asked on

file

i have a filr test.txt

cat test.txt
3

it only contains a integer value....i want to increment the value

is it possible to do it whithout opening the file, then reading the current value, then open in write mode.

is it possible to do in just 1 step

Rahul

ASKER CERTIFIED SOLUTION

ozo

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shahrahulb

ASKER

hahaha that is the problem i discussed in my previous question
# my $d = CounterFile->new("$CONFIG::DATA/$file");
# $d->inc;

when multiplt users hit the url at same time, i get the error
Software error:
Can't flock: No record locks available at /v/test.cgi line 40 and line 40 contains my $d = CounterFile->new("$CONFIG::DATA/$file");

so i m creating my own counter logic

if u have any alternative solution i m open

ozo

Maybe you can try appending a line to the file to increment, and counting the number of lines to read the counter.

ZiaTioN

You could use the filename itself as the integer value and increment that. However if this were the case the filename would change everytime and therefore you would need to perform a readdir every time and look for your text file and then increment and recreate the new file by opeing it anyway and then closing it and then remove the old file.

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#!/usr/bin/perl -w

use strict;

opendir (DIR, '.') ||
die "Unable to read current directory: ($!)\n";
my @files = grep {/\d+\.txt/} readdir (DIR);
closedir(DIR);

die "Multiple files found!\n" unless (scalar @files < 2);

my $newfile = $files[0] || 0;
$newfile =~ s/\.txt//;
$newfile++;
$newfile .= '.txt';
open(NEW, ">", $newfile) ||
die "Unable to create $newfile: ($!)\n";
close(NEW);
unlink($files[0]) if ($files[0]);
_____________________________

ozo

Is there a database server accessible from all the machines that want to use the common counter?

brado1234

You do not need perl to increment the number in the file. You can simply do it through the command line.. or a simple shell script....

cat test.txt | awk '{print $1+1}' > test.txt

This will take the number inside of the file "test.txt" and will increment it, and then write it back to the file "test.txt".

Is this what your looking for???

brado1234