I received a warning when I tried to compile my program that said:
warning: comparison between pointer and integer
Could you please explain to me what this means, and in what ways I could possibly fix this?
Thanks for your help! (2 Replies)
I have search the forum for an easier way to write this code. I have two separate 'if' to do this and it works but am wondering if someone knows a quick way to combine them. I want anything between 1 and 100 but not '01' or '005', '0010', etc.
if ) ]] ||
]; then
echo "Try... (3 Replies)
Hi,
I am trying to use a regular exp to match any number between 0 and 7 except 2......
I am using:
echo $myvar | egrep "{1}{1}"
Which isnt working....
Please can someone help?
Thanks
yonderboy (10 Replies)
Hi,
I am just trying to compare integer in ksh. can you please tell me what's wrong with this code... or give me suggestions on alternative.
sample code:
i=0;
if ; then
echo inside if
fi
Thanks in advance! (6 Replies)
hello,
i am writing a script that takes the UID from the PASSWD and then i want
to increse the Number by one. for the Next user.
i cannot get this to work that a variable is as interger
example:
set i = 0
set $i = $+1
it's in tcsh if it's mather (10 Replies)
Hi guys :D
I am still playing with my C handbook and yes, as you can see I have small problem as always :cool:
I wrote a C code
#include <stdio.h> #define MESSAGE 100 int main(void) { char input_mes - Pastebin.com
And when I try to compile it I get following errors from gcc
... (1 Reply)
I'm trying to write a programme which scans strings to find how many vowels they contain. I get an error saying that I'm trying to compare a pointer and an integer inif(*v == scanme){. How can I overcome this ? Also, the programme seems to scan only the first word of a string e.g.: if I type "abc... (1 Reply)
I am trying to execute something like this
file=/tmp/test.txt
firstline=$(head -n 1 $file)
value=`echo $firstline | cut -d'=' -f2`
if
then
echo true
fi
i read the first line of a file, cut to the numeric value in the first line and check if it greater than 2
but for some... (11 Replies)
Discussion started by: madhan_dc
11 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)
12-07-2011
