# File System

These global variables provide information about file types, file handling, and file operations in the OSL environment.

## File Type Definitions

The `file_types` object contains definitions for various file types recognized by the system. Each entry includes:

* Icon definition (for visual representation)
* Description of the file type
* Associated applications that can open the file type

Here's a summary of some key file types defined in the system:

| File Extension                           | Description      | Associated Applications         |
| ---------------------------------------- | ---------------- | ------------------------------- |
| `.folder`                                | Directory/Folder | Files.osl                       |
| `.osl`                                   | Origin Script    | Process\_Opener.osl, Studio.osl |
| `.orsl`                                  | Origin Script    | Process\_Opener.osl, Studio.osl |
| `.txt`                                   | Plain Text       | Studio.osl                      |
| `.md`                                    | Markdown         | Studio.osl                      |
| `.json`                                  | JSON File        | Studio.osl                      |
| `.xml`                                   | Markup           | Studio.osl                      |
| `.js`                                    | Javascript       | Studio.osl                      |
| `.html`                                  | HTML File        | Studio.osl                      |
| `.css`                                   | CSS File         | Studio.osl                      |
| `.py`                                    | Python           | Studio.osl                      |
| `.png`, `.jpg`, `.jpeg`, `.webp`, `.bmp` | Image Files      | Previewer.osl                   |
| `.mp4`, `.webm`                          | Video Files      | Media\_Player.osl               |
| `.mp3`, `.wav`, `.flac`                  | Audio Files      | Media\_Player.osl               |

## File Constants and Special Values

| Variable   | Type   | Description                              |
| ---------- | ------ | ---------------------------------------- |
| `null`     | Null   | Special value representing null or empty |
| `newline`  | String | String representing a newline character  |
| `infinity` | Number | Special value representing infinity      |

## Examples

```javascript
// Check if a file extension is recognized
def isRecognizedFileType(filename) (
  local extension = filename.split(".").last()
  return file_types[extension] != null
)

// Get the description of a file type
def getFileTypeDescription(filename) (
  local extension = filename.split(".").last()
  local fileType = file_types[extension]
  
  if fileType (
    return fileType[2]
    // Return the description (second element)
  ) else (
    return "Unknown file type"
  )
)

// Get applications that can open a file
def getCompatibleApps(filename) (
  local extension = filename.split(".").last()
  local fileType = file_types[extension]
  
  if fileType and fileType[3] (
    return fileType[3]
    // Return the array of applications
  ) else (
    return []
  )
)

// Example usage
filename = "document.txt"

if isRecognizedFileType(filename) (
  log "File type: " ++ getFileTypeDescription(filename)
  
  apps = getCompatibleApps(filename)
  if apps.len > 0 (
    log "Can be opened with: " ++ apps.join(", ")
  ) else (
    log "No compatible applications found"
  )
)
```

## Notes

* The file types configuration is used by the system to determine how to display and handle different file types.
* New file types can be registered by applications by extending the `file_types` object.
* The icon definition uses a custom drawing syntax to define how the file type's icon should appear.
* Applications associated with file types are paths to OSL script files that can handle the specified file type.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://osl.mistium.com/global-variables/file-system.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.