MS-Dos Programing..

  ♥ Logging on to a Drive

When you type in MS-DOS commands, your drive letter is shown on the command line. You can log on the A: drive (have the A: drive as your prompt) or on to any valid drive by just typing in the drive letter followed by a colon and then pressing Enter. When you log on to a drive, all your commands will be executed on that drive - unless you specify otherwise.

Here are the steps:

1. Put a floppy disk into your machine.

2. Open an MS-DOS window. You will be at the C:\> prompt (you may be inside a directory structure, but you will be on the C: drive)

3. At the prompt, type in A: and press Enter.

4. Do a DIR to prove you are now on a blank drive (a drive with no files on it).

♥ Making A Directory (using MKDIR or MD)

The way you make directories on a disk drive is to use the MKDIR command. The MKDIR command has a shortened form called MD and you can use either command interchangeably. For our examples, we will use MKDIR since that command is standard in at least one other operating system (Unix).

For this exercise, we will make a directory called FREEDOM on our floppy diskette. Which we will use in follow-on exercises. To make the directory, do the following:

1. Put your floppy disk into the computer.

2. Go to MS-DOS and log into the A: drive.

3. Using the MKDIR command, make a directory called FREEDOM. The syntax will be: MKDIR FREEDOM

(be sure you are on the A: drive when you use the command!)

♥  Changing Directories (using CHDIR or CD)

Directories are containers that are made to hold your files in a nice orderly way. To get to those directories and to see the files in them, you would use a combination of the CHDIR (or CD) commands and the DIR command. Do the following exercise to see how the CHDIR (or CD) command is used.

1. Put your floppy disk in the drive (be sure you have completed the previous MKDIR task)

2. Go to the MS-DOS prompt and log on to the A: drive.

3. Use the CHDIR command to enter the FREEDOM directory that you made previously. (CD FREEDOM)

4. Use the DIR command to see that there are no files in the directory. (only the . and .. files and those are for MS-DOS internal use).

5. Using the EDIT command, make two files. Call the first one AAA.TXT and the second one B.TXT.

6. Exit the EDIT program and do a DIR of the directory so you can see the files you just made.

7. Use the CHDIR command to get back to the root of the A: drive. ('CD \' is the command!)

        ☻ Important Shortcuts To Remember:

To change to the ROOT directory from any directory or subdirectory type:

CHDIR \ {ENTER}

To change to the parent directory of your current directory type:

CHDIR .. {ENTER}

  ♥ Adding Parameters to a command

A parameter is a letter typed after a command, that tells the command to carry out an extra task. These parameters are also called 'switches'.

For instance, a command that you've already used is the DIR command. The command with a parameter might look like this:

DIR /S /P

( The /S and the /P are the parameters. You can use either one.)

This Part	Tell MS-DOS to
DIR	Show the files and directories in the current directory ...
/S	.. and show all the files and directories below this directory (recurse )
/P	.. and show them one page at a time, waiting for the user to press 'Enter' between pages.

Most parameters are optional, however you will discover, over time, ones that you use frequently.

Go to the DOS prompt now and, with your diskette in drive A: do the following:

1. Log on to the A: drive

2. Do a DIR command

3. Do a DIR /S command and note the difference

    ♥ Copying Files (first look)

When you COPY a file, you make an exact duplicate of it. However, no two files in the same directory may have the same name. So you must either COPY the file to another directory, or copy it to another file name. We will look at copying files to another directory in a later lesson, but for this lesson, we want to make some copies of the files we created earlier on our floppy diskette and we want to keep all the files in the same directory called A:\FREEDOM. That means we will have to copy the files to different file names.

We want the following files in our A:\FREEDOM directory: A.DOC; AA.DOC; AAA.TXT; B.DOC; A.TXT; B.TXT. We will use them in the next lesson. Since it doesn't matter what's inside the files for our lesson, we will just copy one of the files we already made to the new filenames.

Do the following exercise:

1. Put your floppy disk in drive A:

2. Go to the MS-DOS prompt and log onto Drive A:

3. Go to the FREEDOM directory

4. In this directory, you already have AAA.TXT and B.TXT. Do the following COPY commands:

COPY AAA.TXT A.DOC

COPY AAA.TXT AA.DOC

COPY AAA.TXT B.DOC

COPY AAA.TXT A.TXT

5. Do a DIR to see the result

  ♥ Formatting a Diskette (review)

DANGER: BE SURE YOU ONLY FORMAT FLOPPIES! NEVER FORMAT YOUR C: DRIVE WHEN DOING THESE LESSONS ELSE YOU WILL LOSE EVERYTHING ON YOUR HARD DRIVE!!

You use the FORMAT command to format a diskette. We did that in our previous lesson.

Formatting a diskette you have previously used erases any data on the diskette, so only reformat a diskette if you are very sure you don't need any of the data on it.

1.      Type:

FORMAT A: {ENTER}

Note: To put the MS-DOS operating system files onto the diskette you are formatting, add the /S switch to the command

FORMAT A: /S {ENTER}

Putting the operating system on the diskette enables you to BOOT-UP the computer from the diskette. This disk is now known as a SYSTEM DISK.

NOTE THAT THIS COMMAND DOESN'T WORK ON WINDOWS 2000 or XP!!! The Windows 2000 or XP operating system is too big to fit on a diskette.

2. When this prompt appears on the screen.

Insert new diskette for drive A: and strike ENTER when ready

    insert the diskette you want to format into drive A:

    Press the {Carriage Return } or { ENTER } key.

3. When formatting is complete, and this prompt appears:

Format another (Y/N) ?

    Type Y (for yes) to format another diskette, N (for no) to exit from the FORMAT command

  ♥ Checking the Condition of a Disk

You use the CHKDSK command to:

• Check a disk to see how much space there is available, and how much is in use.

• Fix some disk errors, such as files that show a non-zero size but that really have no data in them

• Display information about the disk, including the total disk space, the number and size of files.

The command:

CHKDSK A: /F {ENTER}

Checks the disk in drive A: for errors and fixes any errors it can. If CHKDSK finds no errors it displays a report like this:

C:\>chkdsk A: /F

The type of the file system is FAT.

Volume Serial Number is 11EC-3150

Windows is verifying files and folders...

File and folder verification is complete.

Windows has checked the file system and found no problem.

1,457,664 bytes total disk space.

512 bytes in 1 folders.

3,072 bytes in 6 files.

1,454,080 bytes available on disk.

512 bytes in each allocation unit.

2,847 total allocation units on disk.

2,840 allocation units available on disk.

C:\>

If the CHKDSK command reports any errors on the disk, it displays a message such as:

xxx lost clusters found in xxx chains

and asks you whether you want to correct the errors.

Type Y (for yes) and then press the {ENTER} key.

NOTE:-This procedure can cause you to lose some of the information on your disk, however, not fixing the disk can cause you to lose even more!!