01-10-2013
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I posted a question on date intervals about a month back asking about how I could be able to go about a user entering the starting year/month/day and an ending year/month/day and then the script automatically cycling through each day of each month of each year that the user has specified.
I... (7 Replies)
Discussion started by: yongho
7 Replies
2. Shell Programming and Scripting
In my server migration requirement, I need to compare if one file on old server is exactly the same as the corresponding file on the new server.
For diff and comm, the inputs need to be sorted. But I do not want to disturb the content of the file and need to find byte-to-byte match.
Please... (4 Replies)
Discussion started by: krishmaths
4 Replies
3. Shell Programming and Scripting
Hi All
Can anyone please suggest me how to remove the last byte from a falt file .This is from the last line's last BYTE.
Please suggest me something.
Thank's and regards
Vinay (1 Reply)
Discussion started by: vinayrao
1 Replies
4. Shell Programming and Scripting
divide input values into specified number (-100 or -200) according to the key (a1 or a2 ....)
For ex: if we give -100 in the command line it would create 100 number intervals (1-100, 100-200, 200-300) untill it covers the value 300 in a1.
Note: It should work the same even with huge numbers... (3 Replies)
Discussion started by: ruby_sgp
3 Replies
5. Ubuntu
Hi
I am new to expect. Please if any one can help on my issue its really appreciable. here is my issue:
I want expect script for random passwords and random commands generation.
please can anyone help me?
Many Thanks in advance (0 Replies)
Discussion started by: vanid
0 Replies
6. Shell Programming and Scripting
Need to use dd to generate a large file from a sample file of random data. This is because I don't have /dev/urandom.
I create a named pipe then:
dd if=mynamed.fifo do=myfile.fifo bs=1024 count=1024
but when I cat a file to the fifo that's 1024 random bytes:
cat randomfile.txt >... (7 Replies)
Discussion started by: Devyn
7 Replies
7. UNIX for Dummies Questions & Answers
There was an upload recently on generating a pseudo-random file when /dev/random does NOT exist.
This does not need /dev/random, /dev/urandom or $RANDOM either...
(I assume $RANDOM relies on the /dev/random device in some way.)
This code uses hexdump just because I like hexdump for ease of... (2 Replies)
Discussion started by: wisecracker
2 Replies
8. UNIX for Dummies Questions & Answers
Hi all,
I hope you can help me with the following question:
I have multiple tables like this:
Chr Start End Zygosity Gene
chr1 153233510 153233510 het LOR
chr1 153233615 153233615 hom LOR
chr1 153233701 153233701 hom LOR
chr1 ... (5 Replies)
Discussion started by: lsantome
5 Replies
9. UNIX for Dummies Questions & Answers
Hello
I created 3 files by:
dd if=/dev/urandom bs=1024 count=1000000 of=./testfile1
dd if=/dev/urandom bs=1024 count=5000000 of=./testfile2
dd if=/dev/urandom bs=1024 count=10000000 of=./testfile3
Now I want to know how to make a change in a specific byte and/or line of theses files? (2 Replies)
Discussion started by: frhling
2 Replies
10. UNIX for Dummies Questions & Answers
hi all,
I wish to calculate the length between intervals whose are defined by a starting and an end possition. The data looks like this:
1 10
23 30
45 60
70 100...
The desired output should be:
13 # (23-10)
15 # (45-30)
10 # (70-60)...
I donīt know how to operate with different... (2 Replies)
Discussion started by: lsantome
2 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)