Hi,
May I know how to check for empty file in Perl.
Iam missing something, somewhere.
#!/usr/bin/perl
my $open_dir = '/path/';
my $file;
my $ma = "abc_.*.\.psv\$"
opendir(VAR, $open_dir) or die "Can't open $oepn_dir: $!\n";
while( defined ($file = readdir VAR) ) #read all... (1 Reply)
Hi Masters.....
I have problem !!!
I need to check number of records in a file and if it is zero or file is empty i need to do some task.
if ; then
echo "File s empty"
else
echo "Not empty"
fi
so how to check this condition.
I used wc -l < filename.txt => 1 for zero records
same result... (1 Reply)
Hi All,
I am new to unix worldd .
I need to check a file1 if its empty or not.
If its empty then return a non zero value say 99
could you pls let me know the perl script for this. (2 Replies)
How do I check if a file is empty in a sh script
I want to test in my shell script if the output file is empty and if it is do one thing and if it isnt empty do another?
any ideas? (8 Replies)
I am running a C shell script. I have an output file from a previous step and I need to run "something" in the next step to check if the file is empty. If the file is empty, then the job script should finish EOJ. If the file is not empty then the job script should abend.
Please help
Thanks. (4 Replies)
Hello,
I want to make a script which says if a text file is empty or not.
I tried two ways of making it, but I have problems with both of them.
Now I think that the better way is the ls -s solution (considering that an empty text file has a 0 weight, because "cat file.txt" fails when file is... (4 Replies)
Hello again!
I have some trouble with scripting in bash.
In the following script I read from a folder with the files
line0_Ux.xy
line1_Ux.xy
line2_Ux.xy
.
.
.
Some of the files are empty. For those I would like to print a "0" in list.
I think the problem with the code is that... (4 Replies)
Hi gurus ,
I have two files and i want to perform different action based on the condition if both or either is empty
If
then
Do something
elif
then
do something
elif
then
do something
else
do something
fi
I have tried the below bt its not... (4 Replies)
Hi,
I am using KSH.
I am trying to check if the output file is empty or not.
I tried with ] but what i see is my file is empty but still manages to have a size of 1 instead of 0.
But my file doesnot have anything its empty.
I am not sure how to check this.
can any one help? (10 Replies)
Hi All,
I need to check a file whether it exists and also whether it is empty or not. I have a code for this but it is not working as per my requirement. Can anyone pls suggest me on this.
function funcFLSanityCheck
{
if
then
echo "${varFLSentFileListPath}/${varFLSentFileName}... (7 Replies)
Discussion started by: Arun1992
7 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)