I want to grep from a file an exact character match.
I tried grep -c "$a $b" $file
where a=6 and b=2
the problem is that I get: 6 2 and 6 20
I just need a count of the occurrence.
I'm using the Bourne shell.
I've also tried grep -c '$a $b' $file;
not sure how to do this - any suggestions? (3 Replies)
Hi Folks,
I have this windowed applescript application I use for sending out emails, it uses the Postfix daemon buit into my Mac Os X box, and a 3 SMTP servers (out of hundreds I send emails to) were refusing my messages replying "host smtp2.braspress.com.br said: 550 Requested action not... (2 Replies)
Please help. This simple problem is really stumping me.
Is there are way to find absolute pathnames for all files on your system that are longer than 100 characters?
I'm using bash shell to attempt it, but have come up with nothing so far.
I appreciate any help offered.
Nauty (2 Replies)
I have a file sample.txt with the below contents:
Aaa - providioning add ||
dev - reeec
dev kapl ||
ball - HERO ||
bal - provisioning pro ||
for given name i need the output to be the contents between - and || (excluding both)
for eg : input - Aaa
output -... (10 Replies)
Hi,
Is there anyway to find the junk characters in a file.Consider the file has data as given below:
123|abc^M|Doctor^C #record 1
234|def|Med #record 2
345|dfg^C|Wrong^V #record 3
The junk characters are highlighted and this is a pipe delimited file.
Is there anyway to... (20 Replies)
Hi, I have a series of files (upwards of 500) the filename format is as follows
CC10-1234P1999.WGS84.p190
each of this files is in a directory named for the file but excluding the extension.
Now the last three numeric characters, in this case 999, can be anything from 001 to 999, I need to... (3 Replies)
Hi, I have a series of files (upwards of 500) the filename format is as follows
CC10-1234P1999.WGS84.p190, all in one directory.
Now the last three numeric characters, in this case 999, can be anything from 001 to 999.
I need to move some of them to a seperate directory, the ones I need to... (5 Replies)
After spending sometime playing around with my script I just cannot get it to do what I want. So I decided to ask. My file looks something like this:
I am using the following code to extract sequences that contain dashes
awk '/^>/{id=$0;next}{if (match($1,"-")) print id "\n" $0}' infile
... (17 Replies)
Hi All,
Assuming i have got a file test.dat which has contains as follows:
Unix = abc def fgt jug
111 2222 3333
Linux = gggg pppp qqq
C# = ccc ffff llll
I would like to traverse through the file, get the 1st occurance of "=" and then need to get the sting... (22 Replies)
Hi....I need one help....
I'm having a files which is having the data as follows...
a
b
c c
d d d
e
f
Now I need to find out distinct characters from this file and the output should be as follows -
a
b
c
d
e
f
Can you please help me on this? I'm using KSH script. (18 Replies)
Discussion started by: Krishanu Saha
18 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)