Re: Updating C default type

From	glen herrmannsfeldt <gah@ugcs.caltech.edu>
Newsgroups	comp.lang.c
Subject	Re: Updating C default type
Date	2014-04-24 20:17 +0000
Organization	Aioe.org NNTP Server
Message-ID	<ljbrgm$bkr$1@speranza.aioe.org> (permalink)
References	<lj66ho$8fg$1@speranza.aioe.org> <lj6750$a10$2@speranza.aioe.org> <lj6802$cek$1@speranza.aioe.org> <ljbdub$k4p$1@dont-email.me>

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Ken Brody <kenbrody@spamcop.net> wrote:

(snip on floating point arguments to malloc(), among others)

> So malloc() should be passed an *approximate* number of bytes to allocate?

>> With a double arg, malloc could allocate upto 1.7e308 bytes. It will be
>> many years, before RAM density increases to exceed this size. Whereas, int
>> can only allocate upto 2e9 bytes.

> First, I wasn't aware that ints were limited to 32 bits.

> Second, malloc() takes size_t, not int.

> Finally, since the value passed to malloc() must, logically, be able to be 
> express in no more bits than the number of bits in an address, why do you 
> feel it is important to be able to pass values larger than the address 
> space, and to do so using approximate rather than exact values?

The OP should get a Burroughs B5500, though he might also have to
write the C compiler for it.

The floating point format of the B5500 is designed such that it
can also be the fixed point (integer) format.

The significand has the binary point on the right, such that it is
an integer. The exponent is not biased, such that an exponent of
zero has all bits zero. The normalization prefers a zero exponent 
if no significant bits are lost. It is word addressed with 48 bit
words, allowing for either 48 bits in floating point or 40 bits
for integers.

The normal text form is eight 6 bit characters per word, which would
not work for C's char, though.

-- glen

Thread

Updating C default type Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2014-04-22 16:48 +0000
  Re: Updating C default type jacob navia <jacob@spamsink.net> - 2014-04-22 18:59 +0200
    Re: Updating C default type Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2014-04-22 17:13 +0000
      Re: Updating C default type Keith Thompson <kst-u@mib.org> - 2014-04-22 11:59 -0700
      Re: Updating C default type Kaz Kylheku <kaz@kylheku.com> - 2014-04-22 19:12 +0000
        Re: Updating C default type jacob navia <jacob@spamsink.net> - 2014-04-25 19:31 +0200
      Re: Updating C default type Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 15:41 -0500
      Re: Updating C default type "BartC" <bc@freeuk.com> - 2014-04-22 21:47 +0100
      Re: Updating C default type Ken Brody <kenbrody@spamcop.net> - 2014-04-24 12:25 -0400
        Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-24 10:32 -0700
        Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 20:17 +0000
        Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 21:03 +0000
    Re: Updating C default type Gareth Owen <gwowen@gmail.com> - 2014-04-22 19:12 +0100
  Re: Updating C default type Keith Thompson <kst-u@mib.org> - 2014-04-22 10:26 -0700
  Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 10:28 -0700
  Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-22 18:20 +0000
    Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-22 19:09 +0000
      Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-04-22 15:35 -0400
        Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-04-22 15:38 -0400
        Re: Updating C default type Kaz Kylheku <kaz@kylheku.com> - 2014-04-22 19:54 +0000
          Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-22 21:27 +0000
            Re: Updating C default type "BartC" <bc@freeuk.com> - 2014-04-22 23:08 +0100
    Re: Updating C default type Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-22 22:03 +0100
    Re: Updating C default type Thomas Jahns <jahns@idontlikespam.dkrz.de> - 2014-04-23 09:59 +0200
    Re: Updating C default type David Thompson <dave.thompson2@verizon.net> - 2014-05-25 16:44 -0400
      Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-05-26 05:48 +0000
  Re: Updating C default type "Osmium" <r124c4u102@comcast.net> - 2014-04-22 14:01 -0500
    Re: Updating C default type Quentin Pope <qp19433@hotmail.NOSPAM.com> - 2014-04-23 16:57 +0000
      Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-04-23 13:13 -0400
      Re: Updating C default type Kaz Kylheku <kaz@kylheku.com> - 2014-04-23 18:02 +0000
      Re: Updating C default type Keith Thompson <kst-u@mib.org> - 2014-04-23 11:33 -0700
  Re: Updating C default type Kaz Kylheku <kaz@kylheku.com> - 2014-04-22 19:08 +0000
    Re: Updating C default type Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-22 22:08 +0100
      Re: Updating C default type "BartC" <bc@freeuk.com> - 2014-04-22 22:19 +0100
    Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-22 14:13 -0700
      Re: Updating C default type Stephen Sprunk <stephen@sprunk.org> - 2014-04-23 11:55 -0500
        Re: Updating C default type Keith Thompson <kst-u@mib.org> - 2014-04-23 10:55 -0700
          Re: Updating C default type Robert Wessel <robertwessel2@yahoo.com> - 2014-04-24 00:03 -0500
        Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-23 22:37 -0700
          Re: Updating C default type glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-24 12:05 +0000
      Re: Updating C default type gordonb.ez7sl@burditt.org (Gordon Burditt) - 2014-04-25 06:11 -0500
        Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-04-25 08:48 -0400
  Re: Updating C default type Stephen Sprunk <stephen@sprunk.org> - 2014-04-22 15:30 -0500
    Re: Updating C default type ralph <nt_consulting@yahoo.com> - 2014-04-22 23:18 -0500
  Re: Updating C default type Ken Brody <kenbrody@spamcop.net> - 2014-04-24 12:28 -0400
  Re: Updating C default type gordonb.oztxz@burditt.org (Gordon Burditt) - 2014-04-24 23:50 -0500
    Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-04-25 08:41 -0400
  Re: Updating C default type Hans Vlems <hvlems@freenet.de> - 2014-05-25 23:57 -0700
    Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-05-26 01:55 -0700
    Re: Updating C default type Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-05-26 13:01 +0100
      Re: Updating C default type Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-05-26 13:12 -0700
        Re: Updating C default type Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-05-26 22:31 +0100
          Re: Updating C default type Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-05-26 23:55 +0100
          Re: Updating C default type Keith Thompson <kst-u@mib.org> - 2014-05-26 17:11 -0700
    Re: Updating C default type James Kuyper <jameskuyper@verizon.net> - 2014-05-27 07:54 -0400

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