Four years ago, I wrote an article about OpenOffice.org writer called "Fielding Questions, Part 2 - Cross References and User-Defined Fields." I regularly receive mail about it, but these days I have to preface each reply by explaining that the article is obsolete. Repeating the explanation gets old quickly, so I decided that an update is necessary.

You can use the dd and nc commands for exact disk mirroring from one server to another. The following commands send data from Server1 to Server2:

I've been using this grep invocation for years to trim comments out of config files. Comments are great but can get in your way if you just want to see the currently running configuration. I've found files hundreds of lines long which had fewer than ten active configuration lines, it's really hard to get an overview of what's going on when you have to wade through hundreds of lines of comments.

For some, databases can be pretty intimidating. I remember some of the convoluted code I wrote years ago in order to avoid having to learn how to access a database from my programs. But it's actually not that hard to access a database, even in C/C++.

One of the common questions we get here at linuxjournal.com is how we produce our videos. Shawn produced a howto video on some ways of doing it. The following describes how I capture my videos and also the script that I use to add the Linux Journal logo watermark to it.

Vim is one the more popular choices of text editors for Linux. For vim, there are a few non-default options that may be useful whether editing config files or writing scripts in your favorite language.

Some months back I developed some pyuno code for converting spreadsheets into CSV files from the command line. Pyuno being the Python interface to the OpenOffice runtime. One of the enhancement suggestions I got was to add the ability to extract all the sheets and/or a specific sheet rather than always extracting the first sheet. The following update to the code does just that.

Ghostscript gives you the power to combine files, convert files, and much more, all from the command line.

If you're coming fresh from Microsoft Excel, you might wonder where the Pivot tables are in OpenOffice.org Calc. The problem is, they're masquerading under the name of DataPilots. But, under any name, DataPilots are Calc's way of allowing you to quickly reorganize information in a range of cells so that you can gain a new insight into them.

Using the HISTCONTROL variable you can control how bash stores your command history. You can tell it to ignore duplicate commands and/or to ignore commands that have leading whitespace.

There are a number of ways to extract a range of pages from a PDF file: there are PDF related toolkits for doing it, or you can use Ghostscript directly.

If you need to move your Linux installation to a different hard drive or partition (and keep it working) and your distro uses grub this tech tip is what you need.

If you've used bash for a while you probably know that the commands you enter are saved in the file ~/.bash_history when you log out. Next time you log in, bash automatically loads these history commands from the saved file and you can then use the up and down arrow keys to browse your command history and find the command you want rather than re-entering it.

Do you have a linux server without a keyboard or monitor? Need to administer the server on-site but don't want to lug over a monitor and keyboard (or kvm)? Then setup the server to output the console to a serial port and use screen/minicom (Hyperterminal or putty in Windows) to console into the server over a serial cable.

To kick off the upcoming 4th of July celebrations we present the following bash script for your enjoyment.

To add a bit of color to your man pages install the most pager. For most DEB based distros:

In order to avoid this common mistake I often have my shell scripts prompt me for a yes or no answer before they proceed. The function described here is for doing that: asking a question and validating the answer.

As a consultant, I am often faced with an unfamiliar Linux system (usually RHEL). I always find it useful to understand which files that shipped with rpm packages have been modified, since it's usually a good indicator of what customizations have been performed on the system. To determine the modified files, I simply run:

On Debian based systems, or any that use Synaptic for package management, you can use Synaptic to help you setup multiple systems with the same software. On the first system select all the packages you want and then under the File menu use Save Markings or Save Markings as to save your selections to a file.

To see the interrupts occurring on your system, run the command: