Assign the value val to the variable var, before execution of the program begins. Such variable values are available to the BEGIN block of an AWK program.
For example:
will print to stdout:
Note that:
will print to stdout:
(I could not get an empty line to show up in a code block), as VAR has not yet been assigned.
However:
will print to stdout:
I am running a command to extract data from a database which has different text and dates (ex. 01/03/07, 05/29/08, 06/05/08). Once the file is created I need to grep for all the text with a current date then redirect the sorted data to another file then email the file out. Here is what I have right... (2 Replies)
Hi ,
I have a piece of code ...wherein I need to assign the following ...
1) A command line argument to a variable
e.g origCount=ARGV
2) A unix command to a variable
e.g result=`wc -l testFile.txt`
in my awk shell script
When I do this :
print "origCount" origCount --> I get the... (0 Replies)
Ok I have a file with hundreds of lines, four columns, space delimited, TESTB.TXT for example
TESTB.TXT
---
AA ZZ 12 34
BB YY 56 78
CC XX 91 23
DD VV 45 67
---
I want a new file that has 7 columns, the first four are identical, and the next 3 are the last three of the next line...so... (5 Replies)
I generally use yy to copy a line and then p to paste the line at end of current line.
But is there a way to paste the copied line in concatenation with the current line with out going to next line. (3 Replies)
Hi guys,
I have found your forum super useful. However, right now I am stuck on a seemingly "simple" thing in AWK. I have two columns of data, the first column in Age (in million years) and the second column is Convergence Rate (in mm/yr).
I am trying to process my data so I can use it to... (2 Replies)
I am trying to delete lines in archived Apache httpd logs
Each line has the pattern:
<ip-address> - - <date-time> <document-request-URL> <http-response> <size-of-req'd-doc> <referring-document-URL>
This pattern is shown in the example of 6 lines from the log in the code box below. These 6... (1 Reply)
Hi,
I am trying to pass awk field to a command line executed within awk (need to convert a timestamp into formatted date).
All my attempts failed this far.
Here's an example.
It works fine with timestamp hard-codded into the command
echo "1381653229 something" |awk 'BEGIN{cmd="date -d... (4 Replies)
Hi,
I have an XML file and I am tring to extract some data form it, after lot of data cleaning process, I ended up with an issue, and need your urgent support.
my current input data in below format:
<Node>xxxxxx
<Node>yyyyy</Node>
<Node>zzzzzz
<Node>12345</node>
I need... (9 Replies)
Hello All,
I am looking for help to achieve the following:
Here is the data set
1757890237|42|55570025|1468796400|0
1757890237|32|55570025|1471474800|0
1757890237|54|55570025|1474153200|1476745200
1757890237|34|55570026|1468796400|0
1757890237|44|55570026|1471474800|0... (7 Replies)
current date command runs well
awk -v t="$(date +%Y-%m-%d)" -F "'" '$1 < t' myname.dat
subtract 30 days fails
awk -v t="$(date --date="-30days" +%Y-%m-%d)" -F "'" '$1 < t' myname.dat
awk command in hp unix subtract 30 days automatically from current date without date illegal option error... (20 Replies)
Discussion started by: kmarcus
20 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)