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🗂️ Mastering File Deletion in Uniface 10.4: A Developer's Guide to filedelete

#uniface #programming #filemanagement #development

Working with files in Uniface can sometimes feel like navigating through a maze, but the filedelete statement is one of those straightforward commands that does exactly what it says on the tin! 🎯

With the help of AI, I've put together this comprehensive guide based on the official Uniface documentation 10.4 to help you master file deletion operations in your Uniface applications.

🚀 What is filedelete?

The filedelete statement is your go-to command for removing files from the filesystem within Uniface applications. It's simple, efficient, and respects any file redirections defined in your assignment file.

Basic Syntax 

filedelete FilePath
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📝 Quick Example 

filedelete "sub1dir/test.txt"
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🔧 Parameters Deep Dive

Parameter Data Type Description
FilePath String File name with optional path. Can be located in ZIP archives. Must not end with directory separator.

📊 Return Values & Error Handling

Understanding what filedelete returns is crucial for robust error handling:

  • 0 ✅ - Success! Your file has been deleted
  • -13 ❌ - UIOSERR_OS_COMMAND error occurred

💡 Pro Tip: When you encounter error -13, set /pri=64 to display the exact error message in the message frame for easier debugging!

🎯 Key Features & Limitations

Path Specifications

You can specify the file path using various formats:

  • String literals
  • Field references (direct or indirect)
  • Variables
  • Functions that evaluate to strings

📏 Path Length Restrictions

Keep in mind that the total length of any path, filename, or directory name must not exceed 255 bytes.

🔀 Directory Separators

Uniface supports multiple directory separator formats:

  • Backward slash (\)
  • Forward slash (/)
  • Period with square brackets ([a.b])

These are automatically translated to platform-specific separators! 🌐

⚠️ When filedelete Fails

The operation will fail if the specified file:

  • Is not actually a file 📂
  • Does not exist 🔍
  • Is currently in use (locked) 🔒
  • Cannot be deleted due to insufficient permissions 🚫
  • Has invalid syntax 📝

🔥 Best Practices

  1. Always check return values: Don't assume file deletion succeeded
  2. Use proper error handling: Implement checks for the -13 error code
  3. Validate paths: Ensure your file paths are correctly formatted
  4. Consider permissions: Make sure your application has the necessary rights

🎪 Real-World Example 

; Delete a temporary file after processing
filedelete "temp/processing_data.tmp"

; Check if deletion was successful
if ($procerror = 0)
    ; Success - file deleted
    message "File deleted successfully! ✅"
else
    ; Handle error
    message "Failed to delete file. Error code: %%$procerror%%"
endif
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🎯 Conclusion

The filedelete statement is a powerful yet simple tool in your Uniface toolkit. By understanding its parameters, return values, and potential failure scenarios, you can implement robust file management in your applications.

Remember to always implement proper error handling and validate your file paths before attempting deletion operations! 🛡️

Happy coding! 🚀

Based on Uniface Documentation 10.4

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