Linux Devices - Part V

They’re the core of your Linux system, those enigmatic device files. We’re continuing on with our look into these core components today with a peek into the world of parallel device files.

/pda: Nope. This isn’t the directory to your Palm or Visor. That’s generally a symbolic link from /dev/ttySx to /dev/pilot or /dev/visor. /dev/pda is actually a nearly outdated file creating communication with a parallel port IDE disk. Like 5 1/2 ” floppies and 8-track tapes, you just don’t see too many of these anymore.

/pcd0: Another rare device - a parallel port CD-ROM. Need I say more?

/pt0: This parallel device is a bit more common - a parallel port tape backup drive. This, in fact, is the first [p]arallel [t]ape device, as denoted by the 0. Subsequent devices are numbered accordingly.

/parport0: This is the device file for a raw parallel port. In other words, a parport-connected device doesn’t require drivers to operate, as do most other devices. That’s what makes it raw.

With the advent of USB, we’re seeing fewer and fewer parallel port devices. Consequently, the device files that cover this class of hardware are beginning to show their age a bit. However, if you should happen across a 5-gig parallel port hard drive on eBay at a price you can’t resist, at least you’ll know where in the device dirctory to find it.

Tomorrow, we’ll wrap up the series on Linux device files with two more strange and mysterious files - random and zero.