Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int) memory
delete []pBuf // this will delete all the memory allocated to pBuf
Question: How come the application knows that it has to delete memory of
pBuf for 10 * sizeof(int) from the statement "delete []pBuf "?
Pls. reply back
John
6  1732 
On 2007-12-24 00:57:39 -0500, "AS" <as**********@r ediffmail.comsa id:
Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int) memory
delete []pBuf // this will delete all the memory allocated to pBuf
Question: How come the application knows that it has to delete memory of
pBuf for 10 * sizeof(int) from the statement "delete []pBuf "?
Pls. reply back
John
Same way how free() knows how much memory to reclaim from malloc(): It
keeps internal data structure on what pieces of memory were issued.
--
-kira
Thanx for the reply. I guessed the same. Can you explain in detail or any
sample code to demonstrate this ?
"Kira Yamato" <ki*****@earthl ink.netwrote in message
news:2007122400 425016807-kirakun@earthli nknet...
On 2007-12-24 00:57:39 -0500, "AS" <as**********@r ediffmail.comsa id:
>Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int) memory
delete []pBuf // this will delete all the memory allocated to pBuf
Question: How come the application knows that it has to delete memory of
pBuf for 10 * sizeof(int) from the statement "delete []pBuf "?
Pls. reply back
John
Same way how free() knows how much memory to reclaim from malloc(): It
keeps internal data structure on what pieces of memory were issued.
--
-kira
"Kira Yamato" <ki*****@earthl ink.netwrote in message
news:2007122400 425016807-kirakun@earthli nknet...
>On 2007-12-24 00:57:39 -0500, "AS" <as**********@r ediffmail.com>
said:
>>Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int)
memory delete []pBuf // this will delete all the memory allocated to
pBuf Question: How come the application knows that it has to delete
memory of pBuf for 10 * sizeof(int) from the statement "delete
[]pBuf "?
>Same way how free() knows how much memory to reclaim from malloc(): It
keeps internal data structure on what pieces of memory were
issued.
Thanx for the reply. I guessed the same. Can you explain in detail or
any sample code to demonstrate this ?
It's the compiler/OS that keeps track. It may be done differently in
different compilers and OSes. I think you gave the perfect example, what
more would you need?
--
Jim Langston ta*******@rocke tmail.com
I would like to know how this is happening internally, suppose that if we
have to write our own Memory Manager which handle these ?
"Jim Langston" <ta*******@rock etmail.comwrote in message
news:Ne******** *****@newsfe05. lga...
>"Kira Yamato" <ki*****@earthl ink.netwrote in message
news:200712240 0425016807-kirakun@earthli nknet...
>>On 2007-12-24 00:57:39 -0500, "AS" <as**********@r ediffmail.com>
said:
Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int)
memory delete []pBuf // this will delete all the memory allocated
to
pBuf Question: How come the application knows that it has to delete
memory of pBuf for 10 * sizeof(int) from the statement "delete
[]pBuf "?
>>Same way how free() knows how much memory to reclaim from malloc(): It
keeps internal data structure on what pieces of memory were
issued.
>Thanx for the reply. I guessed the same. Can you explain in detail or
any sample code to demonstrate this ?
It's the compiler/OS that keeps track. It may be done differently in
different compilers and OSes. I think you gave the perfect example, what
more would you need?
--
Jim Langston
ta*******@rocke tmail.com
AS wrote:
Please don't top-post.
"Jim Langston" <ta*******@rock etmail.comwrote in message
news:Ne******** *****@newsfe05. lga...
>>"Kira Yamato" <ki*****@earthl ink.netwrote in message
news:20071224 00425016807-kirakun@earthli nknet...
On 2007-12-24 00:57:39 -0500, "AS" <as**********@r ediffmail.com>
said:
Hello,
consider the following statements,
int *pBuf = new int[10]; //this will allocate 10*sizeof(int)
memory delete []pBuf // this will delete all the memory allocated
to
pBuf Question: How come the application knows that it has to delete
memory of pBuf for 10 * sizeof(int) from the statement "delete
[]pBuf "?
Same way how free() knows how much memory to reclaim from malloc(): It
keeps internal data structure on what pieces of memory were
issued.
Thanx for the reply. I guessed the same. Can you explain in detail or
any sample code to demonstrate this ?
It's the compiler/OS that keeps track. It may be done differently in
different compilers and OSes. I think you gave the perfect example, what
more would you need?
Or quote signatures.
>>
I would like to know how this is happening internally, suppose that if we
have to write our own Memory Manager which handle these ?
The answer is part of your operating system or runtime libraries. If
you can , consult the source for those. Writing your own memory manager
is an excellent way to understand the problems involved with dynamic
memory management.
--
Ian Collins.
On Dec 24, 12:43*pm, "AS" <asudhakar...@r ediffmail.comwr ote:
I would like to know how this is happening internally, suppose that if we
have to write our own Memory Manager which handle these ?
Consider going through the C++ FAQ lite - http://www.parashift.com/c++-faq-lit...html#faq-16.14 This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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//////////////////////////////////
void operator delete(void* mem,int head_type) {
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/////////////////////
void* operator new(size_t sz, int head_Type) {
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