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Diffstat (limited to 'doc/zmq_sendmsg.txt')
| -rw-r--r-- | doc/zmq_sendmsg.txt | 38 |
1 files changed, 18 insertions, 20 deletions
diff --git a/doc/zmq_sendmsg.txt b/doc/zmq_sendmsg.txt index 7995304..244c0bd 100644 --- a/doc/zmq_sendmsg.txt +++ b/doc/zmq_sendmsg.txt @@ -4,7 +4,7 @@ zmq_sendmsg(3) NAME ---- -zmq_sendmsg - send a message on a socket +zmq_sendmsg - send a message part on a socket SYNOPSIS @@ -23,15 +23,16 @@ Specifies that the operation should be performed in non-blocking mode. If the message cannot be queued on the 'socket', the _zmq_sendmsg()_ function shall fail with 'errno' set to EAGAIN. +*ZMQ_SNDLABEL*:: +Specifies that the message part being sent is an address 'label', and that +further message parts are to follow. Refer to linkzmq:zmq_socket[3] for the +semantics of address labels in each socket pattern. + *ZMQ_SNDMORE*:: Specifies that the message being sent is a multi-part message, and that further message parts are to follow. Refer to the section regarding multi-part messages below for a detailed description. -*ZMQ_SNDLABEL*:: -Specifies that the message being sent is a label. Labels are used internally -by 0MQ. - The _zmq_msg_t_ structure passed to _zmq_sendmsg()_ is nullified during the call. If you want to send the same message to multiple sockets you have to copy it using (e.g. using _zmq_msg_copy()_). @@ -43,20 +44,16 @@ the 'socket' and 0MQ has assumed responsibility for the message. Multi-part messages ~~~~~~~~~~~~~~~~~~~ -A 0MQ message is composed of 1 or more message parts; each message part is an -independent 'zmq_msg_t' in its own right. 0MQ ensures atomic delivery of -messages; peers shall receive either all _message parts_ of a message or none -at all. - -The total number of message parts is unlimited. - -An application wishing to send a multi-part message does so by specifying the -'ZMQ_SNDMORE' flag to _zmq_sendmsg()_. The presence of this flag indicates to -0MQ that the message being sent is a multi-part message and that more message -parts are to follow. When the application wishes to send the final message part -it does so by calling _zmq_sendmsg()_ without the 'ZMQ_SNDMORE' flag; this -indicates that no more message parts are to follow. +A 0MQ message is composed of 1 or more message parts, starting with zero or +more address 'label' parts, followed by 1 or more 'data' parts. Each message +part is an independent 'zmq_msg_t' in its own right. 0MQ ensures atomic +delivery of messages; peers shall receive either all _message parts_ of a +message or none at all. The total number of message parts is unlimited except +by available memory. +An application that sends multipart messages must use the _ZMQ_SNDMORE_ flag +when sending each data part except the final one. An application that sends +address labels must use _ZMQ_SNDLABEL_ when sending each label. RETURN VALUE ------------ @@ -126,5 +123,6 @@ linkzmq:zmq[7] AUTHORS ------- -The 0MQ documentation was written by Martin Sustrik <sustrik@250bpm.com> and -Martin Lucina <mato@kotelna.sk>. ++This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin ++Lucina <mato@kotelna.sk> and Pieter Hintjens <ph@imatix.com>. + |