From: james.harris.1@gmail.com   
      
   On 14/07/2021 14:56, James Harris wrote:   
      
   > Is there already a good standard way to interface with a textual   
   > display? What I'm looking for is a pre-defined set of calls which I can   
   > just implement rather than having to design from scratch.   
      
   As a sub topic, I gather there are standard ways to implement a   
   'terminal' which will work with both a VDU and a machine which prints   
   characters on paper instead of a screen.   
      
   For example, with paper a backspace cannot delete the previous character   
   (unless it's a space) but there are other options. The terminal could:   
      
   1. print a certain character to indicate the backspace such as ~ in   
      
      prant~~~int   
      
   (to form the word "print")   
      
   2. back up and overwrite any character which is no longer present in the   
   buffer as with   
      
      pr@@@int   
      
   where @ represents some form of overwritten characters.   
      
   Similarly, on a VDU a backspace could, effectively, be written as   
      
      backspace, space, backspace   
      
   but in any case the point is that there's a translation between what a   
   program would work with (the backspace in this example) and how it gets   
   rendered on the terminal.   
      
   I don't anticipate really using a paper-feed teletype, and backspace is   
   not the only issue but I would still like there to be a translation   
   layer between a program and whatever is used as a text-display device.   
      
   I know there are various standards for terminals but my experience of   
   them has - literally for decades - shown that it's difficult if not   
   impossible for a user to get both ends (OS and terminal) to work   
   together consistently.   
      
   On top of that I gather there are various standards for how terminal IO   
   translations can be specified - such as what text to print in   
   bold/bright, where a certain piece of text should appear, how to ask for   
   a line to be reprinted, etc, but I know almost nothing about them.   
      
   Hence the question: would you recommend any particular translation layer   
   (between OS and the gamut of terminal devices) or would it be better,   
   these days, to design one's own?   
      
      
   --   
   James Harris   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)