maybe.. I cannot test because lwt.2.3.2 does not compile with 4.01.0.
```
# + ocamlfind ocamlc -c -g -I src/core -package unix -package bigarray -I src/unix -I tests -I syntax -I src/top -I src/text -I src/ssl -I src/simple_top -I src/react -I src/preemptive -I src/glib -I src/extra -I src/core -o src/unix/lwt_unix.cmi src/unix/lwt_unix.mli
# File "src/unix/lwt_unix.mli", line 298, characters 5-185:
# Error: This variant or record definition does not match that of type
#          Unix.open_flag
#        The field O_SHARE_DELETE is only present in the original definition.
# Command exited with code 2.
```