The R Project SVN R

% File src/library/base/man/getCallingDLL.Rd
% Part of the R package, http://www.R-project.org
% Copyright 1995-2007 R Core Development Team
% Distributed under GPL 2 or later

\name{getCallingDLL}
\alias{getCallingDLL}
\alias{getCallingDLLe}
\title{Compute DLL for native interface call}
\description{

  This is an internal function that is called
  from R's C code to determine the
  enclosing name space of a .C/.Call/.Fortran/.External
  call which has no PACKAGE argument.
  If the call has been made from a function within a name space,
  then we can find the DLL associated with that name space.
  The purpose of this is to avoid having to use the PACKAGE
  argument in these native calls and so better support versions
  of packages.

  This is an internal function that may be migrated to internal C
  code in the future and so should not be used by R programmers.
}
\usage{
getCallingDLL(f = sys.function(-1), doStop = FALSE)
getCallingDLLe(e)
}
\arguments{
  \item{f}{the function whose name space and DLL are to be found.
    By default, this is the current function being called which
    is the one in which the native routine is being invoked.}
  \item{doStop}{a logical value indicating whether failure to find
    a name space and/or DLL is an error (\code{TRUE}) or not
    (\code{FALSE}).
    The default is \code{FALSE} so that when this is called
    because there is no PACKAGE argument in a \code{\link{.C}},
    \code{\link{.Call}}, \code{\link{.Fortran}}, \code{\link{.External}}
    call,  no error occurs and
    the regular lookup is performed by searching all DLLs in order.
  }
  \item{e}{an environment.}
}

\seealso{
\code{\link{.C}},
\code{\link{.Call}},
\code{\link{.Fortran}},
\code{\link{.External}}
}
\examples{
if(exists("ansari.test"))
   getCallingDLL(ansari.test)
}
\keyword{programming}