[project @ 2002-12-05 14:20:56 by stolz]

Add SA_RESETHAND (aka SA_ONESHOT) support.
Requested by: John Meacham

> module Main where

> import System.Posix.Signals

> main = do
>   installHandler sigUSR1 (Catch (print "usr1")) Nothing
>   installHandler sigUSR2 (CatchOnce (print "usr2")) Nothing
>   _ <- getLine
>   return ()

diff --git a/System/Posix/Signals.hsc b/System/Posix/Signals.hsc
index 8866bf5..8c44c2c 100644 (file)
--- a/System/Posix/Signals.hsc
+++ b/System/Posix/Signals.hsc
@@ -249,6 +249,7 @@ data Handler = Default
              | Ignore
             -- not yet: | Hold 
              | Catch (IO ())
+             | CatchOnce (IO ())
 
 installHandler :: Signal
                -> Handler
@@ -271,9 +272,8 @@ installHandler int handler maybe_mask = do
       rc <- case handler of
              Default -> stg_sig_install int (#const STG_SIG_DFL) p_sp mask
              Ignore  -> stg_sig_install int (#const STG_SIG_IGN) p_sp mask
-             Catch m -> do sptr <- newStablePtr m
-                           poke p_sp sptr
-                           stg_sig_install int (#const STG_SIG_HAN) p_sp mask 
+             Catch m -> install'' m p_sp mask int (#const STG_SIG_HAN)
+             CatchOnce m -> install'' m p_sp mask int (#const STG_SIG_RST)
 
       case rc of
        (#const STG_SIG_DFL) -> return Default
@@ -284,6 +284,11 @@ installHandler int handler maybe_mask = do
                m     <- deRefStablePtr osptr
                return (Catch m)
 
+    install'' m p_sp mask int reset = do
+      sptr <- newStablePtr m
+      poke p_sp sptr
+      stg_sig_install int reset p_sp mask
+
 foreign import ccall unsafe
   stg_sig_install :: CInt -> CInt -> Ptr (StablePtr (IO ())) -> Ptr CSigset
         -> IO CInt