Dynamic visualizations: On ‘non-canonical’ keyboard-input and terminal escape-sequences for visualization effects includes Our course’s theme, Two ‘dynamic visualizations’, Some application tools, The ‘tty’ interface, The ‘c_lflag’ field. | Dynamic visualizations On ‘non-canonical’ keyboard-input and terminal escape-sequences for visualization effects Our course’s theme Using the computer to study the computer Two ‘dynamic visualizations’ • Showing the Linux kernel’s algorithm for setting up ‘permanent kernel mappings’ • Showing the dual-CPUs’ responses to device-interrupts and CPU-exceptions Some application tools • We need to modify the terminal-console’s normal way of processing keyboard-input and of displaying its line-at-a-time output • ANSI terminal escape-sequences allow page-oriented output (., left-and-right, up-and-down), control of cursor-visibility and of character-attributes (., colors) The ‘tty’ interface • • • • ‘tty’ is an acronyn for ‘TeleTYpe’ terminal Such devices have a keyboard and screen Behavior emulates technology from 1950s Usually a tty operates in ‘canonical’ mode: – Each user-keystroke is ‘echoed’ to screen – Some editing is allowed (., backspace) – The keyboard-input is internally buffered – The -key signals an ‘end-of-line’ – Programs receive input .
