through an API.  It is
also possible to access information about a flag, such as its default
value and help-string.  A <code>FlagSaver</code> makes it easy to
modify flags and then automatically undo the modifications later.
Finally, there are somewhat unrelated, but useful, routines to easily
access parts of <code>argv</code> outside main, including the program
name (<code>argv[0]</code>).</p>

<p>For more information about these routines, and other useful helper
methods such as <code>gflags::SetUsageMessa