Hi all,
I m relatively new to C. I have few queries related to malloc():
1. When we perform malloc(), the memory allocated dynamically comes from
the heap area of the process in concern. Well, we then say that the heap
has shrinked. my query is: Is it that the heap physically does not
shrink but the perticular nodes are marked 'ALLOCATED' and for
subsequent calls to malloc() the memory manager remembers them and does
not reference them?
2. With realloc(), if some pointer 'ptr' is pointing initially to a
perticular position in a buffer (char *buffer) then on performing a
realloc() on this buffer, what will be 'ptr' pointing to?
3. whats the maximum memory size that we can allocate dynamically by
calling malloc() ?
4. Is it valid in C to typecast a pointer? eg. code snippet... of
course int is 16 bit and long is 32 bit.
int *variable, value;
*((long*)variab le)++ = value;
*((long*)variab le)++ = value;
*((long*)variab le)++ = value;
*((long*)variab le)++ = value;
thanx in advance
Nov 29 '07
22  1982 
"santosh" <sa*********@gm ail.comwrote in message
news:fi******** **@registered.m otzarella.org.. .
cr88192 wrote:
>>
"CBFalconer " <cb********@yah oo.comwrote in message
news:47******* ********@yahoo. com...
>>cr88192 wrote:
... snip ...
and I watch as those of us born in the 80s are becomming 'old',
being rapidly replaced by those from the 90s... a few years back,
people born in the 80s were still young, and people born in the
90s were little kids...
time passes and the distant past becomes ever more detached, as
my life quickly escaped me and I become old and pointless, in a
life quickly going nowhere...
Now try the effect of being born in the early '30s. :-)
your case, or hypothetical?.. .
<snip>
>but, in time, my life will end, and I wonder if I will ever have much
of anything to show for having existed.
what of all the people younger than me possible making more impressive
achievements?. ..
one gets overrun and one gets replaced...
like middle or high schoolers or such who can pull off maybe 200 or
300 kloc/year or more?...
maybe they can write impressive stuff, or make interesting
discoveries?.. .
it has been much of a year, and my compiler has not even broken 100
kloc yet.
taking my average rate calculated earlier this year, and estimating
for a full year, it comes out to about 100kloc/year, which is probably
rather lame...
Believe it or not you still seem to be _far_ above average with regards
to programming, for someone of such youth. It _very_ impressive for
someone of 25 years of age to have written multiple compilers and GCs.
actually, I am still 23, I will be turning 24 at the end of this month.
but, yeah, I think sometimes I have inferiority issues...
(among many other things).
so, yes, ok.
I am obsessive I guess.
"CBFalconer " <cb********@yah oo.comwrote in message
news:47******** *******@yahoo.c om...
cr88192 wrote:
>>
... snip ...
>>
I remember when I was back in HS or so and heard about x86-64 (I
was like, cool, a 64 bit chip that there is actually reason to
use...), but it took so long in comming out, me getting one, and
am still waiting for good OS support, ...
Well, it looks like you are using Microsoft junk, and they will
never produce a good OS. I suspect that moving to Linux will
rapidly satisfy you.
</BLAST>
well, there was a time when I used to use mostly Linux.
one major reason I am still stuck with windows now is network-card related.
actually, it is mostly just my WiFi, and I have parents that have some
bizarre aversion to network wires...
WiFi is good for some things, but it sucks when used as a primary network...
it sucks that it is slow.
it sucks having to get stupid drivers to work.
it sucks for failing pretty much every time someone uses the microwave.
....
so, good for laptops, not so good for other things.
seeing Cat5 cables is a reasonable tradeoff IMO...
--
Chuck F (cbfalconer at maineline dot net)
<http://cbfalconer.home .att.net>
Try the download section.
--
Posted via a free Usenet account from http://www.teranews.com
Jack Klein <ja*******@spam cop.netwrites:
On Thu, 29 Nov 2007 21:50:38 +0100 (CET), ravi <no****@nospam. invalid>
wrote in comp.lang.c:
<snip>
>int *variable, value;
*((long*)varia ble)++ = value;
This is not legal C code. The cast generates an rvalue, and the post
increment operator cannot be applied to lvalues.
Of course you mean either "can only be applied to lvalues" or "cannot
be applied to rvalues" -- clearly a typo but it seems worth clearing
up.
--
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