Saving Files Via Drag-and-Drop: The Direct Save Protocol for the X Window System
Technical details
Current version: 0
Unless otherwise noted, all constants mentioned below are the string names of X atoms, capitalized as shown. This avoids the need for hard-coded values, which would require a global registry.
Atoms and Properties
XdndDirectSave
This is both a window property and a data type. In both cases, the full name of the atom is XdndDirectSave0. The version number is included in the name to allow new versions of the protocol in the future. All applications are required to support all previous versions of this protocol. A file manager should search the list of available data types starting with the latest version of XdndDirectSave that it supports and use the latest version that it finds. This is equivalent to the way the XDND protocol works. For direct save, the version number is part of the atom name instead of being stored in a window property because the latter method would require more network traffic.
The window property must be of type text/plain, including the charset attribute, if necessary. This allows file names to contain any character that the file system can handle. File managers that cannot handle the character set can refuse the drop. Applications that cannot handle the character set returned by the file manager can treat this as an error and return E. (Refer to step 2 of the walk-through.) If the charset attribute is not set, it is assumed to be ISO-8859-1.
XdndActionDirectSave
This is the action that is sent to the target.
application/octet-stream
This data type is reserved to provide the data in the exact format that the program would write to disk.