Send Receive Functions
From pbdZMQ v0.2-4
by Wei-Chen Chen
Send Receive Functions
Send and receive functions
- Keywords
- programming
Usage
zmq.send(socket, buf, flags = .pbd_env$ZMQ.SR$BLOCK)
zmq.recv(socket, len = 1024L, flags = .pbd_env$ZMQ.SR$BLOCK, buf.type = c("char", "raw"))
Arguments
- socket
- a ZMQ socket
- buf
- a buffer to be sent
- flags
- a flag for the method using by
zmq_send
andzmq_recv
- len
- a length of buffer to be received, default 1024 bytes
- buf.type
- buffer type to be received
Details
zmq.send()
is a high level R function calling ZMQ C API
zmq_send()
sending buf
out.
zmq.recv()
is a high level R function calling ZMQ C API
zmq_recv()
receiving buffers of length len
according to the
buf.type
.
flags
see ZMQ.SR()
for detail options of send and
receive functions.
buf.type
currently supports char
and raw
which are both
in R object format.
Value
zmq.send()
returns number of bytes (invisible) in the sent
message if successful, otherwise returns -1 (invisible) and sets
errno
to the error value, see ZeroMQ manual for details.zmq.recv()
returns a list (ret
) containing the received buffer
ret$buf
and the length of received buffer (ret$len
which is
less or equal to the input len
) if successful, otherwise returns -1
and sets errno
to the error value, see ZeroMQ manual for details.
References
ZeroMQ/4.1.0 API Reference: http://api.zeromq.org/4-1:_start
Programming with Big Data in R Website: http://r-pbd.org/
See Also
zmq.msg.send()
, zmq.msg.recv()
.
Examples
## Not run:
# ### Using request-reply pattern.
#
# ### At the server, run next in background or the other window.
# library(pbdZMQ, quietly = TRUE)
#
# context <- zmq.ctx.new()
# responder <- zmq.socket(context, .pbd_env$ZMQ.ST$REP)
# zmq.bind(responder, "tcp://*:5555")
# for(i.res in 1:5){
# buf <- zmq.recv(responder, 10L)
# cat(buf$buf, "\n")
# Sys.sleep(0.5)
# zmq.send(responder, "World")
# }
# zmq.close(responder)
# zmq.ctx.destroy(context)
#
#
# ### At a client, run next in foreground.
# library(pbdZMQ, quietly = TRUE)
#
# context <- zmq.ctx.new()
# requester <- zmq.socket(context, .pbd_env$ZMQ.ST$REQ)
# zmq.connect(requester, "tcp://localhost:5555")
# for(i.req in 1:5){
# cat("Sending Hello ", i.req, "\n")
# zmq.send(requester, "Hello")
# buf <- zmq.recv(requester, 10L)
# cat("Received World ", i.req, "\n")
# }
# zmq.close(requester)
# zmq.ctx.destroy(context)
# ## End(Not run)
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