I have a question. Take the following statement
awk -F\| '{print $21}' testfile | sed 's/\//\\/g' > newfile
This will grab the 21st column of a | delimited text file, replace the forward slashes "/" , with back slashes "\", and redirect the output newfile. Now, how do I get the output... (4 Replies)
Hi,
Below is a small piece of my Korn shell script - what i am trying to do is substitute all occurrences of the word given by the ${src} parameter with the word given by the ${dest} parameter in that particular textfile. But i get the errors below...
for i in `ls... (19 Replies)
Hi,
$ echo 1 titi | sed -e "s/1/$(echo \&)/"
1 titi
but
$ echo 1 titi | sed -e "s/1/$(date \&)/"
date: invalid date `&'
titi
how can i do for handle '\&' with date ?
Thx (7 Replies)
Hi.
I'm going to learn scripting and i have the following topics on the list: sed, awk, shell scripting, perl.
My question is, whehter i should learn sed and awk? Aren't this tools outdated?
Although i see that GNU upgrade it's versions of these tools from time to time.
And, the next... (9 Replies)
Hello everyone,
i wonder if someone could give me an advice regarding the following problem using sed.
Given ist a structure as shown below:
<aaa>text1<b>text2</b>text3<c>text4</c>text5</aaa>
Now I want to change the outer tag from "aaa" to "new" and replace all tags inside the outer tags... (4 Replies)
I am searching for a specific pattern and replacing with ( ) for matched pattern .I am not getting the expected result .....
Here is the file
cat test
cool
change
Frinto Francis
Frinto cool
change Attitude
/usr/bin
sed 's/*/( & )/' test
( cool )
( change )
( )Frinto Francis... (2 Replies)
Hi,
I can't seem to understand what the sed and & do.. Why is the set of numbers appear twice ? how the command really work ?
echo "123 abc" | sed 's/*/& www &/'
Output:
123 www 123 abc (3 Replies)
I want to know the working of & here step by step using sed command. (1 Reply)
Discussion started by: Preeti07
1 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)