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regarding malloc and calloc(why should we use both,however b
Joined: 22 Dec 2004
Posts: 1
regarding malloc and calloc(why should we use both,however b
hi all,
please clear this to me.both malloc and calloc are used for memory allocation only.why not we can use any one of these instead of both?
THANKS AND REGARDS
ramakrishna
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Posts: 48
regarding malloc and calloc(why should we use both,however b
Reply embedded...
> From: k ramakrishna [mailto:kvramu1@...]
> Sent: Wednesday, December 22, 2004 8:59 AM
> To: programmers-Town@yahoogroups.com
> Subject: (PT) regarding malloc and calloc(why should we use both,however
> both allocating the memory only)
>
> hi all,
> please clear this to me.both malloc and calloc are used for memory
> allocation only.why not we can use any one of these instead of both?
calloc() does a little more then malloc() - it also initialized the memory
to zero. Sometimes this is not desirable and the result is not portable.
Shyan
Joined: 26 Dec 2004
Posts: 1
regarding malloc and calloc(why should we use both,however b
malloc only allocates memory but calloc intialise the memory to 0s
On Wed, 22 Dec 2004 k ramakrishna wrote :
>hi all,
> please clear this to me.both malloc and calloc are used for memory allocation only.why not we can use any one of these instead of both?
>
>THANKS AND REGARDS
>ramakrishna
>
>Yahoo! India Matrimony: Find your life partneronline.
Joined: 31 Dec 2004
Posts: 5
regarding malloc and calloc(why should we use both,however b
the question still remains that why we need a malloc when calooc will don the same thing by inistialising the memory with zero rther than some random value.Deepika Rani <rani.deepika@...> wrote:
malloc only allocates memory but calloc intialise the memory to 0sOn Wed, 22 Dec 2004 k ramakrishna wrote :>hi all,> please clear this to me.both malloc and calloc are used for memory allocation only.why not we can use any one of these instead of both?>>THANKS AND REGARDS>ramakrishna>>Yahoo! India Matrimony: Find your life partneronline. To unsubscribe : programmers-town-unsubscribe@yahoogroups.com
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Joined: 03 Jan 2005
Posts: 10
regarding malloc and calloc(why should we use both,however b
deo sharma wrote:
> the question still remains that why we need a malloc when calooc will
> don the same thing by inistialising the memory with zero rther than some
> random value.
>
there are circumstances when zeroing out allocated memory is not
required, so malloc is used. and these circumstances are when the
allocated memory will be stuffed wil data as soon as it is allocated. So
there is no need to zero out everything and waste memory cycles
Kapil
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Joined: 27 Dec 2004
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regarding malloc and calloc(why should we use both,however b
Kapil <taxikaps@...> wrote:
deo sharma wrote:> the question still remains that why we need a malloc when calooc will > don the same thing by inistialising the memory with zero rther than some > random value.> there are circumstances when zeroing out allocated memory is not required, so malloc is used. and these circumstances are when the allocated memory will be stuffed wil data as soon as it is allocated. So there is no need to zero out everything and waste memory cycles
Also, note that calloc() is just ALL BITS ZERO. Its *NOT* the same as the "zero initialized" global variables (i.e, a global floating point number or a global pointer getting initialized to "zero" is always correct as per the internal representations (which need not always be all-bits-zero)).
Kapil
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Joined: 29 Dec 2004
Posts: 31
regarding malloc and calloc(why should we use both,however b
From: deo sharma [mailto:deo31@...]
>the question still remains that why we need a malloc when
>calooc will don the same thing by inistialising the memory
>with zero rther than some random value.
Because you want to initialise it to a different value, and having it
initialised twice is pointless?
int i;
void* DefaultValue = (void*)main;
void* pPtrArray = malloc(10*sizeof(*pPtrArray));
for(i=0; i<10; ++i)
pPtrArray[i] = DefaultValue;
What gain does calloc() give you in this instance?
Can you give any good reason why having it filled with `all bits zero`
when this isn`t necessarily the `Null Pointer` (with the associated
extra overhead involved) is any better than gettting randomly filled
memory with no overhead?
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The activity of "debugging", or removing bugs from a program, ends when
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Joined: 25 Jul 2003
Posts: 48
regarding malloc and calloc(why should we use both,however b
Didn`t you get my earlier reply?
> From: deo sharma [mailto:deo31@...]
> Sent: Sunday, December 26, 2004 9:58 PM
> To: Programmers-Town@yahoogroups.com
> Subject: Re: (PT) counter point regarding malloc and calloc(why should
> we use both,however both allocating the memory only)
>
> the question still remains that why we need a malloc when calooc will
> don the same thing by inistialising the memory with zero rther than
> some random value.
Zeroing memory is sometime unnecessary and sometime undesirable.
Unnecessary because you will be setting the data in your code right after
allocation.
Undesirable because they could produce non-portable codes. For example, a
NULL pointer constant is not necessary all-bits set to zero.
HTH
Shyan
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