R help - Aug 2017 - Problem with serialization via readRDS() on a textConnection()

(Sorry for not linking to your message; I accidentally deleted the 
original copy of your message.)

Your code

 > zz = textConnection('tempConnection', 'wb')
 > saveRDS(c("a", "b", "c"), zz, ascii = TRUE)
 > serialized_obj = paste(textConnectionValue(zz), collapse='\n')
 > readRDS(textConnection(serialized_obj))
Error in gzcon(file) : 'read' not enabled for this connection

has one problem:  textConnectionValue(zz) may not be the complete text 
because zz hasn't been closed.  You should close(zz), then get the 
result from the variable tempConnection.

However, this doesn't fix the problem you saw, which appears to be a bug 
in readRDS or gzcon.  I'll post it to the bug list.

Duncan Murdoch

On 09/08/2017 9:01 AM, Duncan Murdoch wrote:
> (Sorry for not linking to your message; I accidentally deleted the
> original copy of your message.)
>
> Your code
>
>  > zz = textConnection('tempConnection', 'wb')
>  > saveRDS(c("a", "b", "c"), zz, ascii =
TRUE)
>  > serialized_obj = paste(textConnectionValue(zz),
collapse='\n')
>  > readRDS(textConnection(serialized_obj))
> Error in gzcon(file) : 'read' not enabled for this connection
>
> has one problem:  textConnectionValue(zz) may not be the complete text
> because zz hasn't been closed.  You should close(zz), then get the
> result from the variable tempConnection.
>
> However, this doesn't fix the problem you saw, which appears to be a
bug
> in readRDS or gzcon.  I'll post it to the bug list.
Now posted as https://bugs.r-project.org/bugzilla3/show_bug.cgi?id=17325.

Duncan Murdoch