Artifact 648969222c387e41714b634c51cca57415bc757adea1787a805ab507702ab244:

• File psl-1983/emode/sleep.sl — part of check-in [eb17ceb7f6] at 2020-04-21 19:40:01 on branch master — Add Reduce 3.0 to the historical section of the archive, and some more
  files relating to version sof PSL from the early 1980s. Thanks are due to
  Paul McJones and Nelson Beebe for these, as well as to all the original
  authors.

  git-svn-id: https://svn.code.sf.net/p/reduce-algebra/code/historical@5328 2bfe0521-f11c-4a00-b80e-6202646ff360 (user: arthurcnorman@users.sourceforge.net, size: 1448) [annotate] [blame] [check-ins using] [more...]

%
% Sleep.SL - Sleep Primitive
% 
% Author:      Alan Snyder
%              Hewlett-Packard/CRC
% Date:        15 July 1982
%
% 
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% 6-Aug-82, WFG:  Modified to include an "inefficient" VAX version.

(CompileTime (load if-system))

(BothTimes
  (progn
    (load common)
    (if_system Dec20
      (load jsys))))

(if_system Dec20
  (de sleep-until-timeout-or-input (n-60ths)     % Dec-20 version

    % Return when either of two conditions are met: (1) Input is available.
    % (2) The specified elapsed time (in units of 1/60th second) has elapsed.
    % Don't waste CPU cycles!

    (for (from i 1 n-60ths 2)
         (until (> (CharsInInputBuffer) 0))
         (do (Jsys0 33 0 0 0 (const jsDISMS)))
         ))
)

(if_system Unix
  (de sleep-until-timeout-or-input (n-60ths)     % Unix version
    % Should use the SELECT system call?
    % Return when either of two conditions are met: (1) Input is available.
    % (2) The specified elapsed time (in units of 1/60th second) has elapsed.
    (let ((timer (time)) % Get "current time" in milliseconds.
           % Approximate number of 1000ths to count (17 roughly equal
           % 16.6666...)
           (n-1000ths (* 17 n-60ths)))
      (for
        % Pause until time runs out,
        (while (< (- (time) timer) n-1000ths))
        % or a character is typed.
        (until (> (CharsInInputBuffer) 0))))))