Century's diskettes were formatted in the following ways:

• 3.5" disks are written with a block of 18 and a size of 720
• 5.25" disks are written with a block of 10 and a size of 2400
• Cartridge tapes are usually written with a block of 20.

On SCO UNIX and XENIX, you can use the tar command to find out what your devices are configured as:

$ tar
Usage: tar -{txruc}[0-9vfbkelmnpwAF] [tapefile] [blocksize] [tapesize] files...

Key	Device	Block	Size	Tape
0	/dev/rfd048ds9	18	720	No
1	/dev/rfd148ds9	18	720	No
2	/dev/rfd096ds15	10	2400	No
3	/dev/rfd196ds15	10	2400	No
4	/dev/rfd096ds9	18	1440	No
5	/dev/rfd196ds9	18	1400	No
6	/dev/rfd0135ds18	18	2880	No
7	/dev/rfd1135ds18	18	2880	No
8	/dev/rct0	20	0	Yes
9	/dev/rctmini	20	0	Yes

The tar devices in the book are for a standard installation. The following test can be used to determine what device name is needed for the tar command:

# for x in `ls /dev/rfd*`

NOTE: Use the tic character, not the single quote mark

> do
> echo "device: $x"
> tar xvf$x
> done
#

The "rfd" in the for command will need to be changed to the proper device name for the operating system.

• INTERACTIVE UNIX SYS V/386: /dev/rdsk/*
• SCO UNIX/XENIX: /dev/rfd*
• SUN MICROSYSTEMS: /dev/rst*