Longhand, quick and dirty, assumes a string length greater than 3 characters.
OSX 10.7.5, default bash terminal...
EDIT:
Due to ambiguity in the OP's original post this assumes first TWO and last two characters.
Last edited by wisecracker; 08-06-2015 at 05:27 PM..
Reason: See above...
what is the sed command to remove the first two characters of every line of a text file?
each line of the text file has the same amount of characters, and they are ALL NUMERIC. there are hundreds of lines though.
for example,
>cat file1.txt
10081551
10081599
10082234
10082259
20081134... (20 Replies)
Hi friends,
I have a doubt, I am not sure whether it is possible ah nu.
I am having a file(sample.txt) which contain 5 lines.
I want to remove 1st line in the file and save the file with same old name (sample.txt).
For removing 1st line i am using
sed 1d filename
But dono how to... (3 Replies)
I tried using below command
tr -cd "" < InputFile.xml > output.txt ============= This removes all the tabs/newline/extra spaces from a file
it successfully removed all the extra spaces,tabs and new line characters but then the complete file become one record. I want to retain one new line... (1 Reply)
Hi,
I have a file with lines like below.
I need to remove first few characters from each line until a date format is found.
05/06/12 20:47:02 GUMGUY@98.192.174.74{42B42A72AC955F5926621273E3A15059.tomcat2}TP-Processor15 LogExchUsage: ERROR:
05/06/12 20:47:02... (8 Replies)
I have a the following line
22.152.25.36 - K##### "GET /DGGKE/GetMail.do;jwebsphere=FADFFFGSFGSFGSDGFSDFGSDFGSDF HTTP/1.1" 200 44948
Need a cut command which should give me the below output
22.152.25.36 - K##### "GET /DGGKE/GetMail.do HTTP/1.1" 200 44948
Note: The value of jwebsphere can... (6 Replies)
I have one requirement to delete all lines from a file if it matches below scenario. File contains three column. Employee Number, Employee Name and Employee ID
Scenario is: delete all line if Employee Number (1st column) contains below
1. Non-numeric Employee Number
2. Employee Number that... (3 Replies)
I have a test file with the following format, It contains the username_date when the user was locked from the database.
$ cat lockedusers.txt
TEST1_21062016
TEST2_02122015
TEST3_01032016
TEST4_01042016
I'm writing a ksh script and faced with this difficult scenario for my... (11 Replies)
here's what im trying to do.
i have a file containing lines similar to this:
data.txt:
1hsRmRsbHRiSFZNTTA1dlEyMWFkbU5wUW5CSlIyeDFTVU5SYjJOSFRuWmpia0ZuWXpKV2FHTnRU
1lKUnpWMldrZFZaMG95V25oYQpSelEyWTBka2QyRklhSHBrUjA1b1kwUkJkd3BOVXpWM1lVaG5k... (5 Replies)
I have a file as below
Emp1|FirstName|MiddleName|LastName|Address|Pincode|PhoneNumber
1234|FirstName1|MiddleName2|LastName3| Add1 || ADD2|123|000000000
2345|FirstName2|MiddleName3|LastName4|
Add1 || ADD2|
234|000000000
OUTPUT :
... (1 Reply)
Discussion started by: styris
1 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)