Byte offset from point

Byte offset from point

[senny]

Hey there

I am looking for a way to get the exact byte-offset from the cursor
position. I need this value to call an external service. Is there a
way to achieve this in emacs?

Thanks in advance.

Regards,
senny

Re: Byte offset from point

[Teemu Likonen]

On 2009-08-12 11:44 (-0700), senny wrote:
> I am looking for a way to get the exact byte-offset from the cursor
> position. I need this value to call an external service. Is there a
> way to achieve this in emacs?

Perhaps this:

    (position-bytes (point))

Re: Byte offset from point

[senny]

On 12 Aug., 20:57, Teemu Likonen <tliko...@iki.fi> wrote:
> On 2009-08-12 11:44 (-0700), senny wrote:
>
> > I am looking for a way to get the exact byte-offset from the cursor
> > position. I need this value to call an external service. Is there a
> > way to achieve this in emacs?
>
> Perhaps this:
>
>     (position-bytes (point))

I tried that but it gave me incorrect results when dealing with
newlines on windows. The lisp function counted them as 1 byte but the
service i was calling counted them as 2 bytes.

Re: Byte offset from point

[Teemu Likonen]

On 2009-08-12 12:06 (-0700), senny wrote:
> On 12 Aug., 20:57, Teemu Likonen <tliko...@iki.fi> wrote:
>>     (position-bytes (point))
>
> I tried that but it gave me incorrect results when dealing with
> newlines on windows. The lisp function counted them as 1 byte but the
> service i was calling counted them as 2 bytes.

Maybe you can do the correction manually. Count newlines twice:
    
    (+ (position-bytes (point))
       (how-many "\n" 1 (point)))

Or something like that.

Re: Byte offset from point

[Eli Zaretskii]

> From: senny <yves.senn@gmail.com>
> Date: Wed, 12 Aug 2009 12:06:26 -0700 (PDT)
> 
> >     (position-bytes (point))
> 
> I tried that but it gave me incorrect results when dealing with
> newlines on windows. The lisp function counted them as 1 byte but the
> service i was calling counted them as 2 bytes.

If you want Emacs to account for the (potentially stripped) CR
characters, you need to visit the file without any code conversions,
e.g. with `find-file-literally' or with
`insert-file-contents-literally'.  Then position-bytes will count
correctly.

Alternatively, you could call count-lines-region and add one character
for each line before point.

If this does not help, perhaps consider telling more about the problem
you are trying to solve.