A console driver from my ISO scratch work.

Console.h

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+static_assert( __cplusplus > 2020'00 );
+
+#pragma once
+
+// These are some terminal/console control primitives.
+// There are several "modern" terminal assumptions built
+// into this library.
+//
+// As long as this works on most (all?) modern terminal emulators, this should be
+// fine.
+
+namespace Alepha::inline Cavorite  ::detail::  console
+{
+	inline namespace exports {}
+
+	namespace exports
+	{
+		struct ScreenSize;
+		struct CursorPosition;
+
+		class Console;
+
+		Console &console() noexcept;
+
+		struct SGR_String
+		{
+			std::string code;
+		};
+
+		inline auto
+		operator ""_sgr( const char *const p, const std::size_t sz )
+		{
+			return SGR_String{ { p, p + sz } };
+		}
+
+		enum class BasicTextColor : int;
+		enum class TextColor : int;
+
+		struct Style
+		{
+			std::string name;
+
+			TotalOrder operator <=> ( const Style & ) const= default;
+		};
+		std::ostream &operator << ( std::ostream &, const Style & );
+
+		Style createStyle( const std::string &name, const SGR_String &style );
+		bool styleVarSet( const std::string &name );
+
+		enum ResetStyle { resetStyle };
+		std::ostream &operator << ( std::ostream &, ResetStyle );
+
+		// TODO: Move this to its own library.
+		const std::string &applicationName();
+		void setApplication( std::string name );
+	}
+
+	struct exports::ScreenSize
+	{
+		int rows;
+		int columns;
+	};
+
+	struct exports::CursorPosition
+	{
+		int x;
+		int y;
+	};
+
+	class exports::Console
+	{
+		private:
+			class Impl;
+			std::unique_ptr< Impl > impl;
+			Impl &pimpl() noexcept { return *impl; }
+			const Impl &pimpl() const noexcept { return *impl; }
+
+			std::ostream &csi();
+
+		public:
+			// A console object can only be constructed on a raw UNIX file descriptor.
+			explicit Console( int fd );
+
+			enum Mode;
+
+			Mode getMode() const;
+
+			int getScreenWidth();
+			int getScreenHeight();
+
+			// Althought this could be implemented by combining the above observers,
+			// there are more efficient ways to implement this, thus we actually
+			// keep them separate.
+			ScreenSize getScreenSize();
+
+			void hideCursor();
+			void showCursor();
+
+			// Pushes the current mode (raw or normal) onto the stack.
+			void setRaw();
+
+			// A nonblock mode is used to prevent terminal IO from blocking.  This helps with keypress driven
+			// programs.  This is its own raw mode.
+			void setNoblock();
+
+			// The Console object maintains an internal stack of the last terminal modes it set and how to
+			// revert tothe previous.  There is no arbitrary limit on this stack size.  Calling this with
+			// no previous modes is a no-op.
+			void popTermMode();
+
+			// Line kill functions keep the cursor where it is, but erase the specified text on the line.
+			void killLine();
+			void killLineHead();
+			void killLineTail();
+
+			// One should avoid calling these, as some internals may also use these hardware functions.
+			// It is better to use `gotoXY` and `getXY` to save/restore cursor positions.  One should
+			// maintain a software stack (as a caller) of cursor positions, if necessary.
+			void saveHardwareCursor();
+			void restoreHardwareCursor();
+
+			void gotoX( int x );
+			void gotoY( int y );
+			void gotoXY( int x, int y );
+
+			int getX();
+			int getY();
+			CursorPosition getXY();
+
+			void cursorUp( unsigned amt= 0 );
+			void cursorDown( unsigned amt= 0 );
+
+			void cursorLeft( unsigned amt= 0 );
+			void cursorRight( unsigned amt= 0 );
+
+			void clearScreen(); // `console` library does direct cursor control, so this won't return the cursor to 1,1.
+	};
+
+	namespace exports
+	{
+		[[nodiscard]] SGR_String resetTextEffects();
+
+		[[nodiscard]] SGR_String setBlink();
+
+		[[nodiscard]] SGR_String setFGColor( BasicTextColor fg );
+		[[nodiscard]] SGR_String setBGColor( BasicTextColor bg );
+		[[nodiscard]] SGR_String setColor( BasicTextColor fg, BasicTextColor bg );
+
+		[[nodiscard]] SGR_String setExtFGColor( TextColor fg );
+		[[nodiscard]] SGR_String setExtBGColor( TextColor fg );
+		[[nodiscard]] SGR_String setExtColor( TextColor fg, TextColor bg );
+
+		// Basic color wrapping aliases:
+		[[nodiscard]] inline SGR_String setExtFgColor( const BasicTextColor fg ) { return setExtFgColor( static_cast< TextColor >( fg ) ); }
+		[[nodiscard]] inline SGR_String setExtBgColor( const BasicTextColor bg ) { return setExtBgColor( static_cast< TextColor >( bg ) ); }
+
+		[[nodiscard]] inline SGR_String setExtColor( const      TextColor fg, const BasicTextColor bg ) { return setExtColor(                         ( fg ), static_cast< TextColor >( bg ) ); }
+		[[nodiscard]] inline SGR_String setExtColor( const BasicTextColor fg, const TextColor      bg ) { return setExtColor( static_cast< TextColor >( fg ),                         ( bg ) ); }
+		[[nodiscard]] inline SGR_String setExtColor( const BasicTextColor fg, const BasicTextColor bg ) { return setExtColor( static_cast< TextColor >( fg ), static_cast< TextColor >( bg ) ); }
+
+		[[nodiscard]] SGR_String setFgTrueColor( int rgb );
+		[[nodiscard]] SGR_String setFgTrueColor( int r, int g, int b )
+
+		[[nodiscard]] SGR_String setBgTrueColor( int rgb );
+		[[nodiscard]] SGR_String setBgTrueColor( int r, int g, int b )
+
+		void sendSGR( std::ostream &os, SGR_String );
+	}
+}