R Package Building Question

On Wed, 1 Mar 2000, Brett Presnell wrote:

1. If this file is named R/sta4504 (with no extension), then when I
build the package (under Solaris), create a zip file and install the
package on a Windows PC, it works fine.  However, under Solaris,
R INSTALL sta4504 hangs and does not complete the installation of the
package.

2. If this file is named R/sta4504.R, then the package installs and
works fine on the Solaris machine, but the same package is not
recognized as even existing by R under Windows.

I notice that most (all?) of the contributed packages leave off the
extension, in spite of the advice to the contrary (at least to my
reading) in Section 1.1.3 of "Writing R Extensions", and they all work
on both platforms.  I don't remember ever seeing this come up on the
list, so what am I missing?

What you're missing is that Unix packages are source code and Windows
packages are compiled. It's less obvious when there isn't any C or Fortran
code.  This is because typical Windows installations lack not only
compilers for C and Fortran but also the tools to process help pages.

In source form the package/R directory contains one or more files with
extensions .R (or .r, .q or various other possibilities), the package/src
directory has C or Fortran source code, package/man has .Rd files.

In compiled form package/R has a single file whose name is the name of the
package, the /src subdirectory is replaced by a /libs subdirectory with a
shared library, the /man subdirectory is replaced by one or more
subdirectories with various compiled help files.

So, sta4504.tgz should be a source package, with extensions, sta4504.zip
should be a compiled package, with no extensions.  There would be other 
differences if you had help pages for the functions.