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<title>Does Boost.Log support logging at process initialization and termination?</title>
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<div class="titlepage"><div><div><h3 class="title">
<a name="log.rationale.init_term_support"></a><a class="link" href="init_term_support.html" title="Does Boost.Log support logging at process initialization and termination?">Does Boost.Log support
      logging at process initialization and termination?</a>
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<p>
        It should be fine to use logging during the application initialization (i.e.
        before <code class="computeroutput"><span class="identifier">main</span><span class="special">()</span></code>
        starts). But there are a number of known problems with Boost.Log that prevent
        it from being used at process termination (i.e. after the <code class="computeroutput"><span class="identifier">main</span><span class="special">()</span></code> function returns), so the official answer
        to the second part is no. It may work though, in some very restricted setups,
        if several rules are followed:
      </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
            Do not create any objects at process termination, including loggers,
            attributes or sinks. Try to create and cache the required objects as
            soon as the application starts (maybe even before <code class="computeroutput"><span class="identifier">main</span><span class="special">()</span></code> starts).
          </li>
<li class="listitem">
            Do not use global loggers at process termination.
          </li>
<li class="listitem">
            Do not call <code class="computeroutput"><span class="identifier">logging</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">get</span><span class="special">()</span></code>
            at process termination. Get that pointer as early as possible and keep
            it until the process terminates.
          </li>
<li class="listitem">
            Do not use named scopes in termination code.
          </li>
</ul></div>
<p>
        These rules don't guarantee that the library will work in termination context
        but they may help to avoid problems. The library will get improved to support
        this use case better.
      </p>
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      Semashev<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>).
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