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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Why is glibc not extensive?
Date: Sat, 26 Nov 2022 09:07:58 -0800
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Michael S <already5chosen@yahoo.com> writes:

> On Friday, November 18, 2022 at 2:47:42 PM UTC+2, A wrote:
>
>> On Friday, 18 November 2022 at 17:39:58 UTC+5:30, David Brown wrote:

[...]

>>> a) Use size_t like the rest of the world.
>>
>> This is a problem.  If I am not convinced then why should I follow
>> the world?  The world can use size_t but I will use long and if the
>> world says that I should be using size_t then I will ignore that.
>
> So, you don't want to use size_t because it is unsigned.  Well.
> Then use signed type ptrdiff_t.  When you want to hold size of
> arbitrary objects ptrdiff_t is more portable than 'long'.
> In corner case of size of object that occupies more than half
> of address space both ptrdiff_t and 'long' are not good enough,
> but at least ptrdiff_t works in all other cases.  The same can't
> be said about 'long' which does not work in pretty common case
> of size of big objects (>= 2GB) on Win64.

IMO it's a mistake to hard-wire either 'long' or 'ptrdiff_t' to
be the name of a (signed) size type.  Whatever type is chosen
should allow as wide a range of values as needed, and neither of
those types will necessarily do that.  Furthermore the type name
used should reflect the purpose rather than the representation.
Assuming the name 's_size' is considered appropriate and
acceptable, a suitable typedef can be chosen using a scheme
along these lines:

    #include <limits.h>
    #include <stdint.h>

    #if INT_MAX >= SIZE_MAX
    typedef int             s_size;
    #elif LONG_MAX >= SIZE_MAX
    typedef long            s_size;
    #elif defined LLONG_MAX && LLONG_MAX >= SIZE_MAX
    typedef long long       s_size;
    #else
    typedef intmax_t        s_size;
    #endif

after which any interfaces desired should use 's_size' for values
of a signed size type.