]> Here is an implementation of callcc for OCaml using fork. The only problems are: - I did not test it (but it should work) - The limited number of fork calls Note: the implementation of fork on Linux, makes a minimum of page copying, so it should be reasonably fast -- callcc.mli -- (* callcc fn: standard callcc, uses exit code 3 for internal use. *) val callcc : (('a -> 'b) -> 'a) -> 'a ---------------- -- callcc.ml --- open Unix open Sys let all_signals = [ sigabrt; (* Abnormal termination *) sigalrm; (* Timeout *) sigfpe; (* Arithmetic exception *) sighup; (* Hangup on controlling terminal *) sigill; (* In id hardware instruction *) sigint; (* Interactive interrupt (ctrl-C) *) sigkill; (* Termination (cannot be ignored) *) sigpipe; (* Broken pipe *) sigquit; (* Interactive termination *) sigsegv; (* In id memory reference *) sigterm; (* Termination *) sigusr1; (* Application-defined signal 1 *) sigusr2; (* Application-defined signal 2 *) (* sigchld; Child process terminated, do not ignore that one !*) sigcont; (* Continue *) sigstop; (* Stop *) sigtstp; (* Interactive stop *) sigttin; (* Terminal read from background process *) sigttou; (* Terminal write from background process *) sigvtalrm; (* Timeout in virtual time *) sigprof (* Profiling interrupt *) ] let ignore_all_signals () = let previous = List.map (fun s -> try signal s Signal_ignore with Sys_error _ -> Signal_ignore) all_signals in fun () -> List.iter2 (fun s b -> try set_signal s b with Sys_error _ -> ()) all_signals previous let callcc (fn : ('a -> 'b) -> 'a) = let filename = Filename.temp_file "callcc" "val" in let gn (x : 'a) = let ch = open_out filename in Marshal.to_channel ch x [Marshal.Closures]; close_out ch; exit 3 in let restore_signals = ignore_all_signals () in let pid = fork () in if pid = 0 then begin restore_signals (); fn gn end else let rec kn pid = match waitpid [] pid with _, WEXITED 3 -> let ch = open_in filename in let r = Marshal.from_channel ch in close_in ch; remove filename; let pid = fork () in if pid = 0 then (restore_signals (); r) else kn pid | _, WEXITED n -> exit n | _, _ -> exit 1 in kn pid ---------------- -- Christophe Raffalli Université de Savoie Batiment Le Chablais, bureau 21 73376 Le Bourget-du-Lac Cedex tél: (33) 4 79 75 81 03 fax: (33) 4 79 75 87 42 mail: Christophe.Raffalli@univ-savoie.fr www: http://www.lama.univ-savoie.fr/~RAFFALLI --------------------------------------------- IMPORTANT: this mail is signed using PGP/MIME At least Enigmail/Mozilla, mutt or evolution can check this signature ---------------------------------------------