Usecase for inotify? Re: How to add content from a file to a table automatically

[Jambunathan K <kjambunathan@gmail.com>]

There is support for inotify in Emacs.  Last I heard, people were
interested in hearing use-cases.

I am not sure it qualifies as a minimal use-case.  But it is something
that comes out of real life.  So here it goes to emacs-devel...

Darlan Cavalcante Moreira <darcamo@gmail.com> writes:

> Is there a way to detect when a file changes and then add the content from
> it (if any, the file could be empty) to a specified org-mode table? Each
> line in that file is already constructed in a way that it could be copied
> and pasted to the table directly (but I can change that if it makes things
> easier).
>
> For instance, suppose I have the table below
>
>
> #+TBLNAME: FoodJanuary2013
> |   | *Place*   | *Date*           | *Debit (R$)* | *Credit (R$)* |
> |---+-----------+------------------+--------------+---------------|
> |   | Some name | [2013-01-07 Seg] |         0.00 |         10.00 |
> |---+-----------+------------------+--------------+---------------|
> | # |           | *Total*          |         0.00 |         10.00 |
> #+TBLFM: @3$4=vsum(@2..@-1);%.2f::@3$5=vsum(@2..@-1);%.2f
>
>
> and a file "food.txt" that was modified externally (Dropbox sync) and now
> has the content below
>
>
> | # | place name | [2013-01-08 Ter] | 0.00 | 12.50 |
> | # | other place | [2013-01-09 Qua] | 9.30 | 0.00 |
>
>
> I'd like the table to be automatically updated to include these two new
> lines so that it should now corresponds to
>
>
> #+TBLNAME: FoodJanuary2013
> |   | *Place*     | *Date*           | *Debit (R$)* | *Credit (R$)* |
> |---+-------------+------------------+--------------+---------------|
> |   | Some name   | [2013-01-09 Qua] |         0.00 |         10.00 |
> | # | place name  | [2013-01-08 Ter] |         0.00 |         12.50 |
> | # | other place | [2013-01-09 Qua] |         9.30 |          0.00 |
> |---+-------------+------------------+--------------+---------------|
> | # |             | *Total*          |         9.30 |         22.50 |
> #+TBLFM: @5$4=vsum(@2..@-1);%.2f::@5$5=vsum(@2..@-1);%.2f
>
>
> Adapting the formula as org-mode would automatically do if I typed enter
> twice before the last hline is important, but updating the total value is
> not (although nice), since I can do that with "C-u C-u C-c *" later when I
> actually see the table.
>
> After that the content of the file should be erased to prevent future
> additions of the same information.
>
> Any hints on how to do the different parts for this are welcome.
>
> --
> Darlan
>
> Ps: I use the latest org-mode and Emacs versions (from git and bzr,
> respectively) in a Linux box.
>
>
> The motivation for all this is that I use org-mode tables to control my
> expenses, but I want to be able to add new expenses from my android
> phone. Using the "tasker" app (REALLY good) I could create a simple UI to
> add the expense to a file that will be synced using Dropbox (one file for
> each category, which corresponds to a different table). All of this is
> working and now I the next step is the one described in this e-mail.
>
>

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