Re: Changing file end-of-line style

[Jambunathan K <kjambunathan@gmail.com>]

Suvayu Ali <fatkasuvayu+linux@gmail.com> writes:

> Hi Jambunathan,
>
> On Mon, Nov 05, 2012 at 06:38:31PM +0530, Jambunathan K wrote:
>> Suvayu Ali <fatkasuvayu+linux@gmail.com> writes:
>> 
>> > Hi,
>> >
>> > I sometimes have to deal with files created on Windows or Mac OSX.  When
>> > using emacs with X windows, I can click on the `(Mac)' or `(MS-DOS)'
>> > marker on the bottom left corner of the frame to switch to whichever
>> > style I want at the moment.
>> >
>> > How do I do this when running emacs as `emacs -nw'?  I tried looking for
>> > end-of-line with apropos, but could not find anything that seemed
>> > relevant.  Any ideas?
>> 
>> From (info "(emacs) Text and Binary")
>> 
>> ,---- 
>> |    To visit a file and specify whether it uses DOS-style or Unix-style
>> | end-of-line, specify a coding system (*note Text Coding::).  For
>> | example, `C-x <RET> c unix <RET> C-x C-f foobar.txt' visits the file
>> | `foobar.txt' without converting the EOLs; if some line ends with a
>> | carriage-return linefeed pair, Emacs will display `^M' at the end of
>> | that line.  Similarly, you can direct Emacs to save a buffer in a
>> | specified EOL format with the `C-x <RET> f' command.  For example, to
>> | save a buffer with Unix EOL format, type `C-x <RET> f unix <RET> C-x
>> | C-s'.  If you visit a file with DOS EOL conversion, then save it with
>> | Unix EOL format, that effectively converts the file to Unix EOL style,
>> | like `dos2unix'.
>> `----
>> 
>
> This works great!  I have a question though.  I was aware of the
> set-buffer-file-coding-system command; when I tried it I was prompted
> with utf-8[1] which did not seem to do anything.  What confuses me is
> this prompt along with separate markers on the modeline for charset and
> line ending style[2] led me to believe the coding system of the file is
> the charset (as in the characters used in the text) it is using, whereas
> line endings are set by something else.
>
> From your answer it seems that is not the case.  Does that mean there
> can be several coding system associated to a buffer?  Am I talking
> gibberish or does my question make any sense?

> Footnotes:
>
> [1] I use utf-8 for all text files.
>
> [2] There is a U for files with UTF-8 characters and DOS for files with
>     DOS style line endings at separate places on the bottom left of the
>     modeline.

At C-x C-m f prompt, you can choose utf-8-unix, utf-8-dos, utf-8-mac
apart from other options that start with utf-8.  The two things -
encoding and what constitues a eol character - are orthogonal to each
other.

Frankly, I don't know any more that what the manual suggests.