Hi ,
I have a list of files in a directory and filename format is as follows:
PQ223390
PQ876912
PQ768901
PQ398140 and so on
I want to grep the first four digits of all the files after PQ, into a file.
Ex:
2233
8769
6890
3981 and so on
Can anyone tell me the command?
thankx jazz (11 Replies)
Hi, I am currently building a PHP/MySQL database that handles our offices newsletters. Now everything works great in the alpha with only a few names in the list, but I anticipate that once we fill it up (around 10,000) that this will not work from the PHP. I already have the script echo the... (0 Replies)
I have a directory of files and each file has a random 5 digit string at the beginning that needs to be removed. Plus, there are some files that will be identically named after the 5 digit string is removed and I want those eliminated or moved.
any ideas? (17 Replies)
Hi,
I need to Change passwd for bulk servers using SSH script.
I have one server, from which i can reach all the servers without password via SSH.
There is some expect script, from which i can achieve it.
Can any one help me out here.
Thanks in advance.
Vicky (1 Reply)
Hi I have abc_ahb_one.v
abc_ahb_two.v
abc_ahb_three.v
........l
like this
-----upto
abc_ahb_ninety.v in some directory.
I need to change those file names to like below.
... (5 Replies)
Hi, all:
I'd love to use shell script to change all filenames under different folders once for all:
I've got over 100 folders, in each of them, there is a file named "a.ppm". I wanna change all these "a.ppm" to "b.ppm", and still . Visually, the directory structure looks like:
and hope... (1 Reply)
I have a filename with a bunch of periods that I want to replace with underscores, but I don't want to change the extension.
Ex: I want
file.test1.f-1.fig.eps
to be
file_test1_f-1_fig.eps
Using awk, the following line will replace ALL periods with underscores, but I want to leave the... (2 Replies)
Hi,
I have little experience on Shell scripts, I searched the forum but couldn't make out what I want.
I want to rename a set of files to a new file name
a_b_20100101
c_d_20100101
.......................
......................
I want to rename the files to
a_b_20140101... (5 Replies)
Hello,
I made a mistake in a script and now need to go back and change allot of filenames. I need to change "v4" in filenames to "v3". I was thinking of something like this.
#!/bin/bash
FILELIST=$(ls -f -R *)
for FILE in $FILELIST
do
# create new filename
... (5 Replies)
Hi All,
I am having Solaris 5.10 acting as NIS.
How do i change multiple user password in NIS in a batch.
I have predefined users with their passwords to be set:
Example:
user1 password1
user2 password2
Pls advise. (0 Replies)
Discussion started by: yogajwa
0 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)