mirror of https://github.com/20kdc/OC-KittenOS.git
115 lines
2.7 KiB
Plaintext
115 lines
2.7 KiB
Plaintext
The "svc-t" program / "x.neo.pub.t"
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permission makes up the terminal
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subsystem for KittenOS NEO.
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--- THEORETICAL TERMINALS MODEL ---
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The theoretical model for terminals
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in KittenOS NEO is a TELNET client,
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using the non-standard behavior of
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treating a lack of remote echo as
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meaning 'local line editing'.
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To prevent code size going too far,
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the shipped terminal supports:
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1. Built-in history as part of the
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line editing functionality
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2. ANSI.SYS-compatible display, but
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no support for attributes.
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If you really want full support,
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write a better terminal application.
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A process starting another process
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connected to the same terminal is
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advised to wait for that process to
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die before continuing reading input.
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The controlling process is whichever
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process is supposed to be accepting
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user input. This is contextual, and
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there is no mechanism to control
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this explicitly.
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The controlling process should show
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text in response to any user input,
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or at least provide some form of
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acknowledgement that user input has
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been received.
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For convenience, terminal echo is on
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by default; this is easily remedied.
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--- ACTUAL USAGE OF TERMINALS ---
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Access control on terminals is looser
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than for most permissions, as it has
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to be able to be 'sublet' in some
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cases, including events.
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As such, the secret flag is set for
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terminal registration.
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A terminal program is given a string
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argument for the ID of the terminal
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to connect to.
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A terminal always has an ID beginning
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with "x.neo.pub.t/". ALWAYS CHECK.
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Requiring the responsible access
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connects to the terminal. All
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terminal programs SHOULD check for
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the death of their parent terminal
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(via the k.procdie event) and
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self-destruct accordingly.
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A program may start svc-t directly.
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In this case, it must pass a function
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(resTbl) and may pass a title.
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When the terminal has shown, the
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function provided is called with a
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table as follows:
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access = "x.neo.pub.t/<...>"
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close = function (): close terminal
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The k.kill permission and the close
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function are the only ways for a
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program to kill a terminal, and the
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close function is only given to the
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creating process.
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In either case, when the access has
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been acquired, the following API is
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presented:
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id = "x.neo.pub.t/<...>"
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pid = <The terminal's PID.>
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write = function (text): Writes the
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TELNET data to the terminal.
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User input is provided in events:
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<id>, "data", <data>
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TELNET commands are provided in:
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<id>, "telnet", <data>
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There is a total of one TELNET
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command per event, unpadded.
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Notably, intermixing the data part
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of the data/telnet events in order
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produces the full terminal-to-server
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TELNET stream.
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-- This is released into
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the public domain.
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-- No warranty is provided,
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implied or otherwise.
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