ESC 4 causes part of file to be missing from buffer

ESC 4 causes part of file to be missing from buffer

[Joe Fineman]

I am using Emacs 21.3.1 under Windows.

When I visit a file that contains the sequence ESC 4, I find that the
resulting buffer is missing all the text from there up till the next
ESC (or till the end, if there is no such ESC).  I have determined
that the text is not merely missing from the display, but from the
buffer itself.  On the other hand, the file itself seems not to be
corrupted: if I view it using cat in the Cygwin shell, it is still
all there.  The buffer is not marked as modified.

Is this a feature that I can turn off, or is it a bug?
-- 
---  Joe Fineman    joe_f@verizon.net

||:  Blessed are they who expect nothing, for surely they shall  :||
||:  not be disappointed.                                        :||

Re: ESC 4 causes part of file to be missing from buffer

[Kevin Rodgers]

Joe Fineman wrote:
 > I am using Emacs 21.3.1 under Windows.
 >
 > When I visit a file that contains the sequence ESC 4, I find that the
 > resulting buffer is missing all the text from there up till the next
 > ESC (or till the end, if there is no such ESC).  I have determined
 > that the text is not merely missing from the display, but from the
 > buffer itself.  On the other hand, the file itself seems not to be
 > corrupted: if I view it using cat in the Cygwin shell, it is still
 > all there.  The buffer is not marked as modified.
 >
 > Is this a feature that I can turn off, or is it a bug?

It's a feature.  Notice the "-J" at the very beginning of the mode line:
that indicates the buffer's coding system.  Then `C-h C RET' or
`M-x describe-coding-system RET' explains:

	Coding system for saving this buffer:
	  J -- iso-2022-7bit-unix
	...

You can used `M-x find-file-literally' or `C-x RET c raw-text RET C-x
C-v' or `C-x RET c binary RET C-x C-v' to see the text as-is.  You can
prevent this particular coding system from ever being automatically
detected with (setq inhibit-iso-escape-detection t) in your .emacs file.

See the "Coding Systems ==============" and "Recognizing Coding Systems 
==========================" nodes of the
Emacs manual for much more information.

-- 
Kevin Rodgers