Raw I/O

Raw terminal I/O in ScarletDME

If you want to read from input without any character translation, it's necessary to disable some of the helpful processing that SD does. By default the input stream is converted from lower case to upper case (and vice versa), and Ctrl-C is processed as a break character. The output is formatted so as to require user to press <return> after each screen full of characters.

The following bit of code completely disables ALL formatting:-

  execute "TERM 32767,32767 NULL"
  echo off                          ;* Disables iput echoing
  prompt ""                         ;* Disables input prompt character
  junk=@(0, 0)                      ;* Disables output paging
  junk = junk                       ;* Supress compiler warning from above line
  term_settings = ttyget()          ;* get parameters
  term_settings<1> = 0              ;* Ctrl-C treated as the break key?  (PTERM BREAK mode)
  term_settings<2> = 0              ;* Case inversion on?  (PTERM CASE mode)
  ttyset term_settings              ;* set parameters

Once you've done this, it is still necessary to take care getting piped standard input (stdio) into Scarlet. Like this:-

     $include syscom err.h
     count = 0
     s = 1  ;* flag for more chars in stdin - we assume so at beginning
     loop
        count += 1
        string=keyin()
        if status() = er$eof then s = 0
        query_string := string
     while s
     while count < 1000000  ;* upper size limit 
     repeat

Glen is working on a single statement that the compiler can interpret to do the case conversion disable.

Ashley Chapman 2009-09-23