Now imagine if someone fed it `find /dev -type b -exec dd if=/dev/urandom of={}`.
I don't want my strings to be able to execute arbitrary code like this.
If you put that into the string variable and execute the line I posted, nothing will happen other than the tokens being placed into the positional parameters. The code in $string will not be executed.
How do you pass parameters over to another script and run the receiving script? .
Here is an example of what I am talking about.
for x in `cat Allx`
do
su myaccount -c "/temp/scripts/temp_script $x" > /dev/null 2>$1 $
done
I was expecting the tem_script to be... (1 Reply)
Hi:- I need to parse a script 3 parameters (file, subject and email address). This is what I currently have:
allargs=$*
argcount=`echo $allargs | awk -F: '{ print NF }' ` # Total Number of arguments
pdffile=`echo $allargs | awk -F: '{ print $1 }' ` # PDF/binary file to be encoded... (4 Replies)
Sceduled backups with vdump have been delayed as a mounted system had crashed while I was away for 2 weeks. Now there are 5 simultaneous vdumps running very slowly. The full system backup usually takes a whole weekend.
Can I safely kill these? (I will have to live without a backup untill next... (4 Replies)
I have a job script that runs with input parms from the command line.
job.sh -p parm1_parm2_parm3_parm4_file_1.dat
The parms are separated by _
The last parm is a file name and can have an _ in the name.
I currently use the following commands to extract the parms
parm1=`eval echo... (3 Replies)
Hi all,
Am writing a script that does a rm/mv if a file exist, however, in one scenario, one of the variables which is supposed to a variable for a directory is undefined/blank so instead of the variable resolving to /tmp/logfile.dmp, it resolves instead to / so the rm translates to a rm /... (2 Replies)
I get a strange problem here, and ask for help.
(gdb)
28 set_file_bit( file, bytePos, bitPos, argv );
(gdb) p argv
$3 = 0xbfffef5c "00"
(gdb) s
set_file_bit (file=0x804b008, bytePos=2, bitPos=2, binary=0x80490e5 "11") at util/file.c:112
... (2 Replies)
Greetings,
I need some help performing a system admin function that I have been tasked with. The request seems simple enough, but my feeling is that it might be more complicated than it seems.
Here is what i've been tasked with:
SunOS 5.10 Generic_142900-15 sun4u sparc SUNW,SPARC-Enterprise... (3 Replies)
I am using:
reboot -- cdrom
However I'm afraid of causing file system errors/corruption. I've seen many threads say that
init 6
is safer, but I need to get to CDROM.
Is there a command that is as safe as init, but can boot to cdrom, or should I not worry so much about the reboot... (5 Replies)
I wanted to know whether all files under /tmp can be safely removed. I guess that /tmp may also have temporary files for applications currently being worked on, so at the most those applications may just shut down.
I hope that my question is clear whether all files under /tmp can be safely... (5 Replies)
Discussion started by: RHCE
5 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)