| send_aio | R Documentation |
Send data asynchronously over a connection (Socket, Context or Stream).
send_aio(con, data, mode = c("serial", "raw", "next"), timeout = NULL)
con |
a Socket, Context or Stream. |
data |
an object (a vector, if mode = 'raw'). |
mode |
[default 'serial'] one of 'serial' to send serialised R objects, 'raw' to send atomic vectors of any type as a raw byte vector, or 'next' (see 'Send Modes' section below). Alternatively, specify an integer position in the vector of choices e.g. 1L for 'serial' or 2L for 'raw' etc. For Streams, 'raw' is the only option and this argument is ignored. |
timeout |
[default NULL] integer value in milliseconds or NULL, which applies a socket-specific default, usually the same as no timeout. |
Async send is always non-blocking and returns a 'sendAio' immediately.
For a 'sendAio', the send result is available at $result. An
'unresolved' logical NA is returned if the async operation is yet to
complete. The resolved value will be zero on success, or else an integer
error code.
To wait for and check the result of the send operation, use
call_aio on the returned 'sendAio' object.
Alternatively, to stop the async operation, use stop_aio.
A 'sendAio' (object of class 'sendAio') (invisibly).
The default mode 'serial' sends serialised R objects to ensure perfect reproducibility within R. When receiving, the corresponding mode 'serial' should be used.
Mode 'raw' sends atomic vectors of any type as a raw byte vector, and must be used when interfacing with external applications or raw system sockets, where R serialization is not in use. When receiving, the mode corresponding to the vector sent should be used.
Mode 'next' sends serialised R objects, with native extensions enabled by
next_config. This configures custom serialization and
unserialization functions for external pointer reference objects. When
receiving, mode 'serial' should be used as 'next' sends are fully
compatible.
pub <- socket("pub", dial = "inproc://nanonext")
res <- send_aio(pub, data.frame(a = 1, b = 2), timeout = 100)
res
res$result
res <- send_aio(pub, "example message", mode = "raw", timeout = 100)
call_aio(res)$result
close(pub)