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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Do not modify this file since it was automatically generated from:
%
% pushBackupFile.R
%
% by the Rdoc compiler part of the R.oo package.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\name{pushBackupFile}
\alias{pushBackupFile.default}
\alias{pushBackupFile}
\title{Appends a backup suffix to the pathname}
\usage{
\method{pushBackupFile}{default}(filename, path=NULL, suffix=".bak", isFile=TRUE,
onMissing=c("ignore", "error"), copy=FALSE, overwrite=TRUE, ..., verbose=FALSE)
}
\description{
Appends a backup suffix to the pathname and, optionally, renames an existing file accordingly.
In combination with \code{\link{popBackupFile}}(), this method is useful
for creating a backup of a file and restoring it.
}
\arguments{
\item{filename}{The filename of the file to backup.}
\item{path}{The path of the file.}
\item{suffix}{The suffix to be appended.}
\item{isFile}{If \code{\link[base:logical]{TRUE}}, the file must exist and will be renamed
on the file system. If \code{\link[base:logical]{FALSE}}, it is only the pathname string
that will be modified. For details, see below.}
\item{onMissing}{A \code{\link[base]{character}} string specifying what to do if the
file does not exist.}
\item{copy}{If \code{\link[base:logical]{TRUE}}, an existing original file remains after
creating the backup copy, otherwise it is dropped.}
\item{overwrite}{If \code{\link[base:logical]{TRUE}}, any existing backup files are overwritten,
otherwise an exception is thrown.}
\item{...}{Not used.}
\item{verbose}{A \code{\link[base]{logical}} or \code{\link{Verbose}}.}
}
\value{
Returns the pathname with the suffix appended.
}
\examples{
# Create a file
pathname <- file.path(tempdir(), "foobar.txt")
cat(file=pathname, "File v1\n")
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# (a) Backup and restore a file
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# Turn it into a backup file
pathnameB <- pushBackupFile(pathname, verbose=TRUE)
print(pathnameB)
# Restore main file from backup
pathnameR <- popBackupFile(pathnameB, verbose=TRUE)
print(pathnameR)
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# (b) Backup, create a new file and frop backup file
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# Turn it into a backup file
pathnameB <- pushBackupFile(pathname, verbose=TRUE)
print(pathnameB)
# Create a new file
cat(file=pathname, "File v2\n")
# Drop backup because a new main file was successfully created
pathnameR <- popBackupFile(pathnameB, verbose=TRUE)
print(pathnameR)
}
\author{Henrik Bengtsson}
\seealso{
\code{\link{popBackupFile}}().
}
\keyword{utilities}
\keyword{programming}
\keyword{IO}
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