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1. Shell Programming and Scripting
Hi people,
I would like to start a review of my config variable to check whether they have been changed and if not then there is only an echo. If they have been changed to my other commands are executed.
I hope you can help me.
with best regards
JPad
edit:
here my code
if ;... (8 Replies)
Discussion started by: JPad
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2. Shell Programming and Scripting
hi,
i want to check whether a a variable contains some value or is empty in a shell script. so if the variable contains some value i want to do some job and if the variable doesnt contain any value then i need to skip that job.
here is a sample script
read_filenames.sh contains
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3. Shell Programming and Scripting
I have a script /root/asas with following contents.
#!/bin/bash
ha=`cat /etc/passwd | grep sandra`
if ; then
echo "Sandra is in /etc/passwd"
echo "variable ha is $ha"
else
echo "Sandra is NOT in /etc/passwd"
echo "variable ha is $ha"
fi
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4. Shell Programming and Scripting
I have seen many posts for this sort of problem but I just did not know how to use it for my issue. A number is assigned to a variable and I wanted to check if it is a zero or non zero.
Example of my numbers are below:
000000000000000000000000000000000000000000000000... (8 Replies)
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5. UNIX for Dummies Questions & Answers
hi to all,
i want to check the value of a variable that it contains characters.
for example i try the following:
if then .........
i just want to check that in the specific line that is a variable called "passline" has the entry "password". But it can contain also other characters in the... (4 Replies)
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6. Shell Programming and Scripting
Hi all,
to check that a variable is not empty, I usually do:
if ; then...
or
if ; then...
what if I have a serie of variables and want to do the same test on all of them. How to do this in a single if statement?
thank you (1 Reply)
Discussion started by: melanie_pfefer
1 Replies
7. Shell Programming and Scripting
Hi
I am writing a bash script and would like to check is a variable contains a . or not
ex.
a=102 output ok
a=1.02 output not ok
Many thanks, (3 Replies)
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8. Shell Programming and Scripting
Hello All,
I have a script that will email out if the email address is specified as parameter 1.
I am using ksh, and then tried the following :
email=$1
Following did not work, I am getting error
test -z $email
test ${email:=" ") -eq " "
test -n $email
test ${?email}
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9. Shell Programming and Scripting
Hello
I want to check for NULL variable..
but this is not working..please help
thanks in advance
esham (2 Replies)
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10. UNIX for Dummies Questions & Answers
If I have a variable $X, how do I check it is a number?
Many thanks. (2 Replies)
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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)