Re: [Caml-list] BUG in unix.ml (was: strange errors when linking lwt.unix)

[oliver <oliver@first.in-berlin.de>]

On Fri, Mar 15, 2013 at 11:38:06AM +0000, Jeremie Dimino wrote:
> On Fri, Mar 15, 2013 at 9:18 AM, Florian Hars <florian@hars.de> wrote:
> > It probably escaped notice so far because only lwt_unix does enough strange
> > things with signals in the default config to trigger it reliably.
> 
> Indeed.  BTW the only "strange" thing lwt does by default with signals
> is to set a handler for SIGCHLD.
> 
> Actually here is a way to reproduce this behavior without lwt on OSX
> and some other systems:
> 
>     # #load "unix.cma";;
>     # Sys.set_signal Sys.sigchld (Sys.Signal_handle ignore);;
>     - : unit = ()
>     # Unix.system "true";;
>     Exception: Unix.Unix_error (Unix.EINTR, "waitpid", "").
[...]


=========================================================
oliver@siouxsie:~$ ledit ocaml
        Objective Caml version 3.11.2

Unknown directive `require'.
# #load "unix.cma";;
# Sys.set_signal Sys.sigchld (Sys.Signal_handle ignore);;
- : unit = ()
# Unix.system "true";;
- : Unix.process_status = Unix.WEXITED 0
# 
=========================================================


=========================================================
oliver@siouxsie:~$ source ocamlbrew/ocaml-4.00.1/etc/ocamlbrew.bashrc 
oliver@siouxsie:~$ ledit ocaml
        OCaml version 4.00.1

Unknown directive `require'.
# #load "unix.cma";;
# Sys.set_signal Sys.sigchld (Sys.Signal_handle ignore);;
- : unit = ()
# Unix.system "true";;
- : Unix.process_status = Unix.WEXITED 0
# 
=========================================================


> 
> This will happen in any program setting a handler for SIGCHLD.

I wonder if "any program setting a handler for SIGCHLD" means
"program setting a handler for SIGCHLD", or only
"program setting a handler for SIGCHLD, using lwt".



Ciao,
   Oliver