Re: [Pharo-users] [squeak-dev] FFI syntax

Oct. 16, 2014


      2014-10-16 11:53 GMT+02:00 Annick Fron <list@afceurope.com>:
...
Hi Eliot,
Thank you. Meanwhile I have tried to use only pointers to structs by
writing some C code.
I confirm that in Pharo you can load FFI and OldAlien in the
ConfigurationBrowser.
Yet it seems both FFI and Alien versions in the ConfigurationBrowser are
behind the squeak repositories.
I did not try if  the new versions worked.
I have posted some time ago an example for X11 windows on Linux, and I
never got an answer why it was failing.
actually I did answer ;)
http://forum.world.st/FFI-on-Linux-again-td4780236.html
and  you changed the argument "ourWindow" to "ourWindow xid" like I
proposed. But yes,
actually this didn't help, I guess. You still get the error "bad argument" ?

My next bet would be:
Maybe we cannot mix Alien calls with (old) FFI structures (display is a
externalstructure defined for FFI).
...
It was the following
testGetOurWindowLocation
  "self new testGetOurWindowLocation"
| display ourWindow aParent anX anY aWidth aHeight aBorderWidth aDepth |
  display := X11Display XOpenDisplay: nil.
  ourWindow := display ourWindow.
  (Alien lookup: 'XGetGeometry' inLibrary: 'X11')
      primFFICallResult: nil
      withArguments:
          {display.
          ourWindow xid.
          (aParent := Alien new: 4).
          (anX := Alien new: 4).
          (anY := Alien new: 4).
          (aWidth := Alien new: 4).
          (aHeight := Alien new: 4).
          (aBorderWidth := Alien new: 4).
          (aDepth := Alien new: 4)}.
  (anX unsignedLongAt: 1) inspect.
Has anybody looked at Wayland (replacement of X11) on Linux ?
Annick
Le 15 oct. 2014 Ã  19:18, Eliot Miranda <eliot.miranda@gmail.com> a Ã©crit :
Hi Annick,
On Wed, Oct 15, 2014 at 7:57 AM, Annick Fron <list@afceurope.com> wrote:
...
What is the syntax to describe an external structure with an array of int
of size 6 ?
I know only the syntax
fields
^#(
(param1 âlongâ)
(param2 âlongâ)
(param3 âlongâ)
(param4 âlongâ)
(param5 âlongâ)
(param6 âlongâ)
)
Hmm.  Good question.  It seems you can write
fields
"IAXCallStateEvent defineFields"
^#(
(type 'long')
(callNo 'long')
(state 'long')
(format 'long')
(vformat 'long')
(remote 'char[256]')
(remoteName 'char[256]')
(local 'char[256]')
(localContext 'char[256]')
)
But as a community we really need to document the FFI more thoroughly :-/
...
Annick
--
best,
Eliot
Le 15 oct. 2014 Ã  19:18, Eliot Miranda <eliot.miranda@gmail.com> a Ã©crit :
Hi Annick,
On Wed, Oct 15, 2014 at 7:57 AM, Annick Fron <list@afceurope.com> wrote:
...
What is the syntax to describe an external structure with an array of int
of size 6 ?
I know only the syntax
fields
^#(
(param1 âlongâ)
(param2 âlongâ)
(param3 âlongâ)
(param4 âlongâ)
(param5 âlongâ)
(param6 âlongâ)
)
Hmm.  Good question.  It seems you can write
fields
"IAXCallStateEvent defineFields"
^#(
(type 'long')
(callNo 'long')
(state 'long')
(format 'long')
(vformat 'long')
(remote 'char[256]')
(remoteName 'char[256]')
(local 'char[256]')
(localContext 'char[256]')
)
But as a community we really need to document the FFI more thoroughly :-/
...
Annick
--
best,
Eliot

Re: [Pharo-users] [squeak-dev] FFI syntax

Nicolai Hess