Hi,
is it possible to detect, whether the other side has closed a socket
connection when writing on this socket?
When i am trying this with two R instances R 1 and R 2, i expected
that the last writeLines would give an error, but the call seems to be
successfull:
R 1> s<-socketConnection(port=2000, server=T, blocking=T,
open="r+b")
R 2> s<-socketConnection(port=2000, server=F, blocking=T,
open="r+b")
R 1> CloseAllConnections()
R 2> writeLines("test", s) # seems to succeed
R 2> isIncomplete(s) # returns FALSE
Only if i write a very long strings instead of "test", the writeLines
call blocks and gives a warning after timing out. The same happens with
writeBin.
I tried this with R-2.1.0 and R-2.0.1 under Ubuntu hoary.
This is a problem for me, because i am writing a statistics server
in R, which communicates over a socket connection with a Java web
server. The other side has timeouts and may close the connection
before the result of a long-standing calculation has been sent.
In this case, the R server should detect, that the connection
was closed and try to reconnect. But this is not possible, if the
write seems successfull.
Is this a bug, which will be solved in future releases, or a feature?
Christian