Your Emacs probably came with "Emacs Lisp Intro" C-hi.  That's a good place
to start.

On Mon, Feb 21, 2011 at 10:46 PM, Thomas Dean <tdean9db@gmail.com> wrote:

>
> Hi,
>
> I'm using Archlinux. I want to write a lisp to show the remaining
> capacity of the battery of the laptop. It is expected to work like
> this:
>
> 1. Read from /proc/acpi/battery/BAT0/state and obtain the remaining
> capacity of the battery.
> 2. Read from /proc/acpi/battery/BAT0/info and obtain the full capacity
> of the battery.
> 3. By calculating remaining / full, get the percentage and print it.
>
> I writing the following lisp but it seems that it doesn't work.
>
> ;--------------------------------LISP---------------------------------
>
> ; get remaining capacity
> (shell-command
>  "cat /proc/acpi/battery/BAT0/state | grep \"remaining capacity\" | sed
> \"s/^[a-z][a-z: ]*\([0-9][0-9]*\).*$/\1/g\""
>  "td-battery-temp-buffer")
> (set-buffer "td-battery-temp-buffer")
> (setq td-battery-full (string-to-number (buffer-string)))
> (erase-buffer)
>
> ; get full capacity
> (shell-command
>  "cat /proc/acpi/battery/BAT0/info | grep \"last full capacity\" | sed
> \"s/^[a-z][a-z: ]*\([0-9][0-9]*\).*$/\1/g\""
>  "td-battery-temp-buffer")
> (setq td-battery-full (string-to-number (buffer-string)))
>
> ; calculate percentage
> (message (concat "Remaining Capacity: " (number-to-string
> td-battery-remaining)
>                 "\nFull Capacity: " (number-to-string td-battery-full)))
>
> ; kill temporary buffer
> (set-buffer-modified-p nil)
> (kill-buffer)
>
> ;----------------------LISP END-------------------------------
>
> I'm new to lisp :-) So it maybe looks ugly.
>
> Could you please show me a good lisp that can finish this task?
>
> Thomas
>
> --
>
>


-- 
Le