DOS in more depth

Running a Program

If you're on your own and nothing seems to happen automatically, you need to start a program yourself.  Here's how:

First, you need to know the program's name.  Then you type that name at the command prompt.

For example, WordPerfect is named WP.  To run WordPerfect, you type WP at the DOS prompt and then Enter:

C> WP

Resetting  

Resetting your computer is a way to turn it off and on again without having to actually do that (and it's healthier for the PC than kicking the power cord out of the wall, despite the full feeling that gives you).  When you reset, you're restarting the computer while it's on.

There are two ways to reset:  If your computer has switch, you can push it.  Otherwise, you can press and hold the Ctrl, Alt and Delete keys at the same time.  Release the keys.  This procedure is known as the three-finger reset, or Ctrl-Alt-Delete ("control-alt-delete").

The reason for leaving your computer on

There are lots of interesting reasons why you should leave a computer on all the time.  One is that the initial process of turning a computer on is a tremendous jolt to the system.  It's often said that you subtract one day from the computer's life for each time you switch the system off and then on.  But who knows?

The truth is, leaving the computer on all the time keeps the temperature inside the box even.  When you turn the system off, the electrical components cool.  Turn the PC on again, and the components heat right back up.  (The system's fan will keep them from getting too hot)  It's that temperature change from turning the system off and on that causes the damage.  After a time, the solder joints become brittle from the changing temperature and they'll crack.  That's when the real problems occur.  By leaving your PC on all the time - or just by minimizing the times you turn it off and then on - you can prolong it's life.

An opposing school of thought claims that although the preceding is true, leaving the computer on all the time wears down the bearings in your hard drive and causes the cooling fan to poop out prematurely.

Now the question arises:  When should you reset?  Obviously, at any time you're panicked.  Personally, I only reset if the keyboard is totally locked up and the program appears to have gone to the mall for some Mrs. Field's cookies and a soda.  (Sometimes Ctrl-Alt-Delete doesn't work in these situations, so if you don't have a big reset button, you have to turn the computer off, and wait, and then turn it on again.)

The only time you really need to reset is just to "start over".  For example, I was experimenting with a program that made my keyboard click every time I pressed a key.  There was no obvious way to turn off this annoying pestilence, so I reset.

• As with turning a computer off, you shouldn't reset while the disk drive light is on or while you are in an application (except when the program has flown south).  Above all, do not reset to quit an application.  Always quit properly to DOS before you reset or turn off the computer.
• Remember to remove any floppy disks from drive A before resetting.  If you leave a disk in, the computer will try to start itself from that disk.

The DIR Command

The most popular DOS command is DIR, which displays on the screen a list of files on disk.  This is how you can find which programs and data files are located on a disk.  DIR is especially helpful if you're missing something; it will help you locate that document or spreadsheet you were recently working on.

To see a list of files, type DIR at the DOS prompt and press Enter.   

C> DIR

If the list is too long, you can type the following DIR command:

C> DIR /P

The /P makes the listing pause after each screenful of files.  (Remember, "Wait for the P")

To see a list of filenames only, type the following DIR command:

C> DIR /W

The /W means wide, and it gives you a five-column name-only list.

If you want to see the on a floppy drive, follow the DIR command with the letter of the floppy drive:

C> DIR A:

Here, DIR is followed by A; indicating that it should list files on any disk in that drive.  (There should be a disk in the drive before you use that command.)  If you want to find out which files are on drive B, for example, substitute B: for A:.

Changing Drives

The computer can only pay attention to one disk at a time.  To switch its attention from one drive to another, type that drive's letter followed by a colon.  Press Enter to log to that drive.  (Whichever drive the computer is currently using is referred to as the logged drive; using equals logged in computerspeak).

For example, to change from drive A to drive C, type

A>  C:

To change from drive C to drive B, type

B>  B:

A colon always follows a drive letter in DOS.

• Drive A is always the first floppy drive, drive C is always the first hard drive.  A second floppy drive is drive B.  Any additional drives in the system are lettered from D on up through Z.

Using the CD command

To change to another directory on a disk, you use the CD command followed by the name of the directory:

C>  CD \WORD\DATA

In this example, the CD command changes directories to the \WORD|DATA subdirectory. Note the space between CD and the directory's pathname.

To change to the root directory or any disk use the following command:

D>  CD \