Show us the output from the command:
(note that the option is the digit one; not the lowercase letter ell). And highlight the ? characters you are trying to replace. And, also show us the output from the command:
so we can see the characters that are being printed as question marks by ls when output is directed to a terminal. (The quotes around the ls are to avoid any aliases that might be in place.)
We develop a file in windows and move to unix box as a part of deployment. When we do this, we get ctrl-M(^M) character added to the file. So we need to remove ctrl-M(^M) character from all the files from deployment folder and all subfolders folder. Currently we move to individual folders and... (5 Replies)
I wanted to Replace if 20th Char is space then Replace by X ..
12345678901234567890
AAAA HEXW PROGRM01 (Ended by 3 Spaces ) Followed by junk(can be spaces als)
BBBB HEXW PROGRM01 A0121225001 (Ended by 3 Spaces)Followed by junk
I have Tired some thing of this sort ...
cat... (4 Replies)
Hi All i have a file that is to big for vi and is a multiple line record
3999||20090127163547796|196.46.162.250|1028|196.207.40.112|2152|00:0C:31:BB:25:5
4|00:00:0C:07:AC:06|655016000575511|05||3C65|0D029C1D|||00644B5A|||||||||||inter... (5 Replies)
Compiling xpp (The X Printing Panel) on SL6 (RHEL6 essentially):
xpp.cxx: In constructor ‘printFiles::printFiles(int, char**, int&)’:
xpp.cxx:200: error: invalid conversion from ‘const char*’ to ‘char*’
The same error with all c++ constructors - gcc 4.4.4.
If anyone can throw any light on... (8 Replies)
I need a script to take the filename of every file in a directory and substitute that file name for whatever is on the first line of the file. There may or may not be anything on the line, but I want the line to be the same as the file name. Most of the script tools I have used are non-destructuve,... (14 Replies)
Hi,
I Installed mysql on my CentOS 6.2 Server. But when I tried to change the location of /var/lib/mysql to another directory. I can't start the mysql. Below is what I've done
yum install mysql mysql-server mysql-devel
mkdir /path/to/new/
cp -R /var/lib/mysql /path/to/new
chown -R... (1 Reply)
Hello,
I have some problem in counting char of word, sum and change. I'm not sure shell script can do this.
Input data:
Sam1 BB BB AA AA BB BB BB
Sam2 BB BB AA AA AB AB AB
Sam3 BB BB BB AA BB BB BB
Sam4 AB AB AB AB AB AB AA
Sam5 BB BB AA AA BB BB -- If I count in column 2, B is 9... (3 Replies)
I am trying to do the following task :
export ENV=aaa
export ENV_PATH=$(cd /apps | ls | grep $ENV)
However, it's not working. What's the way to change to directory and search some file in that directory in single command
Please help. (2 Replies)
Given a directory containing say a few thousand files,
please output a list of all the names of the files in the directory that are exactly the same, i.e. have the same contents.
func(a_directory_name) output -> {“matches”: , ... ]}
e.g. func(“/home/my/files”) where the directory... (7 Replies)
Discussion started by: anuragpgtgerman
7 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)