Returns the primary selection.
capi
selection self &optional format => result
| self⇩ | 
A displayed CAPI pane or interface. | 
| format⇩ | 
A keyword. | 
| result | 
A string, an image, a Lisp object, or  nil. | 
The function selection returns the contents of the primary selection as a string, or nil if there is no selection.
format controls what kind of object is read. The following values of format are recognized:
| :string | 
The object is a string. This is the default value. | 
| :image | 
The object is of type image, converted from whatever format the platform supports. | 
| :value | 
The object is the Lisp value. | 
When format is :image, the image returned by selection is associated with self, so you can free it explicitly with free-image or it will be freed automatically when the pane is destroyed.
On Microsoft Windows there is no notion of selection, so this mechanism is internal to Lisp.
Note that X applications may or may not use the primary selection for their paste operations. For instance, Emacs is configurable by the variable interprogram-paste-function.
clipboard
free-image
image
selection-empty
set-selection
18.6 Clipboard
CAPI User Guide and Reference Manual (Unix version) - 01 Dec 2021 19:32:42