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The Linux console is a system console internal to the Linux kernel (a system console is the device which receives all kernel messages and warnings and which allows logins in single user mode).〔(【引用サイトリンク】title=config VT_CONSOLE: Support for console on virtual terminal )〕 The Linux console provides a way for the kernel and other processes to send text output to the user, and to receive text input from the user. The user typically enters text with a computer keyboard and reads the output text on a computer monitor. The Linux kernel supports virtual consoles - consoles that are logically separate, but which access the same physical keyboard and display.〔(【引用サイトリンク】title=config VT: Virtual terminal )〕 The Linux console (and Linux virtual consoles) are implemented by the VT subsystem of the Linux kernel, and do not rely on any user space software.〔 This is in contrast to a terminal emulator, which is a user space process that emulates a terminal, and is typically used in a graphical display environment. The Linux console was one of the first features of the kernel and was originally written by Linus Torvalds in 1991 (see history of Linux). There are two main implementations: framebuffer and text mode. The framebuffer implementation is the default in modern Linux distributions, and together with kernel mode setting, provides kernel-level support for display hardware and features such as showing graphics while the system is booting.〔(【引用サイトリンク】title=The Framebuffer Console )〕 The legacy text mode implementation was used in PC-compatible systems with CGA, EGA, MDA and VGA graphics cards. Non-x86 architectures used framebuffer mode because their graphics cards did not implement text mode.〔 The Linux console uses fixed-size bitmap, monospace fonts, usually defaulting to 8x16 pixels per character.〔 The Linux console is an optional kernel feature, and most embedded Linux systems do not enable it. These systems typically provide an alternative user interface (e.g. web based), or boot immediately into a graphical user interface and use this as the primary means of interacting with the user. Other implementations of the Linux console include the Braille console to support refreshable Braille displays.〔(【引用サイトリンク】title=Documentation/braille-console.txt )〕 and the serial port console.〔(【引用サイトリンク】title=Documentation/serial-console.txt )〕 == Purpose == The Linux console provides a way for the kernel and other processes to output text-based messages to the user, and to receive text-based input from the user. In Linux, several devices can be used as system console: a 〔(【引用サイトリンク】url=http://cateee.net/lkddb/web-lkddb/VT_CONSOLE.html )〕 virtual terminal,〔(【引用サイトリンク】url=http://cateee.net/lkddb/web-lkddb/SERIAL_CONSOLE.html )〕 serial port,〔(【引用サイトリンク】url=http://cateee.net/lkddb/web-lkddb/USB_SERIAL_CONSOLE.html )〕 USB serial port,〔(【引用サイトリンク】url=http://cateee.net/lkddb/web-lkddb/VGA_CONSOLE.html )〕 VGA in text-mode, framebuffer. Some modern Linux-based systems have deprecated kernel based text-mode input and output, and instead show a graphical logo or progress bar while the system is booting, followed by the immediate start of a graphical user interface (e.g. the X.Org Server on desktop distributions, or SurfaceFlinger on Android). During kernel boot, the console is commonly used to display the boot log of the kernel. The boot log includes information about detected hardware, and updates on the status of the boot procedure. At this point in time, the kernel is the only software running, and hence logging via user-space (e.g. syslog) is not possible, so the console provides a convenient place to output this information. Once the kernel has finished booting, it runs the init process (also sending output to the console), which handles booting of the rest of the system including starting any background daemons. After the ''init'' boot process is complete, the console will be used to multiplex multiple virtual terminals (accessible by pressing Ctrl-Alt-F1, Ctrl-Alt-F2 etc., Ctrl-Alt-LeftArrow, Ctrl-Alt-RightArrow, or using ''chvt''). On each ''virtual terminal'', a getty process is run, which in turn runs ''/bin/login'' to authenticate a user. After authentication, a command shell will be run. Virtual terminals, like the console, are supported at the Linux kernel level.〔(【引用サイトリンク】title=console(4) - Linux man page: console - console terminal and virtual consoles )〕 The Linux console implements a terminal type of "linux" and the escape sequences it uses are in the ''console_codes'' man page. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Linux console」の詳細全文を読む スポンサード リンク
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