Hi there could someone explain what is happening in the following function/statement for me, im just a little confused
code = 'BEGIN{FS=","}
{
printf ("%-11s,%s%s%s,%07.2f,%14s,%-3s\n",$1,substr($2,9,2),substr($2,6,2),substr($
2,3,2),$9,$10,$12)
}
this function is called later in the... (2 Replies)
I am trying to print the remaing fields and field numbers beginning with a field 'xyz'
#cat abc
test1:test2:xyz:test3:test4:test5
#cat def
test1:test2:test3:xyz:test4:test5
desired output is to be able to print NF and any trailing fields separated by':'
test3 3
or
test4 3
or
test5... (4 Replies)
Hi,
Have to check file names in some given directory.
SO, What is the right syntax here:
*$3*=="'$object_list'" - just wanted to check if $3 is in the object_list.
And also, Do I need so many quotes around? (5 Replies)
When i tyr this, it gives me a syntax error...i tried removing quotes,removing spaces,replacing -eq with '='.. Can somebody suggest that is the problem?
if ]; then (4 Replies)
Hi All,
can some one figure out the syntax issue here. How to overcome this?
#!/bin/sh
$ HFR_MAIL=NO
$ PRP_MAIL=NO
$ MC_MAIL=NO
$ if && && ]; then
> echo "NO "
> else
> echo "YES"
> fi
test: unknown operator NO
$ if && && ]; then
> echo "NO"
> else
> echo "YES"
>... (4 Replies)
Hi,
Can someone give me an example of how to use zsh's ternary operator?
I tried:
# a=1
# c=( a ? "true" : "false" )
and got:
zsh: no matches found: ?
I'm running zsh 4.2 on RHEL AS 4.
Thanks!
Paul (1 Reply)
Hi
I use awk command to delete the first blanc line of a file:
awk '/^$/ && !f{f=1;next}1' infile > outfile
can somebody please explain me what the last "1'" in !f{f=1;next}1' stands for... Thansk a lot -A (3 Replies)
hi,
i have a bash script that i want to receive a a string from another bash file. But because the string has a dot in the middle it gives me an error. The error is in this line:
let valor=$1
and the value passed is rules.txt
the error is:
let: valor=rules.txt: syntax error: invalid... (2 Replies)
Hello all,
I am writing up an input file and I was hoping I could get some guidance as to how to best consolidate these 2 awk statements for 1 while loop.
Here's my input file
# cat databases.lst
#NOTE: These entries are delimited by tabs "\t"
#oracleSID name/pass
#
db11 ... (2 Replies)
split($7,a," "); date = a; time = a
split(date,d,"/"); month = sprintf("%02d",d); day = sprintf("%02d",d); year = 2000 + d % 100
split(time,t,":"); hour=t; min=t
hour >= 12? { hour=hour-12; amPm=" PM" } : amPM=" AM"
hour == 0? hour=12
time=sprintf("%02d",hour)":"sprintf("%02d",min)amPm
... (4 Replies)
Discussion started by: Michael Stora
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)