########################################################################/**
 # @RdocFunction copyCel
 #
 # @title "Copies a CEL file"
 #
 # \description{
 #  @get "title".
 #
 #  The file must be a valid CEL file, if not an exception is thrown.
 # }
 #
 # @synopsis
 #
 # \arguments{
 #  \item{from}{The filename of the CEL file to be copied.}
 #  \item{to}{The filename of destination file.}
 #  \item{overwrite}{If @FALSE and the destination file already exists,
 #    an exception is thrown, otherwise not.}
 #  \item{...}{Not used.}
 # }
 #
 # \value{
 #   Return @TRUE if file was successfully copied, otherwise @FALSE.
 # }
 #
 # \seealso{
 #   @see "isCelFile".
 # }
 #

 # @author "HB"

 #
 # @keyword programming
 # @keyword file
 # @keyword IO
 # @keyword internal
 #**/#######################################################################
 copyCel <- function(from, to, overwrite=FALSE, ...) {
   # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
   # Validate arguments
   # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
   # Argument 'from':
   if (!file.exists(from)) {
     stop("Cannot copy CEL file. File not found: ", from);
   }
 
   # Argument 'to':
   if (file.exists(to) && !overwrite) {
     stop("Cannot copy CEL file. File already exists: ", to);
   }
 
   # Check if a CEL file
   if (!isCelFile(from)) {
     stop("Cannot copy CEL file. Source file is not a valid CEL file: ", from);
   }
 
   file.copy(from, to, overwrite=overwrite);
 }
 
 
 ############################################################################
 # HISTORY:
 # 2006-07-10
 # o Added check with isCelFile().
 # 2006-06-22
 # o Created.
 ############################################################################