I have defined the class and call the sizeof(object to class) to get the size.
I expect the output of size of q and size of w to be "9" - since it is int+float+char(4+4+1)
However it returns 12. Can anybody explain why is it so??
Output as follows:
Thanks,
Ramkrix
Last edited by radoulov; 10-12-2010 at 03:55 PM..
Reason: Fixed code tags.
we know that sizeof never returns zero when used with structure
then why in this case it is returning zero
struct foo
{
char c;
};
void main()
{
struct foo f;
cout<<sizeof(f);
}
i am working on solaris 5.8
isn't the above function should return the size of empty structure (7 Replies)
hi this
i tried for getting url form mozilla window.
and also for getting mozilla object file.
is there any plz tell the way.
thanking u.
ramesh (7 Replies)
Hi All,
is it possible to find out the size of an array of structures ( without using 'sizeof' operator). The condition is we have the array of structure instant but we are not aware of the elements inside the structure.
Can someone help me out?
Thanks in advance. (18 Replies)
The below code throws the error, since the size of x = 19 is not passed to the cstrCopy function.
using namespace std;
static void cstrCopy(char *x, const char*y);
int main ()
{
char x;
const string y = "UNIX FORUM";
cstrCopy(x,y.c_str());
return 0;
}
void cstrCopy(char *x,... (3 Replies)
I am new to PHP and UNIX. I am using Apache to do my testing on a Windows Vista machine.
I am getting this error when I am trying to connect to a web service. I did a search and did not see any posts that pertain to this.
Here is my function:
<?php
function TRECSend($a, $b, $c, $d,... (0 Replies)
Hi,
I was asked this question in interview.can you people please help me out in this.
class A
{
int i;
a()
{
i=10;
cout << i;
}
}
int main()
{
A a(); // what will be the program output
}
Thanks,
Harika (3 Replies)
Hi,
There are some bewildering sizeof() questions I have in my mind. Could anyone shed some light on this?
int main() {
printf("%d\n", sizeof(main)); // Ans: 1
}
That is, the sizeof() a function identifier though it is treated internally as a pointer gives 1 byte always, why?
... (5 Replies)
Hai
how to find size of a file??
ex : /home/kiran/pdk/sample/calibre this is a path
In that I have to find size of a files in side a calibre(it is the folder) like .results or .summary (1 Reply)
How to initialize an object of class say "A", with an object of type say "B".
The following code give the error message "error: conversion from âAâ to non-scalar type âBâ requested"
#include <iostream>
using namespace std;
class B;
class A{
public:
A() { cout <<"\nA()" << endl; }
... (1 Reply)
Ignoring other considerations for a moment and in general ...
Would there be a difference in result (dot oh or execution) of:
A.
strncpy( a, b, sizeof(a) );
vs.
B.
c = sizeof(a);
strncpy( a, b, c );
My general understanding is (at least I think my understanding is) that... (10 Replies)
Discussion started by: GSalisbury
10 Replies
LEARN ABOUT DEBIAN
bup-margin
bup-margin(1) General Commands Manual bup-margin(1)NAME
bup-margin - figure out your deduplication safety margin
SYNOPSIS
bup margin [options...]
DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two
entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.
For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit
hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by
its first 46 bits.
The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits,
that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits
with far fewer objects.
If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if
you're getting dangerously close to 160 bits.
OPTIONS --predict
Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer
from the guess. This is potentially useful for tuning an interpolation search algorithm.
--ignore-midx
don't use .midx files, use only .idx files. This is only really useful when used with --predict.
EXAMPLE
$ bup margin
Reading indexes: 100.00% (1612581/1612581), done.
40
40 matching prefix bits
1.94 bits per doubling
120 bits (61.86 doublings) remaining
4.19338e+18 times larger is possible
Everyone on earth could have 625878182 data sets
like yours, all in one repository, and we would
expect 1 object collision.
$ bup margin --predict
PackIdxList: using 1 index.
Reading indexes: 100.00% (1612581/1612581), done.
915 of 1612581 (0.057%)
SEE ALSO bup-midx(1), bup-save(1)BUP
Part of the bup(1) suite.
AUTHORS
Avery Pennarun <apenwarr@gmail.com>.
Bup unknown-bup-margin(1)