That should not make a difference then. Are you sure it makes a difference?
But anyway, the last letter is optional, so neither statement is according to specification. The trouble is that you can't really get it to work like this, because of .* at the beginning which becomes too greedy and so the second pattern gets matched..
or
Last edited by Scrutinizer; 12-07-2010 at 04:58 AM..
Hi,
I'm trying following:echo "test line XA24433 test" | sed 's/.*X\(.*\)/X\1/'
XA24433 test While I want the output as: XA24433
I want to grab the words starting with letter X till the next space, this word can be anywhere in the line. (9 Replies)
Hi!
I'm trying to write a regexp but I have no luck...
I have a string like this:
param1=sometext¶m2=hello¶m3=bye
Also, the string can be simply:
param2=hello
I want to return the value of param2: "hello".
How can I do this?
Thanks. (3 Replies)
Hi
I need to get text that are within ""
For example
File:
asdasd "test test2" sadasds asdda asdasd "demo demo2"
Output:
test test2 demo demo2
Any help is good
Thank you (12 Replies)
Hi ,
I am learing sed
echo abc 123 def 456 | sed 's|\(*\) \(*\)|\1|'
is returning abc def 456
i was hoping abc def "\1" should only print the occurence of the first pattern
but according to my understanding it is just removing the first occurence of the second pattern... (7 Replies)
Hi all,
How am I read a file, find the match regular expression and overwrite to the same files.
open DESTINATION_FILE, "<tmptravl.dat" or die "tmptravl.dat";
open NEW_DESTINATION_FILE, ">new_tmptravl.dat" or die "new_tmptravl.dat";
while (<DESTINATION_FILE>)
{
# print... (1 Reply)
Hi all,
I want to get a substring from a string based on given delimiter, for example:
str="foo|bar|baz" with delimiter "|",
I want to get one substring at each time with the order number the substring in the whole string,
given 1 to get "foo",
given 2 to get "bar",
given 3 to get "baz",
I... (2 Replies)
Hello All,
I'm trying to extract the lines between two consecutive elements of an array from a file.
My array looks like:
problem_arr=(PRS111 PRS213 PRS234)
j=0
while } ]
do
k=`expr $j + 1`
sed -n "/${problem_arr}/,/${problem_arr}/p" problemid.txt
---some operation goes... (11 Replies)
I am learning SED and just following the shell scripting book, i have trouble understanding the grep and sed statement,
Question : 1
__________
/opt/oracle/work/antony>cat teledir.txt
jai sharma 25853670
chanchal singhvi 9831545629
anil aggarwal 9830263298
shyam saksena 23217847
lalit... (7 Replies)
Hi , I need to remove pipe character from a |^ delimeted file.
Something like |^tran|sformers||^|revenge |of fallen|^ to
|^transformers|^revenge of fallen|^...
Cold anybody please help to build the regular expression using sed .
many thanks.
Please use code tags next time for... (1 Reply)
Discussion started by: kokjek
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)