For several weeks, I’ve been trying out PCLinuxOS, one of the new, free Linux distributions. You can download the ISO (image file) of the PCLinuxOS "live CD" from www.pclinuxos.com and try it yourself. Use the Burn An Image function in your CD-burning software (such as Nero) to turn the ISO file into a bootable CD that will let you run PCLinuxOS directly from the CD. If you like it, you can install it from the CD, too.
I answered a question this week that brought back to mind some of the reasons that Linux is like Windows.
In this particular case, the writer had installed PCLinuxOS on his home computer (dual booting with Windows XP) but had run into a hardware issue.
Most of his hardware was recognized and handled automatically. However he had a Zip drive that wasn’t recognized.
What’s a Zip drive? Before the days of cheap flash drives, before the days of CD drives, and before the days of cheap CD burners and cheap CDs, one of the solutions was basically a large floppy drive that held 100 MB (later 250 MB).
This new Linux user had solved the problem of getting PCLinuxOS to recognize and handle his Zip drive — but any time he rebooted, he had to type several commands to get the drive recognized.
The solution was a feature of PCLinuxOS that’s available in most Linux distributions.
Just as the DOS and earlier Windows versions had the autoexec.bat file into which we could insert commands, Linux has a similar file.
In distributions based on RedHat’s RPM package manager, including PCLinuxOS, the file is /etc/rc.d/rc.local
The last file executed by the startup routine is the rc.local file. You can see the sequence of files by typing in a terminal window (a command window):
The ‘ls’ command means list the directory. The /etc directory is where OS configuration files are located and many other programs set up subdirectories for their configuration files there (makes updates easier). The /etc/rc.d directory has multiple subdirectories for different types of startups — rc3.d is the directory of commands to start Linux in with its graphic startup; rc6.d has the shutdown scripts.
The files in rcX.d are all symbolic links to the real version of the file – and they are named SxxFILENAME, where S=start, xx=order. There are also KxxFILENAME, where K=kill (stop).
Since the rc.local file is a file of commands, you do not want to use an editor that embeds formatting information – you need to use a plain text editor. Use the graphical editor vi (click on the PC button, then Applications, Editors, vi), which will start the editor gvim (graphical VI iMproved).
Hope this helped — probably confusing, but it brushed across several important concepts. Bottom line, you can put the command into the rc.local file, at which point it will be executed as part of the boot process.