This is shell programming assignment.
It needs to create a file called .std_dbrc contains
STD_DBROOT=${HOME}/class/2031/Assgn3/STD_DB
(which includes all my simple database files)
and I am gonna use this .std_dbrc in my script file (read the data from the database files)
like this: .... (3 Replies)
Dear all,
I am reading a file that has 1 column. While reading I must find the line references from the another file. The following shell doesn't works.
Please help
#!/bin/bash
while read filename; do
grep ${filename} fs_full.dat >> unprocfull.dat;
done < unproc.dat
But when... (2 Replies)
Hello! I think this should be an easy solution. I have a large file with many fields of data. The first field has a unique identifier (a subject number) for every record for a chunk of data. Something like this:
There were ten experimental conditions (ec), but the ec is identified by only... (11 Replies)
Hi all,
I would like to ask whether in Unix shell/perl have any functions or command to allow grep/cat/read a file inside compressed .tgz without extract it?
I know we can tar tvf a compressed tgz but this only allow we read the path/filename contained inside the tarball. If we want to read... (3 Replies)
I have two files
file1.txt
angie
mary
susan
file2.txt
angie blond
mary brunnet
susan red
christine blackI want to get this output
angie blond
mary brunnet
susan redI write
grep --file=file1.txt file2.txtand i get no results
i also wrote
cat file1.txt|while read line... (19 Replies)
Hi,
I'm trying to read a fille into a loop and grep for a string and print the last field of the string in the second file. Then redirect the output to another file but keeping the output in the same order as the original file.
I've tried using the following but the ouput from this does not... (3 Replies)
Hi All,
I am having a job and I need to send email when the job is running. On any other case (success,fail) I don't needed to send email. I check with BMC they told they dont have that in the version I am using.
So I created a dependent job and grepped for the status and sent email. My... (1 Reply)
Hi Team,
in /tmp folder i have thousands of log files i want to read each file and grep a value called "Calling This".
Each logfile name is different but it ends with .log.
How can i achieve this?
Please excuse if i did any mistake by not following forum standards. I will surely follow... (10 Replies)
I have a very big input file <inputFile1.txt> which has list of mobile no
inputFile1.txt
3434343
3434323
0970978
85233
... around 1 million records
i have another file as inputFile2.txt which has some log detail big file
inputFile2.txt
afjhjdhfkjdhfkd df h8983 3434343 | 3483 | myout1 |... (3 Replies)
Discussion started by: reldb
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)