Hello everyone.
I'm writing a script in UNIX. The purpose is to get the second character from a variable that stores the system year.
This is the code:
unix_year_yy=`date "+%g"`
This will return "07" in variable unix_year_yy. How can I get the second character (7)?? (6 Replies)
Dear All,
i have a file that contains,
FROM_DATE: 06-08-2007 00:00:00 TO_DATE: 06-08-2007 23:59:59 Total number of lines: 6874154
in another file,the contain is,
FROM_DATE: 06-08-2007 00:00:00 Total number of lines: 874154
alltime i want to find the particular string... (4 Replies)
I execute command on this file and it gives o/p like this.
COMMAND $ fuser -f /clocal/sanjay/AccessMonitor
/clocal/sanjay/AccessMonitor: 1368322c
To truncate 'c', i used tr -dc "\n" but then it does't give 1368322 as O/P.
Any help ?? (7 Replies)
Hi,
I am trying to do something which I thought was very simple but still being a beginner, has proved not to be.
Input:
val1 val2 val3 val4 val5 val6
.
.
.
etc
Desired Output:
Every row in which value of val6 is a number starting with 0.0 or contains a capital E. The input... (2 Replies)
I need to check the occurrence of one string within another.
code
********************
if ;then do something done
********************
Thanks (7 Replies)
Hi
I use the below cmd to get the list of files that are modified than <temp> file in the <path> diretory
cmd:find <path> -name '*.zip' -type f -newer <temp> -print
i am getting all the list of files that are new or modified, with abs path, i want to copy all of these files to a... (3 Replies)
Hi,
I hav a string lets say aa.txt:bb:txt
length of the string can vary.. I have to keep the token inside a array and the delimiter is : plz send me the code (2 Replies)
Hi All,
I have a ouput string likes 'u8wos' or 'u10acsd' or somthing else 'u{number}{any characters}'and I want to get the number behind the letter 'u' by bash shell.
Thanks
Damon (11 Replies)
Hi All,
In ksh, am trying to get a substring stuff done. Not sure where the problem is.. can you guys guide me on this...
for instance, var1=41, and var2=4175894567, then i want to know whether var2 starts with var1.. var1 and var2 can be of any length..
VAR1=41
VAR2=419068567777... (6 Replies)
Discussion started by: nram_krishna@ya
6 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)