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<p class="MsoNormal">Could you perhaps elaborate on your reply a bit? The RT development environment (running in kernel mode) offers only a memory mapped interface besides the aforementioned UDP/TCP option for communication between the RT modules and user
mode applications. I believe “exposing the interface” would require me to both make an interface from scratch and then wrap it as a port driver or NIF to get it into the BEAM. Aside from some arbitrary handshaking interface via registers I could imagine
passing strings via fixed length character buffers but I will still need some form of encoding/decoding… which is how I ended up looking at the ei library.<o:p></o:p></p>
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<p class="MsoNormal">Also, most of what I have read regarding Erlang seems to favor ports over drivers and NIFs as they better align with the Erlang philosophy but I am too new to all this to really know when each is preferred.<o:p></o:p></p>
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<p class="MsoNormal">Thanks much,<o:p></o:p></p>
<p class="MsoNormal">Brett<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> Albin Stigö <albin.stigo@gmail.com> <br>
<b>Sent:</b> Thursday, September 17, 2020 9:32 AM<br>
<b>To:</b> Max Lapshin <max.lapshin@gmail.com><br>
<b>Cc:</b> Brett Hemes <brhemes@mmm.com>; Erlang Questions <erlang-questions@erlang.org><br>
<b>Subject:</b> [EXTERNAL] Re: Using (stripped down ei.h) with generic TCP instead of ports<o:p></o:p></p>
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<p class="MsoNormal">I would expose the kernel code through a char or block device driver. There are already many facilities in most kernels for effective communication with userpace. a<o:p></o:p></p>
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<p class="MsoNormal">After all, that's the whole point of a kernel...<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">--Albin<o:p></o:p></p>
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<p class="MsoNormal">On Thu, Sep 17, 2020, 16:00 Max Lapshin <<a href="mailto:max.lapshin@gmail.com" target="_blank">max.lapshin@gmail.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Your idea is ok. Just strip everything you don't need from ei and it will work for you.<o:p></o:p></p>
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<p class="MsoNormal">As for me, I like enif api more, but Sverker has pointed that I'm misuing it inside drivers and it may break once =)<o:p></o:p></p>
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