In this section, we will cover the fundamental file operations in OpenVMS. Understanding how to manage files is crucial for any OpenVMS user, as it forms the basis for most system interactions. We will explore how to create, read, write, copy, move, and delete files using DCL (Digital Command Language).

1. File Creation: How to create new files.
2. File Reading: How to read the contents of a file.
3. File Writing: How to write data to a file.
4. File Copying: How to duplicate files.
5. File Moving: How to move files from one location to another.
6. File Deletion: How to delete files.
7. File Attributes: Understanding and modifying file attributes.

To create a new file in OpenVMS, you can use the CREATE command. This command opens a new file for writing.

Explanation:

• $ CREATE MYFILE.TXT: This command creates a new file named MYFILE.TXT.
• After entering the command, you can type the content of the file.
• Press Ctrl+Z to save the file and exit the editor.

To read the contents of a file, you can use the TYPE command.

Explanation:

• $ TYPE MYFILE.TXT: This command displays the contents of MYFILE.TXT on the screen.

To write data to an existing file, you can use the APPEND command or the OPEN/WRITE and WRITE commands in a script.

Explanation:

• $ APPEND "Additional line of text." MYFILE.TXT: This command appends the text "Additional line of text." to MYFILE.TXT.

To copy a file, use the COPY command.

Explanation:

• $ COPY MYFILE.TXT MYFILE_COPY.TXT: This command creates a copy of MYFILE.TXT named MYFILE_COPY.TXT.

To move a file, use the RENAME command.

Explanation:

• $ RENAME MYFILE.TXT NEWFILE.TXT: This command renames MYFILE.TXT to NEWFILE.TXT, effectively moving it.

To delete a file, use the DELETE command.

Explanation:

• $ DELETE MYFILE.TXT;*: This command deletes all versions of MYFILE.TXT.

File attributes provide metadata about the file, such as its size, creation date, and permissions. You can view and modify these attributes using the DIR and SET FILE commands.

Explanation:

• $ DIR/FULL MYFILE.TXT: This command displays detailed information about MYFILE.TXT.

Explanation:

• $ SET FILE/PROTECTION=(S:RWED,O:RWED,G:RE,W:RE) MYFILE.TXT: This command sets the file protection attributes for MYFILE.TXT, allowing different levels of access for system, owner, group, and world.

1. Create a new file named EXERCISE1.TXT and write "Hello, OpenVMS!" into it.
2. Read the contents of EXERCISE1.TXT.

Solution:

1. Copy EXERCISE1.TXT to EXERCISE1_COPY.TXT.
2. Append "This is a copy." to EXERCISE1_COPY.TXT.
3. Read the contents of EXERCISE1_COPY.TXT.

Solution:

1. Delete EXERCISE1_COPY.TXT.

Solution:

• Forgetting to Save: Always remember to press Ctrl+Z to save and exit when creating or editing a file.
• Incorrect File Names: Ensure you use the correct file names and extensions to avoid errors.
• File Protection: Be cautious when setting file protection attributes to avoid unauthorized access.

In this section, we covered the essential file operations in OpenVMS, including creating, reading, writing, copying, moving, and deleting files. We also explored how to view and modify file attributes. These operations form the foundation of file management in OpenVMS, and mastering them is crucial for effective system use. In the next section, we will delve into directory management, which will build on the concepts learned here.