C++ Help with file handle and simple statistics problem asking... Post: 302536673

9 More Discussions You Might Find Interesting

1. Programming

deleting a file name by its handle

All, I am having three function 1.open 2.process 3.close. Open will open a file and process will process a file and close will close the file .. I can able to close the file by its filehandler.Is there is anyway that i can get the file name by filehandle and remove it after...

2. UNIX for Dummies Questions & Answers

file statistics??

Is there any command in Unix (HP-UX) which will give me the file statistics .. e.g I have a file called r001 if I created that file on 2nd of aug 2005 and till now I changed that file contents 10 times. So how will I get the history statistic(time & date) of file modification.

3. Shell Programming and Scripting

handle file by month

Hi, I want to write a shell script which handle an oracle alert log so that when it changes month, the script generates a new file with month in the filename. Thanks in advance. Leim

4. Solaris

Before I delete any file in Unix, How can I check no open file handle is pointing to that file?

I know how to check if any file has a unix process using a file by looking at 'lsof <fullpath/filename>' command. I think using lsof is very expensive. Also to make it accurate we need to inlcude fullpath of the file. Is there another command that can tell if a file has a truely active...

5. Shell Programming and Scripting

Awk getting statistics of a grid file,

Hi , I have the following file which is basically a grid (has more than 100000 rows) LLL1 PPP1 LLL1 PPP2 LLL1 PPP3 ............... LLL1 5500 ..... LLL2 PPP1 LLL2 PPP2 LLL2 PPP3 ............... LLL1 5500 ..... L100 PPP1 L100 PPP2 L100 PPP3 ............... 2100 5500...

6. Shell Programming and Scripting

problem in using cgi_script to handle form data

Hi, I have an HTML form through which I get some text as input. i need to run a shell script say script.sh inside a perl-cgi script named main_cgi.sh on the form input. I want to write the contents of the form in a file and then perform some command line operations like grep, cat on the text...

7. Shell Programming and Scripting

Writing only timing statistics output of Timer to File

I'm running long integrations on a remote server, and I'm working in terminal in a tcsh shell. I'm looking to write ONLY the timing statistics to a file. For example: $time ls >timer.out writes both the files in my current directory & the timer statistics to the file timer.out. I only...

8. Red Hat

CPU Usage statistics Dump in a text file over a period of time

I am facing issue related to performance of one customized application running on RHEL 5.9. The application stalls for some unknown reason that I need to track. For that I require some tool or shell scripts that can monitor the CPU usage statistics (what we get in TOP or in more detail by other...

9. UNIX for Advanced & Expert Users

Need optimized awk/perl/shell to give the statistics for the Large delimited file

I have a file size is around 24 G with 14 columns, delimiter with "|" My requirement- can anyone provide me the fastest and best to get the below results Number of records of the file First column and second Column- Unique counts Thanks for your time Karti ------ Post updated at...

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)