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Re: unsigned int

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David Brown <david.brown@hesbynett.no> writes:
[...]
> Personally, I would rather have have a selection of byte-sized types in
> a language like C.  I would like a type "char" which can hold character
> data such as 'a'.  But assigning an integer value to a char (without
> appropriate casts) should be an error.  I would like a type "byte" which
> represents raw data in memory - "byte *" would be used instead of "void
> *" in C, and also in many cases where "char *" is used.  So functions
> like "memcpy" would deal in "byte*" pointers, "malloc" would return a
> "byte*", but "strcpy" would use "char*" pointers.  And I would like
> numerical types of byte size.  To fit C practice, these might be "signed
> short short int" and "unsigned short short int" (with "signed" being the
> default), though I am sure some people would object to those names.

Apart from the implicit conversion of numeric type to char, that's
pretty much what we have.  `char` is the type for (narrow) characters,
`unsigned char` represents raw data, and `signed char` is a narrow
signed integer type.

> But we have what we have in C - it's not going to change.  The best we
> can do is write code in a way that minimises the risk of errors - and
> that includes being explicit about using signed or unsigned char when
> using them for numbers.

Agreed.

As for uint8_t and int8_t, you should use those only if you need
*exactly* 8 bits.  If you just want a narrow integer type of *at least*
8 bits, you can use unsigned char and signed char -- or
[u]int_(least|fast)8_t, depending on your requirements.

[...]

> One should, of course, rely on CHAR_BIT == 8 without ensuring a clear
> compile-time failure if that is not the case.  That might be done by
> testing CHAR_BIT and issuing a #error directive - but IMHO it is good
> enough to simply make use of uint8_t and int8_t types.

I presume you omitted a "not" there.

On the other hand, it's reasonable to assume CHAR_BIT == 8 if your code
already relies on POSIX features.  (The same probably applies to the
Windows API.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Re: unsigned int "Osmium" <r124c4u102@comcast.net> - 2016-07-31 12:40 -0500
  Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 11:01 +0200
    Re: unsigned int James Kuyper <jameskuyper@verizon.net> - 2016-08-01 10:15 -0400
    Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 09:59 -0500
      Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 17:21 +0200
        Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-01 09:55 -0700
          Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 22:42 +0200
            Re: unsigned int supercat@casperkitty.com - 2016-08-01 14:18 -0700
        Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 13:11 -0500
          Re: unsigned int Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-01 19:46 +0100
            Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-01 18:20 -0500
              Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-02 10:18 +0200
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 09:35 -0500
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-02 08:00 -0700
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 11:12 -0500
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-02 17:11 +0200
                Re: unsigned int Les Cargill <lcargill99@comcast.com> - 2016-08-02 11:55 -0500
                Re: unsigned int supercat@casperkitty.com - 2016-08-02 10:16 -0700
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 14:02 +0200
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-03 08:58 -0700
                Re: unsigned int James Kuyper <jameskuyper@verizon.net> - 2016-08-02 13:57 -0400
                Re: unsigned int Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-02 19:30 +0100
                Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-02 11:38 -0700
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 14:12 +0200
                Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-03 13:45 +0200
          Re: unsigned int Keith Thompson <kst-u@mib.org> - 2016-08-01 12:02 -0700
            Re: unsigned int David Brown <david.brown@hesbynett.no> - 2016-08-01 23:01 +0200

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