Platform specific sources

[dog.ee.lbl.gov!hellgate.utah.edu!cs.utexas.edu!zaphod.mps.ohio-state.edu! swrinde!ctcvax.ccf.swri.edu!trident!tim@ucbvax.Berkeley.EDU (Timothy J. Barton]

Is there a "superior" method for supporting platform specific
features in the same source code using Ada?  I would prefer if
the method didn't require a tool which doesn't come with the
standard Ada toolset (such as cpp, etc.).  I am developing Ada
software which will eventually run on a PC using Alsys, a Sun
using SunAda (VADS), and a DEC.  There will be host OS specific
code which in C would normally be handled via cpp.  Should I
ftp the Ada source for an "Ada cpp" and then build it for each
of my development platforms?  What is the standard practice in
the Ada world?

Sorry for my ignorance, I am a longtime C'er and didn't see
anything in the FAQ.  Thanks in advance.

----------------------------------------------------------------------------
Timothy J. Barton                         tim@trident.datasys.swri.edu
Senior Research Analyst                   (512) 522-3540
Southwest Research Institute (SwRI)       (512) 522-5499  (Fax)   
San Antonio, Texas  78228-0510