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Groups > comp.lang.c > #102321
| From | Ben Bacarisse <ben.usenet@bsb.me.uk> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Access structure members via pointer to an array of structures |
| Date | 2017-01-22 13:31 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <878tq3xluk.fsf@bsb.me.uk> (permalink) |
| References | (1 earlier) <f59a2493-8589-4c7e-be51-4749d92f8c04@googlegroups.com> <lntw8sf1hy.fsf@kst-u.example.com> <87pojf5wk4.fsf@gmail.com> <87pojfxs1h.fsf@bsb.me.uk> <o625rd$q8n$1@dont-email.me> |
BartC <bc@freeuk.com> writes:
> On 22/01/2017 11:17, Ben Bacarisse wrote:
>> Gareth Owen <gwowen@gmail.com> writes:
>>
>>> Keith Thompson <kst-u@mib.org> writes:
>>>
>>>> Why would you tell someone trying to learn C about "array pointer
>>>> equivalence"? Arrays and pointers are not equivalent.
>>>
>>> They are occasionally
>>
>> "array pointer equivalence" does not suggest something occasional!
>>
>> There are a number of people here determined to avoid any explanation
>> that simplified the issue. Just refer to the "array to pointer
>> conversion" and you are much closer to the truth without implying any
>> false equivalence.
>>
>>> f(char *ptr){
>>> printf("%s - %u\n",ptr,(unsigned)sizeof(ptr));
>>> }
>>>
>>> f(char arr[10]){
>>> printf("%s - %u\n",arr,(unsigned)sizeof(arr));
>>> }
>>
>> There are no arrays in this code and I don't think Malcolm was talking
>> about the interchangeability of * and [] syntax in a parameter list.
>
> Maybe he was talking about the equivalence of 'years' and '*dat_years'
I think he knows C better than that!
> here when used in most expression contexts:
>
> data years[DATA_SIZE]; // [an array]
> data *dat_years = years; // [a pointer]
He was clearly taking about the fact that years converts to a pointer in
most contexts. When talking to people learning C, that's better than
suggesting an equivalence that does not exist.
<snip>
--
Ben.
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Access structure members via pointer to an array of structures Alla _ <modelling.data@gmail.com> - 2017-01-21 02:00 -0800
Re: Access structure members via pointer to an array of structures Alla _ <modelling.data@gmail.com> - 2017-01-21 02:08 -0800
Re: Access structure members via pointer to an array of structures Chad <cdalten@gmail.com> - 2017-01-21 07:36 -0800
Re: Access structure members via pointer to an array of structures Jerry Stuckle <jstucklex@attglobal.net> - 2017-01-21 11:13 -0500
Re: Access structure members via pointer to an array of structures Jerry Stuckle <jstucklex@attglobal.net> - 2017-01-21 11:08 -0500
Re: Access structure members via pointer to an array of structures Chad <cdalten@gmail.com> - 2017-01-21 09:09 -0800
Re: Access structure members via pointer to an array of structures Jerry Stuckle <jstucklex@attglobal.net> - 2017-01-21 14:32 -0500
Re: Access structure members via pointer to an array of structures Chad <cdalten@gmail.com> - 2017-01-21 12:57 -0800
Re: Access structure members via pointer to an array of structures Chad <cdalten@gmail.com> - 2017-01-21 13:04 -0800
Re: Access structure members via pointer to an array of structures Jerry Stuckle <jstucklex@attglobal.net> - 2017-01-21 17:59 -0500
Re: Access structure members via pointer to an array of structures cross@spitfire.i.gajendra.net (Dan Cross) - 2017-01-22 14:02 +0000
Re: Access structure members via pointer to an array of structures raltbos@xs4all.nl (Richard Bos) - 2017-01-22 14:17 +0000
Re: Access structure members via pointer to an array of structures Tim Rentsch <txr@alumni.caltech.edu> - 2017-01-30 05:25 -0800
Re: Access structure members via pointer to an array of structures Jerry Stuckle <jstucklex@attglobal.net> - 2017-01-21 17:57 -0500
Re: Access structure members via pointer to an array of structures Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-21 08:09 -0800
Re: Access structure members via pointer to an array of structures Keith Thompson <kst-u@mib.org> - 2017-01-21 15:15 -0800
Re: Access structure members via pointer to an array of structures Gareth Owen <gwowen@gmail.com> - 2017-01-22 08:27 +0000
Re: Access structure members via pointer to an array of structures Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 11:17 +0000
Re: Access structure members via pointer to an array of structures BartC <bc@freeuk.com> - 2017-01-22 11:44 +0000
Re: Access structure members via pointer to an array of structures Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-01-22 04:27 -0800
Re: Access structure members via pointer to an array of structures Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 13:32 +0000
Re: Access structure members via pointer to an array of structures Keith Thompson <kst-u@mib.org> - 2017-01-22 07:54 -0800
Re: Access structure members via pointer to an array of structures Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 13:31 +0000
Re: Access structure members via pointer to an array of structures Gareth Owen <gwowen@gmail.com> - 2017-01-22 14:02 +0000
Re: Access structure members via pointer to an array of structures Keith Thompson <kst-u@mib.org> - 2017-01-22 07:50 -0800
Re: Access structure members via pointer to an array of structures Manfred <noname@invalid.add> - 2017-01-21 17:15 +0100
Re: Access structure members via pointer to an array of structures David Brown <david.brown@hesbynett.no> - 2017-01-21 17:59 +0100
Re: Access structure members via pointer to an array of structures Alla _ <modelling.data@gmail.com> - 2017-01-21 09:09 -0800
Re: Access structure members via pointer to an array of structures Barry Schwarz <schwarzb@dqel.com> - 2017-01-21 09:27 -0800
Re: Access structure members via pointer to an array of structures Alla _ <modelling.data@gmail.com> - 2017-01-21 09:30 -0800
Re: Access structure members via pointer to an array of structures Alla _ <modelling.data@gmail.com> - 2017-01-21 09:25 -0800
Re: Access structure members via pointer to an array of structures "Peter \"Shaggy\" Haywood" <phaywood@alphalink.com.au> - 2017-01-30 22:04 +1100
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