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Hi ,I am trying to assign string to variable ,but it doesn't work
Also could you show me different ways to use grep,(I am trying to get the first,second and first column form file,and I am counting the chars)
let name=`grep "$id" product | cut -c6-20` (25 Replies)
Hi All,
I am using a bash shell and want to the following thing.
A process sends the following string to my script
BACKUP_FAIL_REASON="Failed - Application Dump CDMACA-0:grep: /opt/nortel/ca/data/1245184/sd00/image1/S110907070708HIS... (4 Replies)
Hello guys,
here is my problem:
I got a shell script which is called by an external piece of software, the external software is not under my control. The software passes data as an argument to my script like
./bla.sh 'service;1234567890;ok;hostname;some text here'
I need to pass the... (3 Replies)
In my script I'm retrieving a parameter through an API call. I need to trim some things out of the result so I can use it as a parameter to pass to another process. I've got it working but it's pretty kludgy and I'm hoping someone can help me with a better way.
This is the code that retrieves... (2 Replies)
Hello,
Why is this not working in a script?
files="test.fsa"
echo $files
for file in $files
do
if
then
echo "$file does not exist."
fi
run a command
done
I get an error saying (3 Replies)
Hello All,
I am learning BASH scripting and I would appreciate any help with a small problem I am having...
I am writing a script that builds a simple hosts file for DNS reasons related to a piece of software called netdb by parsing another application's config files for IP's and their... (4 Replies)
Hi,
I've been stuck for several days on this. Using grep on a command line, I can use quotes, eg...
grep 'pattern of several words' filename
I want to do this in my bash script. In my script I have captured the several command line arguments (eg arg1 arg2) into a variable:
variable=$@
I... (2 Replies)
I'm trying to write a basic bash script that takes input you give (what directory, if any, what name, if any ....) and passes the information to find.
I'm trying to just create a string with all variables and then pass it to find. So far I have this extremely simple:
#!/bin/bash -f
... (2 Replies)
Hi, I have a variable with grep output like this:
WORDS=$(grep -r -c -i -E "palindrom" /"$DIRECTORY"/)
so "echo "$WORDS"" could be:
//directory/file1.txt:0
//directory/file2.txt:0
//directory/file3.txt:3
//directory/file4.txt:1
//directory/file5.txt:0
I need to "sed" my variable... (3 Replies)
Hi. I'd like to remove all values in a string variable that also exist in a second variable. What is the appropriate approach to take here? I can use a 'For' loop and check each element and then populate a new string. But is there a cleaner, simpler way?
E.g. I have the following 2 variables ... (19 Replies)
Discussion started by: user052009
19 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)