[Rd] Borland C++ and [R] dyn.load() for windows
Prof Brian Ripley
ripley at stats.ox.ac.uk
Wed Oct 26 23:20:57 CEST 2005
On Wed, 26 Oct 2005, huanyu zhou wrote:
> I compiled a C program file on Borland C++ 5.5 compiler to get one dll output
> (as instructed in the file readme.package).
> The C program file is just the example on page 31 of "writing R extensions":
> void convolve(double *a, int *na, double *b, int *nb, double *ab)
> int i, j, nab = *na + *nb - 1;
> for(i = 0; i < nab; i++)
> ab[i] = 0.0;
> for(i = 0; i < *na; i++)
> for(j = 0; j < *nb; j++)
> ab[i + j] += a[i] * b[j];
> I used
> "bcc32 -Ic:\Borland\bcc55\include -Lc:\Borland\bcc55\Lib -u- -6 -O2 -WDE
> to get "convolve.dll". It seemed fine.
> When I used dyn.load("C:\\Borland\\BCC55\\Bin\\convolve.dll") in R (Version
> 2.0.1 ), it seemed fine also, no warning or error messages. However, when I
> used is.loaded("convolve") to check if it was loaded, it showed "False".
> I am working on winXP.
> What could be the possible reason for that?
The usual reason is that no symbols are exported from the DLL: please use
pedump -e to check. I don't see any evidence that you asked for any to be
and the example in README.packages uses __declspec(dllexport) in the
original source. You are advised to look up the reference given there for
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595
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