diff options
| -rw-r--r-- | doc/Makefile.am | 3 | ||||
| -rw-r--r-- | doc/zmq_recv.txt | 70 | ||||
| -rw-r--r-- | doc/zmq_recvmsg.txt | 124 | ||||
| -rw-r--r-- | doc/zmq_send.txt | 70 | ||||
| -rw-r--r-- | doc/zmq_sendmsg.txt | 127 |
5 files changed, 304 insertions, 90 deletions
diff --git a/doc/Makefile.am b/doc/Makefile.am index eec7209..dae71be 100644 --- a/doc/Makefile.am +++ b/doc/Makefile.am @@ -2,7 +2,8 @@ MAN3 = zmq_bind.3 zmq_close.3 zmq_connect.3 zmq_init.3 \ zmq_msg_close.3 zmq_msg_copy.3 zmq_msg_data.3 zmq_msg_init.3 \ zmq_msg_init_data.3 zmq_msg_init_size.3 zmq_msg_move.3 zmq_msg_size.3 \ zmq_poll.3 zmq_recv.3 zmq_send.3 zmq_setsockopt.3 zmq_socket.3 \ - zmq_strerror.3 zmq_term.3 zmq_version.3 zmq_getsockopt.3 zmq_errno.3 + zmq_strerror.3 zmq_term.3 zmq_version.3 zmq_getsockopt.3 zmq_errno.3 \ + zmq_sendmsg.3 zmq_recvmsg.3 MAN7 = zmq.7 zmq_tcp.7 zmq_pgm.7 zmq_epgm.7 zmq_inproc.7 zmq_ipc.7 MAN_DOC = $(MAN1) $(MAN3) $(MAN7) diff --git a/doc/zmq_recv.txt b/doc/zmq_recv.txt index 0b6e0e4..f09d298 100644 --- a/doc/zmq_recv.txt +++ b/doc/zmq_recv.txt @@ -9,30 +9,29 @@ zmq_recv - receive a message from a socket SYNOPSIS -------- -*int zmq_recv (void '*socket', zmq_msg_t '*msg', int 'flags');* +*int zmq_recv (void '*socket', void '*buf', size_t 'len', int 'flags');* DESCRIPTION ----------- -The _zmq_recv()_ function shall receive a message from the socket referenced by -the 'socket' argument and store it in the message referenced by the 'msg' -argument. Any content previously stored in 'msg' shall be properly deallocated. -If there are no messages available on the specified 'socket' the _zmq_recv()_ -function shall block until the request can be satisfied. The 'flags' argument -is a combination of the flags defined below: +The _zmq_recv()_ function shall receive a message from the socket referenced +by the 'socket' argument and store it in the buffer referenced by the 'buf' +argument. Any bytes exceeding the length specified by the 'len' argument shall +be truncated. If there are no messages available on the specified 'socket' +the _zmq_recv()_ function shall block until the request can be satisfied. +The 'flags' argument is a combination of the flags defined below: *ZMQ_DONTWAIT*:: Specifies that the operation should be performed in non-blocking mode. If there -are no messages available on the specified 'socket', the _zmq_recv()_ function -shall fail with 'errno' set to EAGAIN. +are no messages available on the specified 'socket', the _zmq_recv()_ +function shall fail with 'errno' set to EAGAIN. 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. +A 0MQ message is composed of 1 or more message parts. 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. @@ -46,8 +45,10 @@ shall report a value of zero. Otherwise, _ZMQ_RCVMORE_ shall report a value of RETURN VALUE ------------ -The _zmq_recv()_ function shall return zero if successful. Otherwise it shall -return `-1` and set 'errno' to one of the values defined below. +The _zmq_recv()_ function shall return number of bytes in the message +if successful. Note that the value can exceed the value of the 'len' parameter +in case the message was truncated. If not successful the function shall return +`-1` and set 'errno' to one of the values defined below. ERRORS @@ -57,8 +58,8 @@ Non-blocking mode was requested and no messages are available at the moment. *ENOTSUP*:: The _zmq_recv()_ operation is not supported by this socket type. *EFSM*:: -The _zmq_recv()_ operation cannot be performed on this socket at the moment due -to the socket not being in the appropriate state. This error may occur with +The _zmq_recv()_ operation cannot be performed on this socket at the moment +due to the socket not being in the appropriate state. This error may occur with socket types that switch between several states, such as ZMQ_REP. See the _messaging patterns_ section of linkzmq:zmq_socket[3] for more information. *ETERM*:: @@ -68,48 +69,23 @@ The provided 'socket' was