PING

Ping is a Unix utility that sends ICMP ECHO to the server ( destination machine ) from the client ( originating machine ). It takes its name from a submarine sonar search – you send a short sound burst and listen for an echo – a ping – coming back. There is a myth that Ping is actually an acronym for the words ‘Packet INternet Groper’, but there is no proven evidence to support the statement.

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Working on a *nix system is no piece of cake. Especially when you are used to Graphic interface of ‘windows’. The world where mouse is the king.

Here is  a list of most used / most discussed / most important  *nix commands. Mastering this will surely get your confidence level high in the black background and white characters’ world !!

My experience says that for starters in UNiX / LiNuX , these commands are enough to get you in smoothly !   (more…)

AWK is a general purpose programming language that is designed for processing text-based data, either in files or data streams, and was created at Bell Labs in the 1970s

I noticed that Erik Wendelin wrote an article “awk is a beautiful tool.” In this article he said that it was best to introduce Awk with practical examples. I totally agree with Erik.

Eric Pement’s Awk one-liner collection consists of five sections:

• 1. File spacing,
• 2. Numbering and calculations,
• 3. Text conversion and substitution,
• 4. Selective printing of certain lines,
• 5. Selective deleting of certain lines.

The first part of the article will explain the first two sections: “File spacing” and “Numbering and calculations.” The second part will explain “Text conversion and substitution”, and the last part “Selective printing/deleting of certain lines.” (more…)

Ever wonder how to scroll upwards in mysl resultset ?

What if your terminal doesn’t allow scrollback or the scrollback buffer is somehow set to sreen lines ?

How to use MORE or LESS unix commands in mysql which would allow to scroll using ‘return’ or ’spacebar’

Follow the steps given below:

1. mysql –page uuser -p  [Invoke mysql using the --page command]
2. mysql> pager less          [set the pager to use less]
3. mysql> select * from table_name  [run your query]

This also  works under the unix ’screen’ terminal emulation

A fork bomb works by creating a large number of processes very quickly in order to saturate the available space in the list of processes kept by the computer’s operating system. If the process table becomes saturated, no new programs may be started until another terminates.

WikiPage : http://en.wikipedia.org/wiki/Fork_bomb

while(1)
pcntl_fork();

Note: Process Control support in PHP is not enabled by default. You have to compile the CGI or CLI version of PHP with –enable-pcntl configuration option when compiling PHP to enable Process Control support.
Currently, this module will not function on non-Unix platforms (Windows).