I'm not familiar with this grep usage, I probably miss something, your command executed as you posted :
Code:
grep -- -v $string
grep: -8x7YTVNk2KiuY-PWG5zzzjB-zzw: No such file or directory
gives me this error. My problem is that the variable $string has content that begins with "-" . the variable $text can very well be a file with lot of content. my problem is variable $string
Hi,
variable1="This is a car"
Now I want to replace the content of variable1, "car" to "dog". Is there any simple command I can use.
Thanks.
Joseph (4 Replies)
I got a sample BASH script like this :
$ cat test
MYVAR=$1
DUMMY1="This is tricky"
DUMMY2=24
echo $
$ ./test DUMMY1
./test: line 5: This is tricky: syntax error in expression (error token is "is tricky")
**I was expecting the output as "This is tricky", ah! but no luck
**But... (2 Replies)
I have a variable that contains filenames like this:
variable="file_1.extension<blank>file_2.extension<blank>file_3.extension<blank>file_4.extension and so on"
How can I make filenames to be separated by newline: (I tried Sed but it didn't worked well)
file_1.extension
file_2.extension... (6 Replies)
Hi all,
I have a file which will be updated every half an hour and time stamp will be printed in the beginning of the updation. i just want to grep the content between every hoalf an hour.
Pls help me on this issue. how to grep contents between tim stamp?
Ex of file:
29/09/2010... (20 Replies)
I need to know if is possible to use grep to check content of a local variable, for eg. i use read index and i want to check if the index i read is in correct form, how do i do that i tried with grep but i get errors all the time dont know how to make it work.. thanks! (3 Replies)
Hello all,
I do have a variable containing one line like this:
Waiting for job XXXXXX to start
I needed to get the 'XXXXXX' literal, so I did the following:
job_interno=`echo $log_exec | sed 's/.*Waiting for job \(*\).*/\1/' `
#other stuff
Now, my variable is have more... (5 Replies)
Tricky one:
I want to do several things all at once to blow away a directory (rm -rf <dir>)
1) I want to find all files recursively that have a specific file extension (.ver) for example.
2) Then in that file, I want to grep for an expression ( "sp2" ) for example.
3) Then I want to... (1 Reply)
1) Is it possible to get tags content by grep -E ? For example title. Source text "<title>My page<title>"; to print "My page".
2) which bash utility to use when I want to use regex in this format?
(?<=title>).*(?=</title) (11 Replies)
I have some large login files that I need to extract (user)@(server) from. Where it gets tricky is that there is usually more than one '@' sign on each line(although it does have a leading space if it's not part of the (user)@(server) string), I need only the (user)@(server) section, I need only... (6 Replies)
hi i just cant figure out how can i do this ls -lt > log.txt using $PWD
what i mean is how can i get the ls command content into a file using $PWD variable? :confused: (4 Replies)
Discussion started by: chinababy
4 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)
12-08-2011
