Hi,
I was wondering what factors will influence the maximum buffer sizes
for source and destination for memcpy(). Is their any limit to the
sizeof the buffer(hardware restricting it ?) OR any other limitations
like the compiler being used ?
Your thoughts are appreciated.
Thanks.
8  6819 
On 20 Mar 2005 19:51:16 -0800, co*******@gmail .com wrote in
comp.lang.c++: Hi,
I was wondering what factors will influence the maximum buffer sizes
for source and destination for memcpy(). Is their any limit to the
sizeof the buffer(hardware restricting it ?) OR any other limitations
like the compiler being used ?
Your thoughts are appreciated.
Thanks.
The only limitation the language places on memcpy() is the fact that
the size is specified by a value of type size_t, so obviously you
cannot copy a block of memory larger than the maximum value of size_t,
if you can manage to obtain a block larger than that.
Since both the source and destination of memcpy() must be objects that
your program has the right to access, the most likely real limitation
would be the largest object that you can create or allocate.
--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++ http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html
Jack Klein wrote: On 20 Mar 2005 19:51:16 -0800, co*******@gmail .com wrote in
comp.lang.c++:
Hi,
I was wondering what factors will influence the maximum buffer
sizes for source and destination for memcpy(). Is their any limit to the
sizeof the buffer(hardware restricting it ?) OR any other
limitations like the compiler being used ?
Your thoughts are appreciated.
Thanks.
The only limitation the language places on memcpy() is the fact that
the size is specified by a value of type size_t, so obviously you
cannot copy a block of memory larger than the maximum value of
size_t, if you can manage to obtain a block larger than that.
Could you pelase tell me where is size_t defined ??
Since both the source and destination of memcpy() must be objects
that your program has the right to access, the most likely real limitation
would be the largest object that you can create or allocate.
--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html
<co*******@gmai l.com>
??????:11****** **************@ z14g2000cwz.goo glegroups.com.. .
Jack Klein wrote: On 20 Mar 2005 19:51:16 -0800, co*******@gmail .com wrote in
comp.lang.c++:
Hi,
I was wondering what factors will influence the maximum buffer sizes for source and destination for memcpy(). Is their any limit to the
sizeof the buffer(hardware restricting it ?) OR any other limitations like the compiler being used ?
Your thoughts are appreciated.
Thanks.
The only limitation the language places on memcpy() is the fact that
the size is specified by a value of type size_t, so obviously you
cannot copy a block of memory larger than the maximum value of
size_t, if you can manage to obtain a block larger than that.
Could you pelase tell me where is size_t defined ??
go to /usr/include, grep size_t then you'll find it, it depends the OS
Since both the source and destination of memcpy() must be objects
that your program has the right to access, the most likely real limitation
would be the largest object that you can create or allocate.
--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html
modemer wrote: Could you pelase tell me where is size_t defined ??
go to /usr/include, grep size_t then you'll find it, it depends the OS
According to the C++ Standard (18.1.2), a conforming implementation will offer
the definition of size_t by inclusion of <cstddef>
Thanks for correcting my suck C++ knowledge.
BTW, where I can get what you said C++ Standard?
"Kurt Stutsman" <ks*******@NOSP AM.sbcglobal.ne t> wrote in message
news:R8******** **********@news svr14.news.prod igy.com... modemer wrote:Could you pelase tell me where is size_t defined ??
go to /usr/include, grep size_t then you'll find it, it depends the OS
According to the C++ Standard (18.1.2), a conforming implementation will
offer the definition of size_t by inclusion of <cstddef>
modemer wrote: Thanks for correcting my suck C++ knowledge.
BTW, where I can get what you said C++ Standard? http://www.techstreet.com/cgi-bin/de...uct_id=1143945
I think that will take you there. The PDF is available for $18.
Also, I should warn you not to top-post (reply on top of the previous post) on
this newsgroup.
"Kurt Stutsman" <ks*******@NOSP AM.sbcglobal.ne t> wrote in message
news:Vx******** ****@newssvr21. news.prodigy.co m... modemer wrote: Thanks for correcting my suck C++ knowledge.
BTW, where I can get what you said C++ Standard?
http://www.techstreet.com/cgi-bin/de...uct_id=1143945
I think that will take you there. The PDF is available for $18.
Also, I should warn you not to top-post (reply on top of the previous
post) on this newsgroup.
Thanks a lot. I sometimes forget to move cursor to the bottom because
outlook express makes the default on the top. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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