Hello,
I have a name file in Unix for example : ABC_TODAYFirst.001 and I want just capture or display the 3 first letters so : ABC.
I tried with cut -c,1-3 and the name but it displays the 3 first letters of all lines.
Can you help , Thanks a lot (8 Replies)
If in a script I am taking an input (R201) for example and assigning it to a variable, how would I change the R to uppercase if it was keyed in as r201? I can't seem to get it to work with toupper (4 Replies)
Dear all
I am still bit new in shell script area.I am writing down a shell script which I guess somewhere wrong so please kindly correct it. I would be greatful for that.
What I actually want from this shell script is that it will move all the files one by one to another server which can be... (2 Replies)
i've looked at a bunch of the date comparison threads on these boards but unfortunately not been able to figure this thing out yet. still confused by some of the way conditionals handle variables...
here is what i where i am now...
# a bunch of initializition steps are here ...... (1 Reply)
Hi,
I want to check if file(s) exist even in subdirectories and perform an action. After searching here couldn't find solution that would work, but made my own solution that works fine:
if
then
echo
egrep "$1|$2|$3" `find| grep MLOG`
else
echo "MLOG does not exist"
fiThat will check... (1 Reply)
Looking how to find only three or four letter strings using grep in a file called hello:
file contains:
TIT
TAT
RATA
ERAT
RATE
HI
RE
CA
PA
CHANGE
SANDY
ANSWER
I am using the code: (4 Replies)
I tried with sed command to create a space between namespace from the XML file. I used this syntax. Can someone tell me is this syntax is vaild?
/usr/xpg4/bin/sed -e 's/<\/^.*><^.:Errort>/<\/^.*> <^.:Errort>/g' test > test2
I dint find any changes or any space being created between... (10 Replies)
Hello Guys,
I am writing a script which check each line for how many Uppercase and Lowercase letter of a given file. Please check my script as follow:
l=0
while read line
do
echo Line `expr $l + 1` has ` tr -cd "" < $line | wc -c` uppercase letters and
`tr -cd "" < $line | wc -c`... (3 Replies)
I need to find all files and folders containing keyword from the topmost directory deep down the tree but omitting all references to keyword in web-search logs and entries, i.e. excluding search and browsing history made using web-browser1, web-browser2, web-browser3, (bypassing all entries of the... (8 Replies)
Discussion started by: scrutinizerix
8 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)