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Re: Installing gForth on the Raspberry Pi

From rickman <gnuarm@gmail.com>
Newsgroups comp.lang.forth, comp.sys.raspberry-pi
Subject Re: Installing gForth on the Raspberry Pi
Date 2014-10-27 18:23 -0400
Organization A noiseless patient Spider
Message-ID <m2mgmc$1ho$1@dont-email.me> (permalink)
References <m2j5vj$rem$1@dont-email.me> <m2jnvm$ji$1@dont-email.me> <m2jr6j$cfs$1@dont-email.me> <m2k3hn$5lv$1@dont-email.me> <544e13b6$0$6883$e4fe514c@dreader36.news.xs4all.nl>

Cross-posted to 2 groups.

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On 10/27/2014 5:43 AM, Albert van der Horst wrote:
> In article <m2k3hn$5lv$1@dont-email.me>, rickman  <gnuarm@gmail.com> wrote:
>>
>> The windows I/O is just read-file, but it returns a length which can be
>> zero.  Comkey? asks for 1 byte so the char is saved and the routine
>> returns if it was found or not.  When Comkey is called it calls Comkey?
>> to make sure a char is in the buffer than returns the char from the
>> buffer.  Sounds like I can do the same thing.  I just need to find the
>> file I/O calls.  But the serial port needs to be set up.  One reference
>> said to do that outside of the app.
>
> (I've some recent experience, trying to write a terminal server
> for single board computers like the MPS430).

What is a terminal *server*?


> You didn't notice but returning with a count of zero is not smart
> but stupid.
> Suppose you have a 300 baud line and a 4 Ghz machine. Then you're effectively
> polling and hanging up the machine. It is stupid not to wait at least
> the time that is needed for a single character to arrive, 30 mS.
> So we have to play with time outs of the order of one character
> timing, which is milliseconds. Writing a serial line is full of those
> real time issues.
> Windows nt followed to an extent the VMS philosophy which is
> 1. set out a read, return immediately
> 2. If the read finishes *as configured* (this means x characters,
> or a time out, or a ^D, or a ^J or and ASCII null, or a combination
> of those) it sets and event flag.
> 3. You can have your program wait, on any combination of event flags,
> so you can keep track of several simultaneous read and write operations.
>
> This is generally considered superior to the Unix approach with the
> select mechanism, but ...
> (In the 80's I heard, Unix is good for development, VMS is good for
> real time. )
> MSDOS documentation, implementation and integration with the rest
> of the OS is lacking in many respects. (Did I say MSDOS, I mean MS windows.)
>
> There are no hard specifications, now how is one supposed to write a
> driver for USB serial with those specs?
>
> This also answers the question, why threads in Linux?
> You really need them for time outs alone.

I can't say I follow your reasoning.  I don't see how bit rate has 
anything to do with the issue.  If a read is requested and there is no 
data in the read buffer, the routine returns indicating it read no data. 
  If there is data in the buffer it returns the data and the lesser 
count of data in the buffer and the amount requested.  Actually, this is 
the same as the no data case where it returns the data in the buffer 
which is none and returns the size which is zero.  In all cases it 
returns immediately.  If the program wishes to wait for data it just 
sits in a loop checking for new data and hopefully wasting time by 
calling a wait routine rather than tying up CPU with a spin loop.

Where exactly is the problem?

