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Blue-ray

Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer electronics, personal computer and media manufacturers…..

Check more on http://www.blu-ray.com/

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What is Cron?

Cron is very simply a Linux module that allows you to run commands at predetermined times or intervals. In Windows, it’s called Scheduled Tasks. The name Cron is in fact derived from the same word from which we get the word chronology, which means order of time.

The easiest way to use crontab is via the crontab command.

# crontab –e

This command ‘edits’ the crontab. Upon employing this command, you will be able to enter the commands that you wish to run. My version of Linux uses the text editor vi. The syntax of this file is very important – if you get it wrong, your crontab will not function properly.

The syntax of the file should be as follows:

minutes hours day_of_month month day_of_week command

All the variables, with the exception of the command itself, are numerical constants. In addition to an asterisk (*), which is a wildcard that allows any value, the ranges permitted for each field are as follows:

Minutes: 0-59
Hours: 0-23
Day_of_month: 1-31
Month: 1-12
Weekday: 0-6

We can also include multiple values for each entry, simply by separating each value with a comma.

So, if we want to run a script every Tuesday morning at 8:15 AM, our mycronjob file will contain the following content on a single line:

15 8 * * 2 /path/to/scriptname

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To count no. of files and folders in Linux

ls -l grep . -wc

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Javascript code to Check Special Characters


function chkSpecialChar(formelement,text)
{
var msg='true';
var a=formelement.value;
var b=a.length;
var cha='`~!@#$%^&()+-[]{}/;:,<>.?';
var ch=cha.length;
var i,j;
for(i=0;i<ch;i++)
{
var ch1=cha.substring(i,i+1);
for(j=0;j<b;j++)
{
var a1=a.substring(j,j+1);
if(a1==ch1)
{
msg='Special Characters like ' +cha+ 'are not allowed in '+text;
alert(msg);
formelement.focus();
return false;
}
}
}
if (msg=='true')
{
return true;
}
}