I have admitted several times in this column that I can be absentminded and careless. At least I meant to. Regardless, this tendency got me into an annoying situation recently. I made several changes to my system at once. I swapped my network card, rebuilt the kernel to try out different USB drivers, and made a few other changes. But I forgot to make changes to the file /etc/modules, which would tell the system to load the appropriate modules for my USB driver, keyboard, mouse, and new network card.

When I rebooted the system, I couldn't operate the machine. Linux ignored my USB keyboard and mouse and I couldn't contact the computer over the network using ssh (secure shell) because it didn't load support for the new network card. (See Resources for a link.)

There are several very simple ways of dealing with this situation. For example, I could hunt down a keyboard with a PS/2 connector and plug it in, or I could reboot the system with a previous kernel version. Being lazy by nature, I didn't want to look for a keyboard. Being impatient by nature, I didn't want to wait for the system to reboot. I especially dislike reboots. My system seems to take forever to initialize the IDE drives and controllers, the Intel Ethernet Express Pro management BIOS, and the Adaptec SCSI BIOS at boot time.

Fortunately, I anticipated such an event and left myself one more option. I set up Linux so that I could access it using my Palm Pilot as a VT100 terminal connected to the serial port. I logged in via the Palm Pilot, loaded the USB driver and modules for my keyboard, and was back in business in a wink.

There are other ways a Palm Pilot terminal can help you work or get you out of a jam. I imagine it could really come in handy as a debugging tool, especially if you're building a full-screen graphical application. You can redirect various types of error or debugging messages to your Palm terminal while you develop your application. Your Palm instantly takes on the role of a second monitor.

Here's how to set up your Linux system to work that way: First, make sure your Linux kernel supports the serial ports on your machine, and also supports the console on the serial port. Your kernel may already support these options, but if not, you can build a new kernel yourself. If you use make menuconfig as your kernel configuration tool, select the Character Devices section and mark these two options in the screen that comes up:

<*> Standard/generic (8250/16550 and compatible UARTs) serial support
  [*]  Support for console on serial port

You also need the program getty

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