Question

How can change this behaviour:

1. C-s — start incremental search
2. type word — misprint the last character
3. Backspace — Oops! incremental search disappears, and I actually delete 1 character from the buffer.

to that one:

1. C-s — start incremental search
2. word — misprint the last character
3. Backspace — delete the last d character
4. type k — work — correct, and continue the search

I run Emacs in text terminal via SSH in PuTTY.

Operating system version: 2.6.16.60-0.58.1.1882.3.PTF.638363-smp #1 SMP Wed Dec 2 12:27:56 UTC 2009 x86_64 x86_64 x86_64 GNU/Linux

Emacs version: GNU Emacs 23.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.14.6) of 2010-07-16

With the -q option, Backspace sent by PuTTY is just C-h, and it acts like C-h, but in my .emacsfile I it bind to delete-backward-char:

(global-set-key [(control h)] 'delete-backward-char)

Answer 1

What you should do is configure PuTTY to send C-? (byte 127) for Backspace instead of C-h (byte 8). This is the setting that works best in most circumstances. See the
PuTTY manual.

If you changed the PuTTY setting to send C-h because some other application didn’t work, check that your terminal settings are correct on the server. The setting is often correctly autodetected, but sometimes you may need to add stty erase '^?' to your shell configuration file (.bashrc or similar) on the server.

If you really absolutely have to have Backspace send C-h, then globally rebinding C-h isn’t sufficient. Instead, add (normal-erase-is-backspace-mode 1) to your .emacs. See the Emacs manual.