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copied!<p>Nice question. How perfect do you want to go? For an all singing all dancing solution, use asynchronous sockets, read all the data you can whenever you can, and whenever you get new data call some data processing function on the buffer.</p> <p>This allows you to do big reads. If you get a lot of commands pipelined you could potentially process them without having to wait on the socket again, thus increasing performance and response time.</p> <p>Do something similar on the write. That is the command processing function writes to a buffer. If there is data in the buffer then when checking sockets (select or poll) check for writeability and write as much as you can, remembering to only remove the bytes actually written from the buffer.</p> <p>Circular buffers work well in such situations.</p> <p>There are lighter simpler solutions. However this one is a good one. Remember that a server might get multiple connections and packets can be split. If you read from a socket into a buffer only to find you don;t have the data for a complete command, what do you do with the data you have already read? Where do you store it? If you store it in a buffer associated with that connection, then you might as well go the whole hog and just read into the buffer as described above in the first place.</p> <p>This solution also avoids having to spawn a separate thread for each connection - you can handle any number of connections without any real problems. Spawning a thread per connection is an unnecessary waste of system resources - except in certain circumstances where multiple threads would be recommended anyway, and for that you can simply have worker threads to execute such blocking tasks while keeping the socket handling single threaded.</p> <p>Basically I agree with what you say Beej says, but don't read tiddly bits at a time. Read big chunks at a time. Writing a socket server like this, learning and designing as I went along based on a tiny bit of socket experience and man pages, was one of the most fun projects I have ever worked on, and very educational.</p>

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