Overview of File Handlers

Documentation / Contents - File Handlers

• Overview of File Handlers
  • The Pair
  • What a File Type Is
• Opening a File
  • What Happens When You Open Something
  • Opening With a Particular Tool
• The File Handlers Panel
  • The File Type List
  • The Opens With List
  • The Detail Line
  • The Buttons
• Choosing a Handler
  • Auto-Pick Best
  • Try It
  • Opening Nothing
• Icons
  • The Available Icons List
  • Set Icon
• Creating New Files
• The Canonical Panel
• Where the Settings Live
  • The Master List
  • The Rule Files
  • The Ranking Tables
• From the Command Line
• Copyright Information

File Handlers

When you open a file from the File Manager, something has to decide which application to run. That decision is what these two programs are about: what kind of file it is, and which application opens that kind.

The Pair

Blueprint splits doing from configuring, the same way the window manager and its preferences panel are split.

cyopen          does it: type, then handler
cyopen-prefs    configures it: the panel

You rarely run cyopen yourself. The File Manager runs it when you open an icon; it is also useful from a shell, where it is a one-word "open this sensibly".

In This Book

• Opening a File
• The File Handlers Panel
• Choosing a Handler
• Icons
• Creating New Files
• The Canonical Panel
• Where the Settings Live
• From the Command Line

What a File Type Is

A type is a name for a kind of file, such as Directory, PlainText, Image, Audio, Video, PDF, PostScript, Html or Source. A file is matched to a type by rules: mostly by the file's suffix, sometimes by looking at its contents.

Each type carries two things:

an icon      what the file looks like in the File Manager
a handler    the command that opens it

Setting either one is what the File Handlers panel is for.

There is one mechanism here and only one. Blueprint does not read the freedesktop .desktop files and has no second, parallel registry of associations. The rule files are it.