULL
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_MULTICAST_HOPS: Maximum network hops for multicast packets
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The option shall retrieve time-to-live used for outbound multicast packets.
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The default of 1 means that the multicast packets don't leave the local network.
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[horizontal]
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Option value type:: int
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Option value unit:: network hops
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Default value:: 1
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Applicable socket types:: all, when using multicast transports
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ZMQ_PLAIN_PASSWORD: Retrieve current password
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_PLAIN_PASSWORD' option shall retrieve the last password set for
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the PLAIN security mechanism. The returned value shall be a NULL-terminated
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string and MAY be empty. The returned size SHALL include the terminating
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null byte.
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[horizontal]
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Option value type:: NULL-terminated character string
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Option value unit:: N/A
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Default value:: null string
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_PLAIN_SERVER: Retrieve current PLAIN server role
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Returns the 'ZMQ_PLAIN_SERVER' option, if any, previously set on the socket.
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[horizontal]
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Option value type:: int
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Option value unit:: 0, 1
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Default value:: int
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_PLAIN_USERNAME: Retrieve current PLAIN username
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_PLAIN_USERNAME' option shall retrieve the last username set for
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the PLAIN security mechanism. The returned value shall be a NULL-terminated
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string and MAY be empty. The returned size SHALL include the terminating
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null byte.
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[horizontal]
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Option value type:: NULL-terminated character string
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Option value unit:: N/A
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Default value:: null string
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Applicable socket types:: all, when using TCP or IPC transports
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ZMQ_RATE: Retrieve multicast data rate
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_RATE' option shall retrieve the maximum send or receive data rate for
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multicast transports using the specified 'socket'.
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[horizontal]
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Option value type:: int
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Option value unit:: kilobits per second
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Default value:: 100
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Applicable socket types:: all, when using multicast transports
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ZMQ_RCVBUF: Retrieve kernel receive buffer size
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_RCVBUF' option shall retrieve the underlying kernel receive buffer
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size for the specified 'socket'. A value of zero means that the OS default is
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in effect. For details refer to your operating system documentation for the
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'SO_RCVBUF' socket option.
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[horizontal]
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Option value type:: int
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Option value unit:: bytes
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Default value:: 0
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Applicable socket types:: all
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ZMQ_RCVHWM: Retrieve high water mark for inbound messages
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_RCVHWM' option shall return the high water mark for inbound messages on
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the specified 'socket'. The high water mark is a hard limit on the maximum
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number of outstanding messages 0MQ shall queue in memory for any single peer
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that the specified 'socket' is communicating with. A value of zero means no
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limit.
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If this limit has been reached the socket shall enter an exceptional state and
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depending on the socket type, 0MQ shall take appropriate action such as
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blocking or dropping sent messages. Refer to the individual socket descriptions
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in linkzmq:zmq_socket[3] for details on the exact action taken for each socket
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type.
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[horizontal]
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Option value type:: int
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Option value unit:: messages
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Default value:: 1000
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Applicable socket types:: all
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ZMQ_RCVMORE: More message data parts to follow
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_RCVMORE' option shall return True (1) if the message part last
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received from the 'socket' was a data part with more parts to follow. If there
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are no data parts to follow, this option shall return False (0).
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Refer to linkzmq:zmq_send[3] and linkzmq:zmq_recv[3] for a detailed description
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of multi-part messages.
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[horizontal]
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Option value type:: int
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Option value unit:: boolean
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Default value:: N/A
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Applicable socket types:: all
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ZMQ_RCVTIMEO: Maximum time before a socket operation returns with EAGAIN
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Retrieve the timeout for recv operation on the socket. If the value is `0`,
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_zmq_recv(3)_ will return immediately, with a EAGAIN error if there is no
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message to receive. If the value is `-1`, it will block until a message is
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available. For all other values, it will wait for a message for that amount
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of time before returning with an EAGAIN error.
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[horizontal]
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Option value type:: int
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Option value unit:: milliseconds
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Default value:: -1 (infinite)
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Applicable socket types:: all
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ZMQ_RECONNECT_IVL: Retrieve reconnection interval
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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The 'ZMQ_RECONNECT_IVL' option shall retrieve the initial reconnection interval
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for the specified 'socket'. The reconnection interval is the period 0MQ shall
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wait between attempts to reconnect disconnected peers when using
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connection-oriented transports. The value -1 means no reconnection.
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NOTE: The reconnection interval may be randomized by 0MQ to prevent
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reconnection storms in topologies with a large number of peers per socket.
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|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: milliseconds
|
|
Default value:: 100
|
|
Applicable socket types:: all, only for connection-oriented transports
|
|
|
|
|
|
ZMQ_RECONNECT_IVL_MAX: Retrieve maximum reconnection interval
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
The 'ZMQ_RECONNECT_IVL_MAX' option shall retrieve 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.
|
|
|
|
NOTE: Values less than ZMQ_RECONNECT_IVL will be ignored.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: milliseconds
|
|
Default value:: 0 (only use ZMQ_RECONNECT_IVL)
|
|
Applicable socket types:: all, only for connection-oriented transport
|
|
|
|
|
|
ZMQ_RECOVERY_IVL: Get multicast recovery interval
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
The 'ZMQ_RECOVERY_IVL' option shall retrieve 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.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: milliseconds
|
|
Default value:: 10000
|
|
Applicable socket types:: all, when using multicast transports
|
|
|
|
|
|
ZMQ_SNDBUF: Retrieve kernel transmit buffer size
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
The 'ZMQ_SNDBUF' option shall retrieve the underlying kernel transmit buffer
|
|
size for the specified 'socket'. A value of zero means that the OS default is
|
|
in effect. For details refer to your operating system documentation for the
|
|
'SO_SNDBUF' socket option.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: bytes
|
|
Default value:: 0
|
|
Applicable socket types:: all
|
|
|
|
|
|
ZMQ_SNDHWM: Retrieves high water mark for outbound messages
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
The 'ZMQ_SNDHWM' option shall return 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.
