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()
and stderr()
connections 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 (and destroys) all open user
connections, restoring all sink
diversions as it does so.
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" ## Not run: close(getConnection(3)) showConnections()