/src/wrappers/ffi/examples/ffi_example.e

 1class FFI_EXAMPLE
 2	-- Sample usage of the foreign function interface library.
 3
 4	-- Invoking "puts" C function a couple of time with two different Eiffel strings.
 5
 6insert 
 7	FFI_TYPES
 8    FFI_MORE_EXTERNALS
 9	ANY -- To reobtain copy, default_create and is_equal.
10create {ANY} make
11
12feature {ANY} -- Creating
13	make
14		local msg: STRING; ptr: POINTER
15	do
16			create call.prepare(my_function, ffi_type_sint32, <<ffi_type_pointer>>)
17			print("Invoking 'puts'%N")
18			msg := "Hello Liberty!"
19			ptr := msg.to_external
20			call.invoke($call_result, <<$ptr>>)
21			print("Result of last call is "+call_result.out+"%N")
22
23			--call.invoke(resp,<<"Hello again!".to_external>>)
24			-- print("Result of last call is "+res.out+"%N")
25		end
26
27feature {ANY} 
28	call_result: INTEGER_64;
29	call: FFI_CALL
30	my_function: POINTER
31		external "C inline"
32		alias "puts"
33		end
34end
35
36-- Copyright (C) 2010-2017: Paolo Redaelli, 2013 Cyril Adrian
37
38-- This library is free software; you can redistribute it and/or
39-- modify it under the terms of the GNU Lesser General Public License
40-- as published by the Free Software Foundation; either version 2.1 of
41-- the License, or (at your option) any later version.
42--
43-- This library is distributed in the hope that it will be useful, but
44-- WITHOUT ANY WARRANTY; without even the implied warranty of
45-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
46-- Lesser General Public License for more details.
47--
48-- You should have received a copy of the GNU Lesser General Public
49-- License along with this library; if not, write to the Free Software
50-- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
51-- 02110-1301 USA
52