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|
class EXAMPLE
--
-- This example shows how simulate `eif_adopt' and `eif_wean' as
-- they are described in ETL.
--
-- Note: it is not necessary to use these features when passing to
-- the C side the address of an Eiffel object which remains
-- referenced in the Eiffel side (and thus will not be garbage
-- collected).
--
-- To compile this example, use command :
--
-- compile -cecil cecil.se example c_prog.c
--
creation make
feature
make is
local
string: STRING; i: INTEGER
do
send_factory_to_c(Current)
-- Just play to remove or to add comments for the following
-- two lines (one or both):
call_eif_adopt_from_c
--call_eif_wean_from_c
-- The following loop should trigger the GC a few times (use
-- the -gc_info option to be sure that the GC is called).
-- As the allocated STRING in the following loop ("bar%N") has
-- exactely the same size as the one allocated on the C side
-- ("foo%N"), the former should overwrite the latter.
from
i := 100_000
until
i = 0
loop
-- Many many many allocation below:
string := ("bar%N").twin.twin.twin.twin
i := i - 1
end
string := string_back_to_eiffel
-- Should print "foo%N" or "bar%N".
io.put_string(string)
end
new_string(c_string: POINTER): STRING is
do
create Result.from_external_copy(c_string)
end
send_factory_to_c(factory: like Current) is
external "C"
end
string_back_to_eiffel: STRING is
external "C"
end
call_eif_adopt_from_c is
external "C"
end
call_eif_wean_from_c is
external "C"
end
end -- EXAMPLE
|
