[tlbuild] predefined symbols

[Bruno Haible]

Akira Kakuto wrote:
> if you teach me VAR_ONLY_DEFINED_IN_SOLARIS

You can recognize Solaris through
  #if defined __sun

More generally, you can find the predefined macros of many systems at
http://predef.sf.net

On platforms where GCC is the only compiler, you can find the symbols
through the command
  : | gcc -E -dM -
Few of these are specific to the OS, of course. Most of these symbols are
about other things.

Bruno