And perhaps in most cases this will be sufficient:
or:
Actually, for fixed length prefixes you could use cut -c1-n
where n is the number of characters:
Hi
Can anyone what I am doing wrong while using cut command.
for f in *.log
do
logfilename=$f
Log "Log file Name: $logfilename"
logfile1=`basename $logfilename .log`
flength=${#logfile1}
Log "file length $flength"
from_length=$(($flength - 15))
Log "from... (2 Replies)
Dear All,
I have a requirement in which i have to load a file placed in FTP location onto my database. The process i'll follow is as below:
1) Get the files using FTP.
2) Create the desired load files as i have to load only 19 fields out of the 104 available in the file.
The fields i require... (7 Replies)
Dears,
i want cut the lines from a log file. Example of the log file as follows..
May 27, 2011 5:54:51 PM com.huawei.ivas.utilities.sm.client.SMDeliverContrUtil isDeliverSM
FINE:
May 27, 2011 5:54:51 PM com.huawei.ivas.utilities.sm.client.SMUtil addSysUpMsgLog
INFO: . The message content... (1 Reply)
Hi,
I am working on one script..I am having files in the below format
file 1 (each line is separated with : delimeter)
SPLASH:SPLASH:SVN
CIB/MCH:MCH:SVN
Now I want from file 1 that most left part of the first line will store in... (6 Replies)
Hi,
First of all sincere apologies if I have posted in a wrong section ! Please correct me if I am wrong !
I am very new to UNIX scripting.
Currently my problem is that I have a code file at the location /home/usr/workarea/GeneratedLogs.log :-
Code :-
(Feb 7, 571 7:07:29 AM),... (4 Replies)
Hello ppl
I have a requirement to split (cut in unix) a file (A.txt) which is a pipe delimited file into A1.txt and A2.txt
Now I have to join (paste in unix) this A2.txt with external file A3.txt to form
output file A4.txt which should be CSV (comma separated file) so that third party can... (25 Replies)
I'm a complete beginner in UNIX (and not a computer science student either), just undergoing a tutoring course. Trying to replicate the instructions on my own I directed output of the ls listing command (lists all files of my home directory ) to My_dir.tsv file (see the screenshot) to make use of... (9 Replies)
I am using : << cut / cut to comment out block of code.
Works fine on few lines of script, then it gives me this cryptic error when I try to comment out about 80 lines.
The "warning " is at last line of script.
done < results
169 echo "END read all positioning parameters"
170... (8 Replies)
Discussion started by: annacreek
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)