We are getting field 2 and printing it in the terminal.
Will it be possible to resend the field 2 values back to the same file temp.txt replacing the existing data in that file?
Ok, I'm stumped and can't seem to find relevant info.
(I'm not even sure, I might have asked something similar before.):
I'm trying to use shell scripting/UNIX commands to extract URLs from a fairly large web page, with a view to ultimately wrapping this in PHP with exec() and including the... (2 Replies)
Hi All,
This is Ram. I'm new to this forum & new to shell scripts as well. I've a requirement in which I want to extract a substring from a given string based on last occurance of a character.
for eg.
I have a string of a file name with absolute path like... (2 Replies)
hi
i need to name a file with a substring of a another file name.
i.e. if the old filename is abc.txt , the new filename should be abc_1.txt
i should get the substring of the file name and then name the new one
please let me know how to do it (4 Replies)
Hi all.
I need help with a command to locate a substring from a string.
My problem is I am passing a direcotry name as a command line argument and I need to ensure that user should not pass certain directories.
E.g ther are Directories under ==> /opt/projects/* which should not be passed... (3 Replies)
Hi awk and sed gurus,
Please help me in the following.
I have the following entries in the file
ABCDErules
AbHDPrules
ABCrules
--
--
and other entries in the file.
Now, I want to extract from the file that contain entries for *rules and process it separately.
How can i do it... (6 Replies)
Hi,
I have string in variable like '/u/dolfin/in/DOLFIN.PRL_100.OIB.TLU.001.D20110520.T040010'
and i want to conevrt this string into only "DOLFIN.PRL_100.OIB.TLU.001.D20110520.T040010" (i.e file name).
Is there any command to extracting string in some part ?(rather than whole path)?
... (5 Replies)
Hi all,
I need to extract the "abcdef" from the below string Digital_abcdef_20130103.txt.gz
The length of the "abcdef" will be changing but it will be always after the word Digital_ and before the second underscore
help in this regard is highly appreciated (3 Replies)
Hi,
I am new to Unix. I am trying to extract a substring from an input string: Ex -
input string: deploy_v11_9_1
i want to extract and store the value v11_9_1 from the input string in a new variable.
I am using following command in my shell script file:
echo "Enter the folder name u... (5 Replies)
Hi All,
I'm facing issue wherein I have 2 character string like 'CR' and 'DR' and I want to extract just 1st character but am unable to do it. I tried below options but they are returning me 2nd character only,
var="CR"
echo ${var:1}
returns just "R"
echo ${var:0}
returns "CR"
... (5 Replies)
Hello.
First best wishes for everybody.
here is the input file ("$INPUT1") contents :
BASH_FUNC_message_begin_script%%=() { local -a L_ARRAY;
BASH_FUNC_message_debug%%=() { local -a L_ARRAY;
BASH_FUNC_message_end_script%%=() { local -a L_ARRAY;
BASH_FUNC_message_error%%=() { local... (3 Replies)
Discussion started by: jcdole
3 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)