| showConnections {base} | R Documentation |
Display Connections
Description
Display aspects of connections.
Usage
showConnections(all=FALSE)
getConnection(what)
closeAllConnections()
stdin()
stdout()
stderr()
Arguments
all |
logical: if true all connections, including closed ones and the standard ones are displayed. If false only open user-created connections are included. |
what |
integer: a row number of the table given by
|
Details
stdin(), stdout() and stderr() are standard
connections corresponding to input, output and error on the console
respectively (and not necessarily to file streams). They are text-mode
connections of class "terminal" which cannot be opened or
closed, and are read-only, write-only and write-only respectively.
The stdout() connection can be re-directed by sink.
showConnections returns a matrix of information. If a
connection object has been lost or forgotten, getConnection
will take a row number from the table and return a connection object
for that connection, which can be used to close the connection,
for example.
closeAllConnections closes all open user connections.
Value
stdin(), stdout() and stderr() return connection
objects.
showConnections returns a character matrix of information with
a row for each connection, by default only for open non-standard connections.
getConnection returns a connection object, or NULL.
See Also
connections
Examples
showConnections(all = TRUE)
textConnection(letters)
# oops, I forgot to record that one
showConnections()
# class description mode text isopen can read can write
#3 "letters" "textConnection" "r" "text" "opened" "yes" "no"
## Not run: close(getConnection(3))
showConnections()