From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,dd6489250ee6bc95 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII Path: g2news1.google.com!news1.google.com!news.glorb.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local1.nntp.dca.giganews.com!nntp.comcast.com!news.comcast.com.POSTED!not-for-mail NNTP-Posting-Date: Sat, 26 Jun 2004 12:30:49 -0500 Date: Sat, 26 Jun 2004 13:30:49 -0400 From: "Robert I. Eachus" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Poor tasking performance References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Message-ID: <_YCdnTuqM9FUL0DdRVn-iQ@comcast.com> NNTP-Posting-Host: 24.147.90.114 X-Trace: sv3-iJQzNQWfjA+PFNyZSEwK2HKO9wydiariPV73/q+x3J5GWdJUig7eRDzcer0XiXem0Nxw1acaPQzcLnW!VyODLI19MSl3/wZwZpUwm6Ajth2w2/6M1152j5i2Ys6UNlWRQH4uMBZzgMoxYw== X-Complaints-To: abuse@comcast.net X-DMCA-Complaints-To: dmca@comcast.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Xref: g2news1.google.com comp.lang.ada:1932 Date: 2004-06-26T13:30:49-04:00 List-Id: Bj�rn Persson wrote: > When I press a key, in most cases either a character shows up on the > screen or some action is triggered. I suppose modifier keys (Shift, > Ctrl, ...) and "dead" accents could be buffered. Right now I can only > come up with one case when letters don't have to be read immediately: > when the user is typing a password and characters are neither echoed nor > indicated with asterisks. Ah, but look at it this way--which is what the computer actually does. The effect of generating a new screen image to be displayed has to be done once per screen refresh, which is typically today in the range of 60 to 100 times per second. There is no need for an additional interrupt to read the keyboard in between screen refreshes most of the time. Of course, the Get_Immediate call in Ada should support exactly that. Why? Lots of random number seed generators use the number of microseconds between keypresses to generate secret keys. If the times measured are multiples of the screen refresh clock, your secret key may not be all that secret. (Most algorithms do detect how much entropy they are getting per keypress, so the real cost is that you have to type for a lot longer.) -- Robert I. Eachus "Reason and experience both forbid us to expect that national morality can prevail in exclusion of religious principles." -- George Washington