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Date:      Sun, 20 Feb 2005 16:24:54 +0000
From:      Chris Hodgins <chodgins@cis.strath.ac.uk>
To:        Gert Cuykens <gert.cuykens@gmail.com>
Cc:        freebsd-questions@freebsd.org
Subject:   Re: c++
Message-ID:  <4218B9D6.8060100@cis.strath.ac.uk>
In-Reply-To: <ef60af0905022007341719022b@mail.gmail.com>
References:  <ef60af09050219015116024f83@mail.gmail.com> <5b8472dd5925a0b0b59f15cd9f8e15f3@shire.net> <ef60af0905021915074e5d2929@mail.gmail.com> <675354920.20050220001731@wanadoo.fr> <ef60af0905021923411a0272b6@mail.gmail.com> <20050220124749.GA523@tuatara.fishballoon.org> <ef60af0905022007341719022b@mail.gmail.com>

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Gert Cuykens wrote:
> On Sun, 20 Feb 2005 12:47:50 +0000, Scott Mitchell
> <scott+lists.freebsd@fishballoon.org> wrote:
> 
>>On Sun, Feb 20, 2005 at 08:41:30AM +0100, Gert Cuykens wrote:
>>
>>>So if data is declared as a gchar *data; for example, then the value
>>>of data is a memory adress right ? So if A=data; and B=&data; then A
>>>and B are exactly the same result right ?
>>
>>No.  A is a 'pointer to gchar' (or gchar*) and B is a 'pointer to pointer
>>to gchar' (or gchar**).  The '&data' syntax means 'the address of the data
>>variable', ie. the address of a gchar*, whereas data itself contains the
>>address of a gchar.
>>
>>
>>>Now why would anybody want a gchar when a integer is needed ? That is
>>>just making it more complicated then it already is?
>>
>>Because the code in question deals with gchars (whatever they are) not
>>integers?  They won't necessarily be the same thing on different
>>architectures, or even different compilers on the same architecture.  Also,
>>the type is called 'gchar' presumably because it logically holds some kind
>>of character data, whereas an integer variable holds an integer.  Calling
>>them different things in the code helps to make it clear what the
>>programmer's intention is, even if the two types happen to have the same
>>representation on a given machine/compiler.
>>
>>In any case, this stuff really has nothing to do with FreeBSD - you should
>>be asking these questions in a C/C++ programming group.
>>
>>Cheers,
>>
>>        Scott
>>
>>--
> 
> 
> Thx i think i understand now :)
> 
> PS Freebsd source is c++ right ? So you could also call this the free
> c++ question mailing list :)

No.  FreeBSD is written in C.  This is surely a mailing list for people 
who want to ask and answer questions about the FreeBSD Operating System.

> 
> Also about all the get a c++ book comments, i tryed that once but when
> i ask the book a question, it doesnt say anything back. It only makes
> noises when you flaper the pages trough the wind.
> 
> By the way if somebody passing your street asking for direction you
> dont answer get a map either right ?
> 

This is more like somebody passing your street asking for directions to 
a street in another country.

Both comp.lang.c and comp.lang.c++ are both pretty intolerant to people 
asking basic questions which are heavily documented in the FAQs for the 
newsgroups.  They generally expect you to have at least tried to 
understand what you are doing before asking a question.  If you had 
tried to understand your problem and looked at the faqs you would have 
found an amazing amount of information on what you are after.  Before 
you do anything else you should now go read 
http://www.eskimo.com/~scs/C-faq/top.html and educate yourself a bit 
more about C.

People are not trying to be unhelpful when the tell you to RTFM or read 
a book.  They are trying to point out areas of knowledge that you can 
reference to gain more insight into your problem.  Noone is just going 
to do your homework for you.

Good luck learning about C.
Chris



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