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    <p>It really depends. The two major ways would be threaded (like you mentioned) and evented.</p> <p>Threaded code is tricky because you can easily introduce race conditions. Code that you tested a million times could occasionally stumble and do the wrong thing after working for days or weeks or years. It's hard to 'prove' that things will always behave correctly. Seemingly trivial things like "i++" suddenly become leaky abstractions. (See <a href="https://stackoverflow.com/questions/6052768/why-is-i-not-thread-safe-on-a-single-core-machine">why is i++ not thread safe on a single core machine?</a> )</p> <p>The other alternative is evented programming. Basically, you have a main loop that does a select() on all your file handles. Anything that is ready gets looked at, and you try to read/write as many bytes as you can without blocking. (pass O_NONBLOCK). There are two tricky parts: 1) you must never do long calculations without having a way to yield back to the main loop, and 2) you must never do a blocking operation (where the kernel stops your process waiting for a read or write).</p> <p>In practice, most programs don't have long computations and it's easier to audit a small amount of your code for blocking calls than for races. (Although doing DNS without blocking is trickier than it should be.)</p> <p>The upside of evented code is that there's no need for locking (no other threads to worry about) and it wastes less memory (in the general case where you're creating lots of threads.)</p> <p>Most likely, you want to use a serial lib. termios processing is just overhead and a chance for stray bytes to do bad things.</p>
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    1. POBest practice to implement fixed byte serial protocol in C++?
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    1. COThank you for the overview. What I didn't write in the question, this communication interface will be part of a project where there are already different threads. Therefore the event loop is not an option this time, but I will keep it in mind.
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