|
|
|
|
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.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: messages
|
|
Default value:: 1000
|
|
Applicable socket types:: all
|
|
|
|
|
|
ZMQ_SNDTIMEO: Maximum time before a socket operation returns with EAGAIN
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
Retrieve 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.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: milliseconds
|
|
Default value:: -1 (infinite)
|
|
Applicable socket types:: all
|
|
|
|
|
|
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.
|
|
|
|
[horizontal]
|
|
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.
|
|
|
|
|
|
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.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: -1,>0
|
|
Default value:: -1 (leave to OS default)
|
|
Applicable socket types:: all, when using TCP transports.
|
|
|
|
|
|
ZMQ_TCP_KEEPALIVE_IDLE: Override TCP_KEEPCNT(or TCP_KEEPALIVE on some OS)
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
Override 'TCP_KEEPCNT'(or 'TCP_KEEPALIVE' on some OS) socket option (where
|
|
supported by OS). The default value of `-1` means to skip any overrides and
|
|
leave it to OS default.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: -1,>0
|
|
Default value:: -1 (leave to OS default)
|
|
Applicable socket types:: all, when using TCP transports.
|
|
|
|
|
|
ZMQ_TCP_KEEPALIVE_INTVL: Override TCP_KEEPINTVL socket option
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
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.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: -1,>0
|
|
Default value:: -1 (leave to OS default)
|
|
Applicable socket types:: all, when using TCP transports.
|
|
|
|
|
|
ZMQ_TOS: Retrieve the Type-of-Service socket override status
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
Retrieve the IP_TOS option for the socket.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: >0
|
|
Default value:: 0
|
|
Applicable socket types:: all, only for connection-oriented transports
|
|
|
|
|
|
ZMQ_TYPE: Retrieve socket type
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
The 'ZMQ_TYPE' option shall retrieve the socket type for the specified
|
|
'socket'. The socket type is specified at socket creation time and
|
|
cannot be modified afterwards.
|
|
|
|
[horizontal]
|
|
Option value type:: int
|
|
Option value unit:: N/A
|
|
Default value:: N/A
|
|
Applicable socket types:: all
|
|
|
|
|
|
ZMQ_ZAP_DOMAIN: Retrieve RFC 27 authentication domain
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
The 'ZMQ_ZAP_DOMAIN' option shall retrieve the last ZAP domain set for
|
|
the socket. The returned value shall be a NULL-terminated string and MAY
|
|
be empty. The returned size SHALL include the terminating null byte.
|
|
|
|
[horizontal]
|
|
Option value type:: character string
|
|
Option value unit:: N/A
|
|
Default value:: not set
|
|
Applicable socket types:: all, when using TCP transport
|
|
|
|
ZMQ_IDENTITY_FD: Retrieve FD associated with igven identity
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
The 'ZMQ_IDENTITY_FD' option shall retrieve the FD associated with given identity.
|
|
call _zmq_getsockopt()_ with _option_value_ / _option_len_ pointing to memory
|
|
holding the identity string. On return the start of _option_value_ buffer will be
|
|
filled with file descriptor of the pipe with given identity if found. If the identity
|
|
is not found ENOTSOCK is returned as _zmq_getsockopt()_ result. When the pipe is not
|
|
using FD as lower transport you might get -1 as FD. NB: _option_value_ must be always
|
|
big enough to hold sizeof(fd_t) bytes no matter how small the identity length is.
|
|
|
|
[horizontal]
|
|
Option value type:: character string/fd_t
|
|
Option value unit:: N/A
|
|
Default value:: not set
|
|
Applicable socket types:: ROUTER
|
|
|
|
|
|
RETURN VALUE
|
|
------------
|
|
The _zmq_getsockopt()_ function shall return zero if successful. Otherwise it
|
|
shall return `-1` and set 'errno' to one of the values defined below.
|
|
|
|
|
|
ERRORS
|
|
------
|
|
*EINVAL*::
|
|
The requested option _option_name_ is unknown, or the requested _option_len_ or
|
|
_option_value_ is invalid, or the size of the buffer pointed to by
|
|
_option_value_, as specified by _option_len_, is insufficient for storing the
|
|
option value.
|
|
*ETERM*::
|
|
The 0MQ 'context' associated with the specified 'socket' was terminated.
|
|
*ENOTSOCK*::
|
|
The provided 'socket' was invalid.
|
|
*EINTR*::
|
|
The operation was interrupted by delivery of a signal.
|
|
|
|
|
|
EXAMPLE
|
|
-------
|
|
.Retrieving the high water mark for outgoing messages
|
|
----
|
|
/* Retrieve high water mark into sndhwm */
|
|
int sndhwm;
|
|
size_t sndhwm_size = sizeof (sndhwm);
|
|
rc = zmq_getsockopt (socket, ZMQ_SNDHWM, &sndhwm, &sndhwm_size);
|
|
assert (rc == 0);
|
|
----
|
|
|
|
|
|
SEE ALSO
|
|
--------
|
|
linkzmq:zmq_setsockopt[3]
|
|
linkzmq:zmq_socket[3]
|
|
linkzmq:zmq[7]
|
|
|
|
|
|
AUTHORS
|
|
-------
|
|
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>.
|