Hi all,
I am new to UNIX, so sorry if my question seem stupid to u.
well i want to replace the first character of first 30 lines of a file, only if the first character is h.
and
in anothe script i want to replace a particular string/character say hello/h of a file.Condition: It should... (1 Reply)
Hello
I am a beginner in shell script.
I was trying to find a way to replace multiple lines of a file with different set of multiple line.
sed -n '/begin/,/end/p' < sample1.txt >test.txt
UNEDITED=`cat test.txt`
vi test.txt
EDITED=`cat test.txt`... (2 Replies)
Hi all,
I have two parameter blocks in a configuration file, file1.conf.
First parameter block starts with PWAT-PARM1 and
ends with END PWAT-PARM1.
Second parameter block starts with PWAT-PARM2 and
ends with END PWAT-PARM2 (please see below in file1.conf).
file1.conf is fixed width... (8 Replies)
Hello,
I have 8 lines containing these unique words in both files
645147468537
673962863160
673962864957
691717701950
707917019907
790085591726
792975507744
852174812753
file.dat.orig (has 1000 lines) and file.dat(has only 8 lines)
I want to replace those lines in file.dat.orig by... (1 Reply)
Hi everybody,
I am a newbie in shell scripting and I'm trying to write a script which reads lines from a file, searching some of this lines to change a specified number. I want to replace the line for another in the file.
I have to replace multiples lines, so I have a for. Now I am trying with... (1 Reply)
Replace first 3 characters in a unix file (say replace "A&B" with "C&D") in all lines of the file. Need a sed or awk script to do this. Kindly help!
-Kumar (4 Replies)
I have a file lake this
cat ex1.txt
</DISCOUNTS>
<B2B_SPECIFICATION elem="0">
<B2B_SPECIFICATION elem="0">
<DESCR>Netti 2 </DESCR>
<NUMBER>D02021507505</NUMBER>
</B2B_SPECIFICATION>
<B2B_SPECIFICATION elem="1">
<DESCR>Puhepaketti</DESCR>... (2 Replies)
OS version: RHEL 6.7
Shell : Bash
I have a file like below
$ cat pattern.txt
'T_PKT_HEADER'
'T_ORD_ITM_LOYX'
'T_ORDERITM_TRMS'
'T_ORDER_ITEM'
'T_ORDER_ITM_PRI'
'T_ORDER_ITEM_OM'
'T_ORDER_ITEM_XA'
'T_ORDER_ATT'
'T_ORDER_ACTNSET'
'T_ORDER_XM'
'T_ORDER_X'
'T_ORDER_TNTX'... (7 Replies)
Discussion started by: kraljic
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)