François Patte wrote:
...
1- Clipboard: it seems that there is a specific clipboard for Emacs
under Fedora/Gnome; I am unable to copy something from any other
application and paste it in emacs. It is always the last thing
copied/cut *in* emacs which is pasted in emacs whatever you could have
selected and copied in other windows (say: terminal, acroread...)
...
I am by no means an expert here, but I will try to explain what I know.
Right off the top, people see different behavior with emacs because (a)
the default behavior is unusual and awkward for new users, and
(therefore, b) emacs is often customized. I'm not sure what
configuration Fedora ships with anymore, I've fiddled with mine so much.
The first problem is that emacs is an old-style X application, and X
clipboard usage has evolved since emacs design was adopted. The status
quo for X on Linux now is that there are actually TWO clipboards, as you
experienced. One supports the old X usage, one supports the newer,
Windows-style "CUA" clipboard. Most newer GUI apps also support both,
but the interface hides the old-style, whereas in emacs, the old-style
clipboard is the "normal" emacs UI.
The old-style clipboard works like this: as soon as you select text with
the mouse in any X application, the text is available for pasting using
the middle mouse button. No keys to press at all, but it only holds one
item and if you select something else, the previous clipboard contents
are replaced. This selection/clipboard is named PRIMARY. It works
perfectly well for using the mouse to copy and paste text within emacs
as well.
Emacs also has it's own "clipboard" independent of X, which is called
the "kill-ring" it holds a bunch (configurable; mine is 60) of items.
Many editing operations in emacs automatically copy text to the
kill-ring; the top item can be retrieved with Ctrl-Y ("yank").
All the recent emacs installs that I've seen configure emacs to make the
top item in the kill-ring _equivalent to the X selection PRIMARY_. Thus,
whatever you can yank in emacs, you can also paste into any X app using
the middle mouse button, and whatever you select in another X
application, emacs will put that on the kill-ring.
The new-style X clipboard is the one that all newer apps connect to
Ctrl+C/X/V. This is named CLIPBOARD, and it also holds only one item,
but it is filled only when you issue a copy or cut request. The two
buffers, PRIMARY and CLIPBOARD, are completely independent and you can
have two different things "in the clipboard" at the same time: one
(PRIMARY) pasted by the middle mouse button, and one pasted by Ctrl+V
(CLIPBOARD).
Emacs can also use CLIPBOARD, but by default (AFAIK) there is no
interactive interface, i.e. Ctrl+C/X/V do not do have anything to do
with the clipboard in emacs. The emacs functions for accessing CLIPBOARD
are:
clipboard-yank ;; paste CLIPBOARD, like Ctrl+V
clipboard-kill-ring-save ;; copy the top kill-ring item to CLIPBOARD
clipboard-kill-region ;; kill text in region and copy to CLIPBOARD
These functions can be run (like any emacs function) by M-x
function-name; they may or may not be bound to some key (e.g. a function
key) or mouse button, depending on your configuration. If you run them
by name, emacs will tell you what altenate key bindings exist--watch the
minibuffer at the bottom.
There is a package called "cua.el" that provides more "normal" key
bindings for these, but I prefer to stick to the emacs standard
bindings. There is another configurable setting that automatically
copies items to CLIPBOARD as well as PRIMARY, but again, I prefer to
just keep them separate.
There you go, FMTYEWTK.
If you're just a glutton for punishment, you can read more about the X
clipboard here:
http://standards.freedesktop.org/clipboards-spec/clipboards-0.1.txt
and about emacs and the clipboard here:
http://www.jwz.org/doc/x-cut-and-paste.html
<Joe
