src/library/base/R/sink.R

#  File src/library/base/R/sink.R
#  Part of the R package, https://www.R-project.org
#
#  Copyright (C) 1995-2016 The R Core Team
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  A copy of the GNU General Public License is available at
#  https://www.R-project.org/Licenses/

sink <- function(file=NULL, append = FALSE, type = c("output", "message"),
                 split=FALSE)
{
    type <- match.arg(type)
    if(type == "message") {
        if(is.null(file)) file <- stderr()
        else if(!inherits(file, "connection") || !isOpen(file))
           stop("'file' must be NULL or an already open connection")
        if (split) stop("cannot split the message connection")
        .Internal(sink(file, FALSE, TRUE, FALSE))
    } else {
        closeOnExit <- FALSE
        if(is.null(file)) file <- -1L
        else if(is.character(file)) {
            file <- file(file, if(append) "a" else "w")
            closeOnExit <- TRUE
        } else if(!inherits(file, "connection"))
            stop("'file' must be NULL, a connection or a character string")
        .Internal(sink(file, closeOnExit, FALSE,split))
    }
}

sink.number <- function(type = c("output", "message"))
{
    type <- match.arg(type)
    .Internal(sink.number(type != "message"))
}