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Readline Killing Commands
-------------------------

   "Killing" text means to delete the text from the line, but to save
it away for later use, usually by "yanking" (re-inserting) it back into
the line.  If the description for a command says that it `kills' text,
then you can be sure that you can get the text back in a different (or
the same) place later.

   When you use a kill command, the text is saved in a "kill-ring".
Any number of consecutive kills save all of the killed text together, so
that when you yank it back, you get it all.  The kill ring is not line
specific; the text that you killed on a previously typed line is
available to be yanked back later, when you are typing another line.

   Here is the list of commands for killing text.

<C-k>
     Kill the text from the current cursor position to the end of the
     line.

<M-d>
     Kill from the cursor to the end of the current word, or if between
     words, to the end of the next word.

<M-DEL>
     Kill from the cursor the start of the previous word, or if between
     words, to the start of the previous word.

<C-w>
     Kill from the cursor to the previous whitespace.  This is
     different than <M-DEL> because the word boundaries differ.

   And, here is how to "yank" the text back into the line.  Yanking
means to copy the most-recently-killed text from the kill buffer.

<C-y>
     Yank the most recently killed text back into the buffer at the
     cursor.

<M-y>
     Rotate the kill-ring, and yank the new top.  You can only do this
     if the prior command is <C-y> or <M-y>.