Log Message:
Changes 1.45:
        o fixed bug where setting the snaplen smaller than the minimum
          necessary to read the full headres would cause garbage to be
          fed into the pattern matcher
        o fixed unreported bug in IPv6/TCP packet length calculation
        o relocated the privilege-dropping routine to be invoked right
          before entering the packet processing loop, to prevent
          interference with necessary permissions to read or write
          dumpfiles/etc.
        o fixed integer overflow with the snaplen that resulted from
          an implicit signed/unsigned conversion
        o minor change to compensate for some broken compiler
          optimizers
        o fixed double-free race condition during ngrep termination
        o reworked packet length calculation in the main processing
          loop, improving performance and readability
        o simplified regex build logic in configure and Makefile
        o updated Win32 version to use config.h for preprocessor
          definitions instead of the Visual Studio project files,
          making manual tweaking and config of ngrep for Win32
          consistent with *NIX and more obvious
        o changed third-party Makefiles to properly clean up after
          themselves
        o added support for radiotap (IEEE802_11_RADIO)
        o changed ``-s 0'' invocation to mimic the equivalent of tcpdump