We're making the field ending "[" part of a "bracket expression" (c.f. man regex) by treating itself as the opening bracket, adding the char (the "[") and the closing bracket as char constants in the second sub statement. We need to add a space when substituting $9 to maintain the filed length and thus the $0 formatting.
Hi ,
I have a problem , I need to devlope a script where in the user inputs file name , line number , and character position , and a substitution variable , the character at that character position should be substituted by the substitution value
for ex
say i have a file
abc.txt
which... (3 Replies)
Hi
I have to replace in around 60 files a word an replcae it by another
Suppose all the files have a word intelligent i want to replace it by idiot
I am planning to use sed for executing this job
sed 's/\intelligent/idiot/g'
I plan to have a file (test.txt) which contains... (1 Reply)
Hello. I'm trying to delete one character in determinate position.
Example:
qwEtsdf123Ecv34
<delete character in positión 3>
Result:
qwtsdf123Ecv34
Plase, help me.
Thanks (4 Replies)
Hi Gurus,
I am working with a korn shell script. I should replace in a very great file the character ";" with a space.
Example:
2750;~
2734;~
2778;~
2751;~
2751;~
2752;~
what the fastest method is? Sed? Awk?
Speed is dead main point, Seen the dimensions of the files
Thanks (6 Replies)
I'd like to remove (do a pattern or precise replacement - this I can handle in SED using Regex )
---AFTER THE 1ST Occurrence ( i.e. on the 2nd occurrence - from the 2nd to fourth occurance ) of a specific string : type 1
-- After the 1st occurrence of 1 string1 till the 1st occurrence of... (4 Replies)
Sample file:
This is line one,
this is another line,
this is the PRIMARY INDEX line
l ;
This is another line
The command should find the line with “PRIMARY INDEX” and remove the last character from the line preceding it (in this case , comma) and remove the first character from the line... (5 Replies)
Hi,
1/
i have file test.txt
1 Jul 28 08:35:29 2014-07-28 Root::UserA
1 Jul 28 08:36:44 2014-07-28 Root::UserB i want to delete the seconds of the file, and the Root:: and the output will be:
1 Jul 28 08:35 2014-07-28 UserA
1 Jul 28 08:36 2014-07-28 UserB 2/i have another file test2.txt:... (8 Replies)
i am trying to prepare a train and test dataset, for which i need to randomly split the data into corresponding folders (train,test)..
I began on a simple script, but seem to get som weird error messages, that i cannot make sense of?..
what am I doing wrong?
#!/bin/bash
RED='\033]
then... (13 Replies)
Hi Friends,
I have somefiles like
20180720_1812.tar.gz
20180720_1912.tar.gz
20180720_2012.tar.gz
20180720_2112.tar.gz
20180721_0012.tar.gz
20180721_0112.tar.gz
20180721_0212.tar.gz
20180721_0312.tar.gz
in a directory and so on..these files gets created every 3 hours where as... (28 Replies)
Hi
Please dont consider this as duplicated post..
I am using below pattern to find delete files to bringdown disc size.. however how i can make sure ist going to correct folder and searching for files... while print "echo rm " LastFile correctly print files names for deletion, but when i... (7 Replies)
Discussion started by: onenessboy
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)