-- 

Rick

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Thread

Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 12:02 -0400
  Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-26 16:11 +0000
    Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 12:20 -0400
      Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 12:44 -0400
        Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-26 17:09 +0000
          Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 14:45 -0400
            Re: Installing gForth on the Raspberry Pi andrew@cucumber.demon.co.uk (Andrew Gabriel) - 2014-10-26 18:57 +0000
              Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 15:14 -0400
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-26 19:47 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 16:10 -0400
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 08:43 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 17:31 -0400
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-28 14:18 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 17:15 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 13:24 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 16:48 -0400
                Re: Installing gForth on the Raspberry Pi Raymond Wiker <rwiker@gmail.com> - 2014-10-26 22:12 +0100
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 17:20 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 14:39 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 17:46 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 15:11 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 18:25 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 15:58 -0700
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 09:20 +0000
                Re: Installing gForth on the Raspberry Pi josv@planet.nl - 2014-10-29 07:02 -0700
                Re: Installing gForth on the Raspberry Pi Coos Haak <chforth@hccnet.nl> - 2014-10-30 11:20 +0100
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 08:56 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-27 10:14 +0000
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 08:48 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 17:35 -0400
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-28 14:24 +0000
                Re: Installing gForth on the Raspberry Pi Alan Adams <alan@adamshome.org.uk> - 2014-10-28 15:52 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 12:49 -0400
                Re: Installing gForth on the Raspberry Pi Ray <ray@invalid.com> - 2014-10-28 17:22 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 17:02 -0400
                Re: Installing gForth on the Raspberry Pi Lars Brinkhoff <lars.spam@nocrew.org> - 2014-10-27 10:07 +0100
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 09:22 +0000
                Re: Installing gForth on the Raspberry Pi stephenXXX@mpeforth.com (Stephen Pelc) - 2014-10-27 11:30 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 17:37 -0400
                Re: Installing gForth on the Raspberry Pi stephenXXX@mpeforth.com (Stephen Pelc) - 2014-10-28 12:41 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 12:51 -0400
                Re: Installing gForth on the Raspberry Pi stephenXXX@mpeforth.com (Stephen Pelc) - 2014-10-28 18:44 +0000
                Re: Installing gForth on the Raspberry Pi anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-10-27 11:49 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 17:51 -0400
                Re: Installing gForth on the Raspberry Pi "Elizabeth D. Rather" <erather@forth.com> - 2014-10-27 20:31 -1000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 03:01 -0400
                Re: Installing gForth on the Raspberry Pi "Elizabeth D. Rather" <erather@forth.com> - 2014-10-27 21:14 -1000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 03:45 -0400
                Re: Installing gForth on the Raspberry Pi "Elizabeth D. Rather" <erather@forth.com> - 2014-10-27 22:14 -1000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 14:09 -0400
                Re: Installing gForth on the Raspberry Pi Mel Wilson <mwilson@the-wire.com> - 2014-10-28 21:50 +0000
                Re: Installing gForth on the Raspberry Pi "Ivan D. Reid" <Ivan.Reid@ivan.fsnet.co.uk> - 2014-10-29 00:01 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 20:50 -0400
                Re: Installing gForth on the Raspberry Pi "Ivan D. Reid" <Ivan.Reid@ivan.fsnet.co.uk> - 2014-10-29 01:20 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-10-29 00:58 +0000
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-28 18:04 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-29 01:40 -0400
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-10-29 12:41 +0000
                Re: Installing gForth on the Raspberry Pi Theo Markettos <theom+news@chiark.greenend.org.uk> - 2014-11-16 15:34 +0000
                Re: Installing gForth on the Raspberry Pi "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-11-16 12:01 -0500
                Re: Installing gForth on the Raspberry Pi The Natural Philosopher <tnp@invalid.invalid> - 2014-11-16 17:22 +0000
                Re: Installing gForth on the Raspberry Pi Rob Morley <nospam@ntlworld.com> - 2014-11-16 17:06 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-16 18:27 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-11-16 19:19 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-16 20:11 +0000
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-11-17 11:56 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-17 13:42 +0000
