Open a new Context to be used with a Socket. The purpose of a Context is to permit applications to share a single socket, with its underlying dialers and listeners, while still benefiting from separate state tracking.
Details
Contexts allow the independent and concurrent use of stateful operations using the same socket. For example, two different contexts created on a rep socket can each receive requests, and send replies to them, without any regard to or interference with each other.
Only the following protocols support creation of contexts: req, rep, sub (in a pub/sub pattern), surveyor, respondent.
To send and receive over a context use send and
recv or their async counterparts send_aio and
recv_aio.
For nano objects, use the $context_open() method, which will attach a
new context at $context. See nano.
Examples
s <- socket("req", listen = "inproc://nanonext")
ctx <- context(s)
ctx
#> < nanoContext >
#> - id: 1
#> - socket: 5
#> - state: opened
#> - protocol: req
close(ctx)
close(s)
n <- nano("req", listen = "inproc://nanonext")
n$context_open()
n$context
#> < nanoContext >
#> - id: 2
#> - socket: 6
#> - state: opened
#> - protocol: req
n$context_open()
n$context
#> < nanoContext >
#> - id: 3
#> - socket: 6
#> - state: opened
#> - protocol: req
n$context_close()
#> [1] 0
n$close()