showConnections {base} | R Documentation |
Display aspects of connections.
showConnections(all=FALSE) getConnection(what) closeAllConnections() stdin() stdout() stderr()
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
showConnections . |
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.
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
.
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" close(getConnection(3)) showConnections()