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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Do not modify this file since it was automatically generated from:
%
% withSink.R
%
% by the Rdoc compiler part of the R.oo package.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\name{withSink}
\alias{withSink}
\title{Evaluate an R expression while temporarily diverting output}
\description{
Evaluate an R expression while temporarily diverting output.
}
\usage{
withSink(expr, file, append=FALSE, type=c("output", "message"), substitute=TRUE,
envir=parent.frame())
}
\arguments{
\item{expr}{The R expression to be evaluated.}
\item{file}{A writable \code{\link[base:connections]{connection}} or a \code{\link[base]{character}} string naming the
file to write to.}
\item{append}{If \code{\link[base:logical]{TRUE}}, the diverted output is appended to the file,
otherwise not.}
\item{type}{A \code{\link[base]{character}} string specifying whether to divert output
sent to the standard output or the standard error.
See \code{\link[base]{sink}}() for details.}
\item{substitute}{If \code{\link[base:logical]{TRUE}}, argument \code{expr} is
\code{\link[base]{substitute}()}:ed, otherwise not.}
\item{envir}{The \code{\link[base]{environment}} in which the expression should be evaluated.}
}
\value{
Returns the results of the expression evaluated.
}
\details{
Upon exit (also on errors), this function will close the requested
"sink". If additional sinks (of any type) where also opened during
the evaluation, those will also be closed with a warning.
}
\author{Henrik Bengtsson}
\examples{
# Divert standard output
pathname <- tempfile(fileext=".output.txt")
res <- withSink(file=pathname, {
print(letters)
})
mcat(readLines(pathname), sep="\n")
# Divert standard error/messages
pathname <- tempfile(fileext=".message.txt")
res <- withSink(file=pathname, type="message", {
mprint(LETTERS)
})
mcat(readLines(pathname), sep="\n")
}
\seealso{
Internally, \code{\link[base]{sink}}() is used to divert any output.
}
\keyword{IO}
\keyword{programming}
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