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<p class="MsoNormal"><span lang="EN-US">Hi erlang gurus,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">We’re developing erlang port driver that will send different terms to some processes from the separate threads using
<a name="driver_send_term"><span class="boldcode">driver_send_term</span></a><span class="boldcode">.<o:p></o:p></span></span></p>
<p class="MsoNormal"><span class="boldcode"><span lang="EN-US">Each native thread started in the port driver (by means of
<a name="erl_drv_thread_create">erl_drv_thread_create</a>) will be associated with only one erlang process and will send messages only to it.<o:p></o:p></span></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">As a rule the documentation for <span class="boldcode">
driver_send_term says that it’s not thread-safe when smp is disabled, so we have tested the driver with disabled smp support and found that from time to time it leads to segfaults.</span><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">So, the question is what is the proper way to make calls to
<span class="boldcode">driver_send_term (and driver_output_term) thread-safe? <o:p>
</o:p></span></span></p>
<p class="MsoNormal"><span class="boldcode"><span lang="EN-US">Will <a name="driver_pdl_lock">
driver_pdl_lock</a>, driver_pdl_unlock help? <o:p></o:p></span></span></p>
<p class="MsoNormal"><span class="boldcode"><span lang="EN-US">Will wrapping all the calls to driver_send_term (and driver_output_term) with
<a name="erl_drv_mutex_lock">erl_drv_mutex_lock</a> and erl_drv_mutex_unlock help?</span></span><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="color:black;mso-fareast-language:RU">Best Regards,<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="color:black;mso-fareast-language:RU">Sergey<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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