Hi.
Can I extract the last 3 characters from a given string using sed ?
Why the following doesn't work (it prints the full string) :
echo "abcd" | sed '/\.\.\.$/p' doesn't work ?
output: abcd
Thanks in advance,
435 Gavea. (7 Replies)
Hello folks
I want to extract data between certain tag in XML file using 'sed'
<xml>
.........
..........
<one>XXXXXXXXXXXXXXXXXXXX</one>
......
Anyone ?Thank you (7 Replies)
Given the following text in a file named extract.txt:
listenPort:=25
smtpDestination:=2
enableSSL:=
I am trying to extract only the value 2 following smtpDestination:=
Someone had suggested I use:
sed -e "s/^smtpDestination:=\(.*\)$/\1/" extract.txt
but this returns:
listenPort:=25
2
... (2 Replies)
I am trying to pull certain pieces of data out of a line of a file that matches a certain pattern:
The three pieces that I want to pull out of this line are the only occurrences of that pattern within the line, but the rest of the line is not consistent in each file. Basically the line is... (3 Replies)
Hi,
Can anyone help me in understanding how the below code works?
echo "texxt" | sed 's///' gives output exxt, ideally it should give xxt. as this should remove the chars which is not x.
echo 'x_a_b_a_c_a_d' | sed 's/.*\(a\)/\1/'
gives output as a_d, which should be 'a' as it's the only... (2 Replies)
Hello,
I need some help,
I got a CSV file called test.txt with this text in it :
08/02/2011;0,677;0,903;1,079;1,336;1,513;1,683
There's only a line and i need to copy theese numbers into variables :
0,677
0,903
1,079
1,336
1,513
1,683
The output file should look like this... (5 Replies)
I have a file containing strings such as:
UPDATE PS_CA_BI_FF2_TA3 SET DELETE_ME = 'Y' WHERE PROCESS_INSTANCE
BI.LAST_UPDATE_DTTM FROM PS_CA_BP_LINES LINE, PS_INTFC_BI BI WHERE
EXISTS ( SELECT 'X' FROM PS_CA_BILL_PLAN BP WHERE BP.CONTRACT_NUM
%Select(COUNTER4) SELECT COUNT(*) FROM PS_INTFC_BI... (2 Replies)
My source file is structured with two words on each line
word1 word2
word1 word2
I am using sed and awk to grab groups of specific lines
line=`awk 'NR>=4 && NR<=7' file1`; echo $line
line=` sed -n '1,5'p file1`; echo $line
The resulting output is
word1 word2 word1 word2 word1... (1 Reply)
I have number 192.168.21.8.
I want to extract from this number with sed 21 and 8 to variables a and b. Any Ideas?
I did like 's/\(192.168.\)/ /' but its wrong :( (6 Replies)
Hello.
from a text file, I want to get only the first word ( before blank ) following code=
grep -i -e "WORD1" "/path/to/text/file.txt | sed -n 's/WORD1\+//p' | sed -n 's/code=/\1/p'
return an error.
sed: -e expression #1, char 12: invalid reference \1 on `s' command's RHSFor debugging... (12 Replies)
Discussion started by: jcdole
12 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)