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-11-17 10:14 -0800
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-11-16 17:25 +0000
                Re: Installing gForth on the Raspberry Pi Rob Morley <nospam@ntlworld.com> - 2014-11-16 17:40 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-11-16 19:12 +0000
                Re: Installing gForth on the Raspberry Pi Alan Adams <alan@adamshome.org.uk> - 2014-11-16 19:50 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-11-16 21:22 +0000
                Re: Installing gForth on the Raspberry Pi Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2014-11-16 17:38 -0500
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-17 00:12 +0000
                Re: Installing gForth on the Raspberry Pi Michael J. Mahon <mjmahon@aol.com> - 2014-11-16 19:53 -0600
                Re: Installing gForth on the Raspberry Pi Coos Haak <chforth@hccnet.nl> - 2014-11-17 01:00 +0100
                Re: Installing gForth on the Raspberry Pi Alan Adams <alan@adamshome.org.uk> - 2014-11-17 12:03 +0000
                Re: Installing gForth on the Raspberry Pi druck <news@druck.org.uk> - 2014-11-18 20:03 +0000
                Re: Installing gForth on the Raspberry Pi druck <news@druck.org.uk> - 2014-11-16 18:20 +0000
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-29 11:53 +0000
                Re: Installing gForth on the Raspberry Pi humptydumpty <ouatubi@gmail.com> - 2014-10-27 06:52 -0700
            Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 12:02 -0700
              Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 15:18 -0400
            Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-26 20:24 +0000
              Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 17:09 -0400
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-26 22:05 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 20:27 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 17:45 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 21:09 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 18:22 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 23:20 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-26 20:53 -0700
                Re: Installing gForth on the Raspberry Pi andrew@cucumber.demon.co.uk (Andrew Gabriel) - 2014-10-27 10:23 +0000
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-27 13:36 -0700
                Re: Installing gForth on the Raspberry Pi andrew@cucumber.demon.co.uk (Andrew Gabriel) - 2014-10-27 22:23 +0000
                Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-27 09:43 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-27 10:26 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-10-27 13:15 +0000
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-27 14:12 +0000
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-10-27 15:34 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 18:31 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-27 15:50 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 19:26 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-27 16:37 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 20:17 -0400
                Re: Installing gForth on the Raspberry Pi Paul Rubin <no.email@nospam.invalid> - 2014-10-27 17:24 -0700
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 03:10 -0400
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-28 08:11 +0000
                Re: Installing gForth on the Raspberry Pi Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2014-10-28 09:13 -0400
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-28 08:11 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 04:14 -0400
                Re: Installing gForth on the Raspberry Pi Gordon Henderson <gordon+usenet@drogon.net> - 2014-10-28 08:15 +0000
                Re: Installing gForth on the Raspberry Pi "A. Dumas" <alexandre@dumas.fr.invalid> - 2014-10-28 10:22 +0100
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 15:53 -0400
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 17:10 -0400
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-27 18:23 -0400
                Re: Installing gForth on the Raspberry Pi Nomen Nescio <nobody@dizum.com> - 2014-11-15 23:09 +0100
                Re: Installing gForth on the Raspberry Pi Martin Gregorie <martin@address-in-sig.invalid> - 2014-11-16 00:35 +0000
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-11-16 00:06 -0500
        Re: Installing gForth on the Raspberry Pi albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-26 19:36 +0000
          Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-26 16:24 -0400
        Re: Installing gForth on the Raspberry Pi Hannu Vuolasaho <vuokkosetae@gmail.com> - 2014-10-27 23:48 +0200
        Re: Installing gForth on the Raspberry Pi josv@planet.nl - 2014-10-28 05:27 -0700
          Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 16:02 -0400
            Re: Installing gForth on the Raspberry Pi Coos Haak <chforth@hccnet.nl> - 2014-10-28 22:57 +0100
              Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 19:54 -0400
                Re: Installing gForth on the Raspberry Pi rickman <gnuarm@gmail.com> - 2014-10-28 20:01 -0400
    Re: Installing gForth on the Raspberry Pi "A. Dumas" <alexandre@dumas.fr.invalid> - 2014-10-27 04:10 +0100
  QUESTIONS and ANSWERS pass in the dark  ;< - was [ Re: Installing gForth on the Raspberry Pi ] Richard Owlett <rowlett@cloud85.net> - 2014-10-28 14:06 -0500

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