invalid. *EINTR*:: The operation was interrupted by delivery of a signal before a message was available. -*EFAULT*:: -The message passed to the function was invalid. EXAMPLE ------- .Receiving a message from a socket ---- -/* Create an empty 0MQ message */ -zmq_msg_t msg; -int rc = zmq_msg_init (&msg); -assert (rc == 0); -/* Block until a message is available to be received from socket */ -rc = zmq_recv (socket, &msg, 0); -assert (rc == 0); -/* Release message */ -zmq_msg_close (&msg); ----- - -.Receiving a multi-part message ----- -int64_t more; -size_t more_size = sizeof more; -do { - /* Create an empty 0MQ message to hold the message part */ - zmq_msg_t part; - int rc = zmq_msg_init (&part); - assert (rc == 0); - /* Block until a message is available to be received from socket */ - rc = zmq_recv (socket, &part, 0); - assert (rc == 0); - /* Determine if more message parts are to follow */ - rc = zmq_getsockopt (socket, ZMQ_RCVMORE, &more, &more_size); - assert (rc == 0); - zmq_msg_close (&part); -} while (more); +char buf [256]; +nbytes = zmq_recv (socket, buf, 256, 0); +assert (nbytes != -1); ---- SEE ALSO -------- +linkzmq:zmq_recvmsg[3] linkzmq:zmq_send[3] +linkzmq:zmq_sendmsg[3] linkzmq:zmq_getsockopt[3] linkzmq:zmq_socket[7] linkzmq:zmq[7] diff --git a/doc/zmq_recvmsg.txt b/doc/zmq_recvmsg.txt new file mode 100644 index 0000000..640768a --- /dev/null +++ b/doc/zmq_recvmsg.txt @@ -0,0 +1,124 @@ +zmq_recvmsg(3) +============== + + +NAME +---- +zmq_recvmsg - receive a message from a socket + + +SYNOPSIS +-------- +*int zmq_recvmsg (void '*socket', zmq_msg_t '*msg', int 'flags');* + + +DESCRIPTION +----------- +The _zmq_recvmsg()_ function shall receive a message from the socket referenced +by the 'socket' argument and store it in the message referenced by the 'msg' +argument. Any content previously stored in 'msg' shall be properly deallocated. +If there are no messages available on the specified 'socket' the _zmq_recvmsg()_ +function shall block until the request can be satisfied. The 'flags' argument +is a combination of the flags defined below: + +*ZMQ_DONTWAIT*:: +Specifies that the operation should be performed in non-blocking mode. If there +are no messages available on the specified 'socket', the _zmq_recvmsg()_ +function shall fail with 'errno' set to EAGAIN. + + +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 determine if a message is composed of multiple parts +does so by retrieving the value of the _ZMQ_RCVMORE_ socket option on the +'socket' it is receiving the message from. If there are no message parts to +follow, or if the message is not composed of multiple parts, _ZMQ_RCVMORE_ +shall report a value of zero. Otherwise, _ZMQ_RCVMORE_ shall report a value of +1, indicating that more message parts are to follow. + + +RETURN VALUE +------------ +The _zmq_recvmsg()_ function shall return number of bytes in the message +if successful. Otherwise it shall return `-1` and set 'errno' to one of the +values defined below. + + +ERRORS +------ +*EAGAIN*:: +Non-blocking mode was requested and no messages are available at the moment. +*ENOTSUP*:: +The _zmq_recvmsg()_ operation is not supported by this socket type. +*EFSM*:: +The _zmq_recvmsg()_ operation cannot be performed on this socket at the moment +due to the socket not being in the appropriate state. This error may occur with +socket types that switch between several states, such as ZMQ_REP. See the +_messaging patterns_ section of linkzmq:zmq_socket[3] for more information. +*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 before a message was +available. +*EFAULT*:: +The message passed to the function was invalid. + + +EXAMPLE +------- +.Receiving a message from a socket +---- +/* Create an empty 0MQ message */ +zmq_msg_t msg; +int rc = zmq_msg_init (&msg); +assert (rc == 0); +/* Block until a message is available to be received from socket */ +rc = zmq_recvmsg (socket, &msg, 0); +assert (rc != -1); +/* Release message */ +zmq_msg_close (&msg); +---- + +.Receiving a multi-part message +---- +int64_t more; +size_t more_size = sizeof more; +do { + /* Create an empty 0MQ message to hold the message part */ + zmq_msg_t part; + int rc = zmq_msg_init (&part); + assert (rc == 0); + /* Block until a message is available to be received from socket */ + rc = zmq_recvmsg (socket, &part, 0); + assert (rc != -1); + /* Determine if more message parts are to follow */ + rc = zmq_getsockopt (socket, ZMQ_RCVMORE, &more, &more_size); + assert (rc == 0); + zmq_msg_close (&part); +} while (more); +---- + + +SEE ALSO +-------- +linkzmq:zmq_recv[3] +linkzmq:zmq_send[3] +linkzmq:zmq_sendmsg[3] +linkzmq:zmq_getsockopt[3] +linkzmq:zmq_socket[7] +linkzmq:zmq[7] + + +AUTHORS +------- +The 0MQ documentation was written by Martin Sustrik <sustrik@250bpm.com> and +Martin Lucina <mato@kotelna.sk>. diff --git a/doc/zmq_send.txt b/doc/zmq_send.txt index 52a50ae..2b51953 100644 --- a/doc/zmq_send.txt +++ b/doc/zmq_send.txt @@ -9,19 +9,19 @@ zmq_send - send a message on a socket SYNOPSIS -------- -*int zmq_send (void '*socket', zmq_msg_t '*msg', int 'flags');* +*int zmq_send (void '*socket', void '*buf', size_t 'len', int 'flags');* DESCRIPTION ----------- -The _zmq_send()_ function shall queue the message referenced by the 'msg' -argument to be sent to the socket referenced by the 'socket' argument. The -'flags' argument is a combination of the flags defined below: +The _zmq_send()_ function shall queue a message created from the buffer +referenced by the 'buf' and 'len' arguments. The 'flags' argument is +a combination of the flags defined below: *ZMQ_DONTWAIT*:: Specifies that the operation should be performed in non-blocking mode. If the -message cannot be queued on the 'socket', the _zmq_send()_ function shall fail -with 'errno' set to EAGAIN. +message cannot be queued on the 'socket', the _zmq_send()_ function shall +fail with 'errno' set to EAGAIN. *ZMQ_SNDMORE*:: Specifies that the message being sent is a multi-part message, and that further @@ -32,10 +32,6 @@ below for a detailed description. Specifies that the message being sent is a label. Labels are used internally by 0MQ. -The _zmq_msg_t_ structure passed to _zmq_send()_ 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()_). - NOTE: A successful invocation of _zmq_send()_ does not indicate that the message has been transmitted to the network, only that it has been queued on the 'socket' and 0MQ has assumed responsibility for the message. @@ -43,25 +39,26 @@ 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. +A 0MQ message is composed of 1 or more message parts; each invocation of +_zmq_send()_ creates an independent message part 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_send()_. 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_send()_ without the 'ZMQ_SNDMORE' flag; this indicates -that no more message parts are to follow. +'ZMQ_SNDMORE' flag to _zmq_send()_. 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_send()_ without the 'ZMQ_SNDMORE' flag; this +indicates that no more message parts are to follow. RETURN VALUE ------------ -The _zmq_send()_ function shall return zero if successful. Otherwise it shall -return `-1` and set 'errno' to one of the values defined below. +The _zmq_send()_ function shall return number of bytes in the message +if successful. Otherwise it shall return `-1` and set 'errno' to one of the +values defined below. ERRORS @@ -71,8 +68,8 @@ Non-blocking mode was requested and the message cannot be sent at the moment. *ENOTSUP*:: The _zmq_send()_ operation is not supported by this socket type. *EFSM*:: -The _zmq_send()_ operation cannot be performed on this socket at the moment due -to the socket not being in the appropriate state. This error may occur with +The _zmq_send()_ operation cannot be performed on this socket at the moment +due to the socket not being in the appropriate state. This error may occur with socket types that switch between several states, such as ZMQ_REP. See