File Structure in DOS

 

File Structure in DOS

The file structure in DOS consists of the following key elements:

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1. Root Directory

• The root directory is the topmost level in the DOS file structure.
• It is represented by a drive letter followed by a colon (C:\, D:\, etc.).
• All other directories and files are organized under the root directory.

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2. Directories and Subdirectories

• Directories are folders used to organize files into manageable groups.
• Subdirectories are directories within other directories, forming a hierarchical structure.
• Example:

makefile

C:\Documents

C:\Documents\Projects

C:\Documents\Photos

• The backslash (\) is used to separate directories and subdirectories.

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3. Files

• Files are the basic storage units in DOS, containing data or programs.
• A file in DOS has two main parts:
• Filename: Up to 8 characters.
• Extension: Up to 3 characters, separated by a dot (.), used to identify the file type (e.g., .TXT, .EXE, .BAT).
• Example: MYFILE.TXT

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4. File Naming Conventions

• DOS follows the 8.3 filename format, meaning filenames can have:
• Up to 8 characters in the name.
• Up to 3 characters in the extension.
• Rules:
• Filenames cannot contain spaces or special characters like /, \, :, *, ?, ", <, >, |.
• Filenames are case-insensitive (e.g., MYFILE.TXT is the same as myfile.txt).

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5. Pathnames

• A pathname specifies the location of a file or directory in the file structure.
• It can be:
• Absolute Path: Specifies the complete path from the root directory.
• Example: C:\Documents\Projects\Report.doc
• Relative Path: Specifies the path relative to the current directory.
• Example: Projects\Report.doc

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6. Special DOS Directories

• Current Directory: The directory you are currently working in. Use the CD command to change it.
• Parent Directory: The directory above the current directory. Represented by ...
• Root Directory: The topmost directory. Represented by \.

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7. Common DOS Commands for File Structure

• DIR: Displays the list of files and directories in the current directory.
• Example: DIR C:\
• CD (Change Directory): Changes the current directory.
• Example: CD Documents
• MD (Make Directory): Creates a new directory.
• Example: MD Projects
• RD (Remove Directory): Deletes a directory.
• Example: RD Projects
• COPY: Copies files.
• Example: COPY source.txt destination.txt
• DEL: Deletes files.
• Example: DEL myfile.txt

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Hierarchy Example

C:\

│

├── Documents

│   ├── Projects

│   │   ├── Report.doc

│   │   └── Budget.xlsx

│   └── Photos

│       └── Vacation.jpg

├── Programs

│   ├── App.exe

│   └── Utility.bat

└── Autoexec.bat

In this example:

• The root directory is C:\.
• Documents and Programs are subdirectories of the root.
• Projects and Photos are subdirectories of Documents.