* platform/example is now a "stub" platform - it should compile anywhere, but

[pdclib] / platform / posix / Readme.txt

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+$Id$
+
+"Example" Platform Overlay
+==========================
+
+This is an example platform overlay, as described in the main Readme.txt of
+this archive. For ease of development, it applies (and tests) correctly on the
+machine of the author; no other guarantees can be given.
+It should give you a good idea of what is REQUIRED to make a copy of PDCLib
+work. There is a lot more you could do, and even some things you SHOULD do, in
+order to experience anything but abysmal performance:
+
+- Read / write operations on binary streams, and even on text streams for
+  machines that do not do any text conversion, can be made much more efficient
+  by using some sort of page buffer instead of the linear buffer implemented
+  here. It requires some special and platform-dependent manipulations, though,
+  which is why it is not done by default.
+
+- Anything relating to floating point logic is written in generic C. While
+  this is (hopefully) highly portable and should get you started on your
+  platform of choice, it is also highly inefficient and should be replaced by
+  inline assembly. Just make sure that your assembly keeps all the promises
+  the C library makes.
+