the _messaging patterns_ section of linkzmq:zmq_socket[3] for more information. *ETERM*:: @@ -82,38 +79,27 @@ The provided 'socket' was invalid. *EINTR*:: The operation was interrupted by delivery of a signal before the message was sent. -*EFAULT*:: -Invalid message. EXAMPLE ------- -.Filling in a message and sending it to a socket ----- -/* Create a new message, allocating 6 bytes for message content */ -zmq_msg_t msg; -int rc = zmq_msg_init_size (&msg, 6); -assert (rc == 0); -/* Fill in message content with 'AAAAAA' */ -memset (zmq_msg_data (&msg), 'A', 6); -/* Send the message to the socket */ -rc = zmq_send (socket, &msg, 0); -assert (rc == 0); ----- - .Sending a multi-part message ---- /* Send a multi-part message consisting of three parts to socket */ -rc = zmq_send (socket, &part1, ZMQ_SNDMORE); -rc = zmq_send (socket, &part2, ZMQ_SNDMORE); +rc = zmq_send (socket, "ABC", 3, ZMQ_SNDMORE); +assert (rc == 3); +rc = zmq_send (socket, "DEFGH", 5, ZMQ_SNDMORE); +assert (rc == 5); /* Final part; no more parts to follow */ -rc = zmq_send (socket, &part3, 0); +rc = zmq_send (socket, "JK", 2, 0); +assert (rc == 2); ---- - SEE ALSO -------- +linkzmq:zmq_sendmsg[3] linkzmq:zmq_recv[3] +linkzmq:zmq_recvmsg[3] linkzmq:zmq_socket[7] linkzmq:zmq[7] diff --git a/doc/zmq_sendmsg.txt b/doc/zmq_sendmsg.txt new file mode 100644 index 0000000..ddf585c --- /dev/null +++ b/doc/zmq_sendmsg.txt @@ -0,0 +1,127 @@ +zmq_sendmsg(3) +============== + + +NAME +---- +zmq_sendmsg - send a message on a socket + + +SYNOPSIS +-------- +*int zmq_sendmsg (void '*socket', zmq_msg_t '*msg', int 'flags');* + + +DESCRIPTION +----------- +The _zmq_send()_ function shall queue the message referenced by the 'msg' +argument to be sent to the socket referenced by the 'socket' argument. The +'flags' argument is a combination of the flags defined below: + +*ZMQ_DONTWAIT*:: +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_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()_). + +NOTE: A successful invocation of _zmq_sendmsg()_ does not indicate that the +message has been transmitted to the network, only that it has been queued on +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. + + +RETURN VALUE +------------ +The _zmq_sendmsg()_ function shall return number of bytes in the message +if successful. Otherwise it shall return `-1` and set 'errno' to one of the +values defined below. + + +ERRORS +------ +*EAGAIN*:: +Non-blocking mode was requested and the message cannot be sent at the moment. +*ENOTSUP*:: +The _zmq_sendmsg()_ operation is not supported by this socket type. +*EFSM*:: +The _zmq_sendmsg()_ operation cannot be performed on this socket at the moment +due to the socket not being in the appropriate state. This error may occur with +socket types that switch between several states, such as ZMQ_REP. See the +_messaging patterns_ section of linkzmq:zmq_socket[3] for more information. +*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 before the message was +sent. +*EFAULT*:: +Invalid message. + + +EXAMPLE +------- +.Filling in a message and sending it to a socket +---- +/* Create a new message, allocating 6 bytes for message content */ +zmq_msg_t msg; +int rc = zmq_msg_init_size (&msg, 6); +assert (rc == 0); +/* Fill in message content with 'AAAAAA' */ +memset (zmq_msg_data (&msg), 'A', 6); +/* Send the message to the socket */ +rc = zmq_sendmsg (socket, &msg, 0); +assert (rc == 6); +---- + +.Sending a multi-part message +---- +/* Send a multi-part message consisting of three parts to socket */ +rc = zmq_sendmsg (socket, &part1, ZMQ_SNDMORE); +rc = zmq_sendmsg (socket, &part2, ZMQ_SNDMORE); +/* Final part; no more parts to follow */ +rc = zmq_sendmsg (socket, &part3, 0); +---- + + +SEE ALSO +-------- +linkzmq:zmq_recv[3] +linkzmq:zmq_recv[3] +linkzmq:zmq_recvmsg[3] +linkzmq:zmq_socket[7] +linkzmq:zmq[7] + + +AUTHORS +------- +The 0MQ documentation was written by Martin Sustrik <sustrik@250bpm.com> and +Martin Lucina <mato@kotelna.sk>. |