Using libnotify from Guile

Using libnotify from Guile

[Neil Jerram]

Hi Luis,

I noticed you asked about libnotify on IRC; unfortunately I wasn't quick
enough before you left the channel, but I had a quick play and found
that it was quite easy to generate a notification using the FFI:

(use-modules (system foreign))

(define libnotify (dynamic-link "libnotify"))

(define notify-init
  (pointer->procedure int
              (dynamic-func "notify_init" libnotify)
              (list '*)))

(notify-init (string->pointer "notify.scm"))

(define notify-notification-new
  (pointer->procedure '*
              (dynamic-func "notify_notification_new" libnotify)
              (list '* ; summary
                '* ; body
                '* ; icon
                )))

(define notify-notification-show
  (pointer->procedure int
              (dynamic-func "notify_notification_show" libnotify)
              (list '* ; notification
                '* ; &error
                )))

(notify-notification-show (notify-notification-new (string->pointer
"Hello!")
                           (string->pointer "Pleased to meet you")
                           %null-pointer)
              %null-pointer)

I thought you might like that; note that you'll also need "aptitude
install libnotify-dev", or your system's equivalent.

Regards,
    Neil

Re: Using libnotify from Guile

[Luis Felipe López Acevedo]

On 2016-01-04 13:26, Neil Jerram wrote:
> Hi Luis,
> 
> I noticed you asked about libnotify on IRC; unfortunately I wasn't 
> quick
> enough before you left the channel, but I had a quick play and found
> that it was quite easy to generate a notification using the FFI:

Oh, great Neil! Thank you very much. It works for me :)

-- 
Luis Felipe López Acevedo
http://sirgazil.bitbucket.org/

Re: Using libnotify from Guile

[Ludovic Courtès]

Neil Jerram <Neil.Jerram@metaswitch.com> skribis:

> I noticed you asked about libnotify on IRC

Also note that glibc built for the Linux kernel provides wrappers for a
bunch of inotify syscalls in <sys/inotify.h>:

--8<---------------cut here---------------start------------->8---
$ objdump -T .guix-profile/lib/libc.so.6 | grep inotify
00000000000e9cc0 g    DF .text  0000000000000021  GLIBC_2.9   inotify_init1
00000000000e9cf0 g    DF .text  0000000000000021  GLIBC_2.4   inotify_rm_watch
00000000000e9c90 g    DF .text  0000000000000021  GLIBC_2.4   inotify_init
00000000000e9c60 g    DF .text  0000000000000021  GLIBC_2.4   inotify_add_watch
--8<---------------cut here---------------end--------------->8---

So you could avoid libnotify altogether with things like:

  (dynamic-func "inotify_init" (dynamic-link))

Ludo’.

Re: Using libnotify from Guile

[Neil Jerram]

On 05/01/16 09:40, Ludovic Courtès wrote:
> Neil Jerram <Neil.Jerram@metaswitch.com> skribis:
>
>> I noticed you asked about libnotify on IRC
>
> Also note that glibc built for the Linux kernel provides wrappers for a
> bunch of inotify syscalls in <sys/inotify.h>:
>
> --8<---------------cut here---------------start------------->8---
> $ objdump -T .guix-profile/lib/libc.so.6 | grep inotify
> 00000000000e9cc0 g    DF .text  0000000000000021  GLIBC_2.9   inotify_init1
> 00000000000e9cf0 g    DF .text  0000000000000021  GLIBC_2.4   inotify_rm_watch
> 00000000000e9c90 g    DF .text  0000000000000021  GLIBC_2.4   inotify_init
> 00000000000e9c60 g    DF .text  0000000000000021  GLIBC_2.4   inotify_add_watch
> --8<---------------cut here---------------end--------------->8---
>
> So you could avoid libnotify altogether with things like:
>
>    (dynamic-func "inotify_init" (dynamic-link))
>
> Ludo’.
>
>

But isn't inotify (a Linux kernel subsystem for noticing changes to the 
filesystem) unrelated to libnotify (a thing for popping up a 
notification message on the desktop)?

Re: Using libnotify from Guile

[Ludovic Courtès]

Neil Jerram <neil@ossau.homelinux.net> skribis:

> But isn't inotify (a Linux kernel subsystem for noticing changes to
> the filesystem) unrelated to libnotify (a thing for popping up a
> notification message on the desktop)?

Oh!  Indeed, my bad.  Well, thanks for notifying me!  :-)

Ludo’.