hey, i'm trying to write a shell script which accepts:
operand operator operand
then, the script would see which operator it is (using case) and calculate it...
but i dont know how to do it correctly with $1 $2 $3... (eliminating accepting separate inputs) (1 Reply)
I'm reading from a file that is semi-colon delimited. One of the fields contains 2 spaces separating the first and last name (4th field in - "JOHN<space><space> DOE"):
e.g. TORONTO;ONTARIO;1 YONGE STREET;JOHN DOE;CANADA
When I read this record and either echo/print to screen or write to... (4 Replies)
This reads single keystrokes and produces an output:
#! /bin/bash
while : ; do
read -s -n 1 >/dev/null 2>&1
echo ${REPLY}
done | awk '{print}'
This second one don't. Even though these examples make no sense; the real code is more complicated. Who knows what the problem is... (2 Replies)
Hi all,
My search karate must be weak because I'm about certain something very like this has been asked and answered here many times. I'll give you the exact scenario I've wasted a few hours of my Saturday on: :wall:
I'm trying to read through a very large number (~200) of router and... (28 Replies)
Can we input two variable on single line that separate by space example user input "list jpg" it will list all jpg files in current directory (3 Replies)
Hi Guys,
I need to append some data to a new file, but i need to make sure that when i use to >> command again.I dont go to the new line. i append the data on the same line.
Please help regarding the same.
Thanks in advance..!!! (3 Replies)
Hi
I am new to writing script and want to use a Bash Piped while-read and read from user input.
if something happens on server.log then do while loop or if something happend on user input then do while loop.
Pseudocode something like:
tail -n 3 -f server.log | while read serverline || read... (8 Replies)
Dear Friends,
I am looking for a shell script to merge input files into one file .. here is my idea:
1st paramter would be outfile file (all input files content)
read all input files and merge them to input param 1
ex: if I pass 6 file names to the script then 1st file name as output file... (4 Replies)
Example input:
John:Shepherd:770-767-4040:U.S.A:New York
Mo Jo:Jo Jo: 666-666-6666:U.S.A:Townsville
Expected Output:
First Name: John
Last Name: Shepherd
Phone Number: 770-767-4040
Country: U.S.A
State: New York
First Name: Mo Jo
Last Name: Jo Jo
Phone Number: 666-666-6666... (10 Replies)
Hi,
I am working on a script, which requests users to enter input.
Ex: read -p "Please enter your email id:" email
I don't want users skipping this entry, this has to be mandatory.I dont want to proceed without input.
I can do a check if variable $email is empty and proceed if not.But, i... (7 Replies)
Discussion started by: aravindadla
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)