Hi,
I have a program that searches for a particular string patten. I am however having difficulty passing the varible $i (in a loop) as the string pattern to replace. Using either perl or sed search and replace statements, I get the same kinda result. For example, using the perl:
for i in... (3 Replies)
I'm working on making a menu system on an HP-UX box with Bash on it. The old menu system presents the users with a standard text menu with numbers to make selections. I'm re-working the system and I would like to provide something more akin to iterative search in Emacs.
I have a list of 28... (2 Replies)
Hey, im trying to validate a user input and need some help. The input needs to be just a single letter. Im using a case to so this eg:
read answer
case $answer in
*) echo "OK"
;;
*) echo "This is a number"
read answer
;;
*) echo... (2 Replies)
Hi all, I currently have a script which uses read -p for user interaction. e.g.
read -p "New user? " user
Is it possible to have it so if the user enters nothing and just presses return it can resort to a specified value instead?
Thanks! :) (5 Replies)
I am starting to learn how to use bash and I would like the script to do the following:
Asks the user for his/her name
Asks the user for one number
Asks the user for another number
Then it adds the two numbers,
Also multiply the two numbers
I have the part where you get the name, and I... (3 Replies)
hi all,
i have a script that need user input provide all variables that needed to complete a job.
this is my current script:
echo "type file source and it full path :"
read INPUTFILE
if || ;
then
echo "ERROR: you didn't enter a file source or file source is not... (2 Replies)
Below is a simple script to prompt for user input while suggesting an editable default value at the prompt:
shortname=user1
read -e -i $shortname -p "Please enter the username you would like to add: " input
USERNAME="${input:-$shortname}"
Please enter the username you would like to add:... (3 Replies)
I have the basic command written in bash
for element in 1 2
do
if ]; then
set el = "t"
else
set el = "p"
fi
done
but i get the following error
syntax error near unexpected token `for'
` for element in 1 2'
What should i do differently? (3 Replies)
Discussion started by: ncwxpanther
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)