From 4a7aad06d95701cf232198093ce396dcdbb53e5b Mon Sep 17 00:00:00 2001 From: Martin Sustrik Date: Thu, 16 Feb 2012 10:01:47 +0900 Subject: ZeroMQ renamed to Crossroads Signed-off-by: Martin Sustrik --- doc/xs_recv.txt | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) create mode 100644 doc/xs_recv.txt (limited to 'doc/xs_recv.txt') diff --git a/doc/xs_recv.txt b/doc/xs_recv.txt new file mode 100644 index 0000000..26a6c54 --- /dev/null +++ b/doc/xs_recv.txt @@ -0,0 +1,94 @@ +xs_recv(3) +========== + + +NAME +---- +xs_recv - receive a message part from a socket + + +SYNOPSIS +-------- +*int xs_recv (void '*socket', void '*buf', size_t 'len', int 'flags');* + + +DESCRIPTION +----------- +The _xs_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 _xs_recv()_ function shall block until the request can be satisfied. +The 'flags' argument is a combination of the flags defined below: + +*XS_DONTWAIT*:: +Specifies that the operation should be performed in non-blocking mode. If there +are no messages available on the specified 'socket', the _xs_recv()_ +function shall fail with 'errno' set to EAGAIN. + + +Multi-part messages +~~~~~~~~~~~~~~~~~~~ +A Crossroads message is composed of 1 or more message parts. Each message +part is an independent 'xs_msg_t' in its own right. Crossroads ensure 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 processes multipart messages must use the _XS_RCVMORE_ +linkxs:xs_getsockopt[3] option after calling _xs_recv()_ to determine if +there are further parts to receive. + +RETURN VALUE +------------ +The _xs_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 +------ +*EAGAIN*:: +Non-blocking mode was requested and no messages are available at the moment. +*ENOTSUP*:: +The _xs_recv()_ operation is not supported by this socket type. +*EFSM*:: +The _xs_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 XS_REP. See the +_messaging patterns_ section of linkxs:xs_socket[3] for more information. +*ETERM*:: +The '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. + + +EXAMPLE +------- +.Receiving a message from a socket +---- +char buf [256]; +nbytes = xs_recv (socket, buf, 256, 0); +assert (nbytes != -1); +---- + + +SEE ALSO +-------- +linkxs:xs_recvmsg[3] +linkxs:xs_send[3] +linkxs:xs_sendmsg[3] +linkxs:xs_getsockopt[3] +linkxs:xs_socket[7] +linkxs:xs[7] + + +AUTHORS +------- ++This man page was written by Martin Sustrik , Martin ++Lucina and Pieter Hintjens . + -- cgit v1.2.3