When you're in the incremental reverse search mode, you can get into a situation where it appears nothing is happening and that you're stuck. This happens when you've typed a string that doesn't appear in your history and you hit Ctrl-R. For example:
altsql> laksjd^R
i-search qr(laksjd): laksjd
At this point, any key you type will add to the incremental search but will not be registered on the screen. Further, Ctrl-C and Ctrl-D don't work. The only key you can type to escape this is Del, which will backspace from the end of the buffer. Once the buffer once again reflects items in your history, you can then Ctrl-C or Ctrl-D.
When you're in the incremental reverse search mode, you can get into a situation where it appears nothing is happening and that you're stuck. This happens when you've typed a string that doesn't appear in your history and you hit Ctrl-R. For example:
At this point, any key you type will add to the incremental search but will not be registered on the screen. Further, Ctrl-C and Ctrl-D don't work. The only key you can type to escape this is Del, which will backspace from the end of the buffer. Once the buffer once again reflects items in your history, you can then Ctrl-C or Ctrl-D.