bug#20707: [PROPOSED PATCH] Use curved quoting in C-generated errors

[Paul Eggert <eggert@cs.ucla.edu>]

On 06/01/2015 03:49 AM, Alan Mackenzie wrote:
> Currently, we can grep C source code (whether on the command line or
> within Emacs), specifically specifying quote characters like " (even if
> they have to be escaped).

Having just gone through this exercise, I can say that it doesn't work 
as well as I had hoped.  Characters are sometimes escaped, sometimes 
not, and even something easy like searching for '`' finds many false 
hits in comments.

> OK, there may be some arcane way of specifying these curly quotes

Hmm, well, it's not arcane for me.  This shell command:

    grep ‘ *.c

generates all .c lines that contain left single quotation mark in a 
string (after the proposed patch is applied).  This is simpler than any 
shell command to find apostrophe or double-quote or grave accent.

> Curly quotes display as ? on my terminal, sometimes inverted.

That's not good.  What terminal are you using, and why does it not 
handle UTF-8?  What is your operating system and locale settings? If 
this is a common problem among Emacs developers, I suppose we'll have to 
come up with a different way.