移植 - 6. 为 10.4 做准备
6.1 Perl
    /usr/bin/perl is now perl 5.8.6; the
    architecture string is still "darwin-thread-multi-2level".
  
6.2 New symbol definitions
    Mac OS X 10.4 has changed the types of many symbols. If you
    previously set a type explicitly, for example,
    defining socklen_t as int, that
    definition may no longer be correct.
  
6.3 New builtin system libraries
    The poll() function in Mac OS X 10.3 was actually an
    emulation implemented using select(). In Mac OS X
    10.4, poll() is a real function implemented in the
    kernel, however it is broken when used with sockets. Consider
    ignoring the system's poll() completely. Fink's glib2
    package has been patched to use a fully functional emulation, so
    it is safe to use that library's implementation of poll-like
    functions.