Warn when functions are used on unsupported platforms.

System/Posix/Files.hsc

@@ -380,6 +380,9 @@ setSymbolicLinkTimesHiRes name atime mtime =
       throwErrnoPathIfMinus1_ "setSymbolicLinkTimesHiRes" name $
         c_lutimes s times
 #else
+{-# WARNING setSymbolicLinkTimesHiRes
+ "System.Posix.Files.setSymbolicLinkTImesHiRes: not available on this platform"
+  #-}
 setSymbolicLinkTimesHiRes =
   error "setSymbolicLinkTimesHiRes: not available on this platform"
 #endif
@@ -406,6 +409,9 @@ touchSymbolicLink name =
   withFilePath name $ \s ->
     throwErrnoPathIfMinus1_ "touchSymbolicLink" name (c_lutimes s nullPtr)
 #else
+{-#
+  WARNING touchSymbolicLink "System.Posix.Files.touchSymbolicLink: not available on this platform"
+  #-}
 touchSymbolicLink =
   error "touchSymbolicLink: not available on this platform"
 #endif

System/Posix/Files/ByteString.hsc

@@ -382,6 +382,7 @@ setSymbolicLinkTimesHiRes name atime mtime =
       throwErrnoPathIfMinus1_ "setSymbolicLinkTimesHiRes" name $
         c_lutimes s times
 #else
+{-# WARNING setSymbolicLinkTimesHiRes "setSymbolicLinkTimesHiRes: not available on this platform" #-}
 setSymbolicLinkTimesHiRes =
   error "setSymbolicLinkTimesHiRes: not available on this platform"
 #endif
@@ -406,6 +407,7 @@ touchSymbolicLink name =
   withFilePath name $ \s ->
     throwErrnoPathIfMinus1_ "touchSymbolicLink" name (c_lutimes s nullPtr)
 #else
+{-# WARNING touchSymbolicLink "touchSymbolicLink: not available on this platform" #-}
 touchSymbolicLink =
   error "touchSymbolicLink: not available on this platform"
 #endif

System/Posix/Files/Common.hsc

@@ -486,6 +486,7 @@ setFdTimesHiRes (Fd fd) atime mtime =
   withArray [toCTimeVal atime, toCTimeVal mtime] $ \times ->
     throwErrnoIfMinus1_ "setFdTimesHiRes" (c_futimes fd times)
 #else
+{-# WARNING setFdTimesHiRes "setFdTimesHiRes: not available on this platform" #-}
 setFdTimesHiRes =
   error "setSymbolicLinkTimesHiRes: not available on this platform"
 #endif
@@ -502,6 +503,7 @@ touchFd :: Fd -> IO ()
 touchFd (Fd fd) =
   throwErrnoIfMinus1_ "touchFd" (c_futimes fd nullPtr)
 #else
+{-# WARNING touchFd "touchFd: not available on this platform" #-}
 touchFd =
   error "touchFd: not available on this platform"
 #endif

System/Posix/SharedMem.hsc

@@ -65,6 +65,7 @@ shmOpen name flags mode =
                        shm_open cname cflags mode
                  return $ Fd fd
 #else
+{-# WARNING shmOpen "System.Posix.SharedMem: shm_open: not available" #-}
 shmOpen = error "System.Posix.SharedMem:shm_open: not available"
 #endif
 
@@ -75,6 +76,7 @@ shmUnlink name = withCAString name shmUnlink'
     where shmUnlink' cname =
               throwErrnoIfMinus1_ "shmUnlink" $ shm_unlink cname
 #else
+{-# WARNING shmUnlink "System.Posix.SharedMem:shm_unlink: not available" #-}
 shmUnlink = error "System.Posix.SharedMem:shm_unlink: not available"
 #endif
 

System/Posix/Signals.hsc

@@ -358,6 +358,8 @@ installHandler :: Signal
                -> IO Handler            -- ^ old handler
 
 #ifdef __PARALLEL_HASKELL__
+{-# WARNING installHandler "installHandler: not available for Parallel Haskell"
+ - #-}
 installHandler =
   error "installHandler: not available for Parallel Haskell"
 #else

System/Posix/Temp.hsc

@@ -83,6 +83,7 @@ mkstemps prefix suffix = do
     h <- fdToHandle (Fd fd)
     return (name, h)
 #else
+{-# WARNING mkstemps "System.Posix.Temp.mkstemps: not available on this platform" #-}
 mkstemps = error "System.Posix.Temp.mkstemps: not available on this platform" 
 #endif
 

System/Posix/Temp/ByteString.hsc

@@ -84,6 +84,7 @@ mkstemps prefix suffix = do
     h <- fdToHandle (Fd fd)
     return (name, h)
 #else
+{-# WARNING mkstemps "System.Posix.Temp.mkstemps: not available on this platform"  #-}
 mkstemps = error "System.Posix.Temp.mkstemps: not available on this platform" 
 #endif
 

System/Posix/Terminal.hsc

@@ -121,6 +121,7 @@ foreign import ccall unsafe "__hsunix_ptsname"
 #else
 getSlaveTerminalName _ =
     ioError (errnoToIOError "getSlaveTerminalName" eNOSYS Nothing Nothing)
+{-# WARNING getSlaveTerminalName "getSlaveTerminalName: not available on this platform" #-}
 #endif
 
 -- -----------------------------------------------------------------------------
@@ -159,6 +160,10 @@ openPseudoTerminal = do
 # endif /* __hpux */
   return (Fd master, slave)
 
+# ifndef HAVE_PTSNAME
+{-# WARNING openPseudoTerminal "openPseudoTerminal: not available on this platform (neither OPENPTY nor PTSNAME available)" #-}
+# endif  /* HAVE_PTSNAME */
+
 -- Push a STREAMS module, for System V systems.
 pushModule :: Fd -> String -> IO ()
 pushModule (Fd fd) name =

System/Posix/Terminal/ByteString.hsc

@@ -128,6 +128,7 @@ getSlaveTerminalName (Fd fd) = do
 foreign import ccall unsafe "__hsunix_ptsname"
   c_ptsname :: CInt -> IO CString
 #else
+{-# WARNING getSlaveTerminalName "getSlaveTerminalName: not available on this platform" #-}
 getSlaveTerminalName _ =
     ioError (errnoToIOError "getSlaveTerminalName" eNOSYS Nothing Nothing)
 #endif

System/Posix/Unistd.hsc

@@ -145,6 +145,7 @@ foreign import ccall safe "usleep"
 -- /GHC Note/: the comment for 'usleep' also applies here.
 nanosleep :: Integer -> IO ()
 #ifndef HAVE_NANOSLEEP
+{-# WARNING nanosleep "nanosleep: not available on this platform" #-}
 nanosleep = error "nanosleep: not available on this platform"
 #else
 nanosleep 0 = return ()

System/Posix/User.hsc

@@ -211,6 +211,7 @@ foreign import capi unsafe "HsUnix.h getgrgid_r"
   c_getgrgid_r :: CGid -> Ptr CGroup -> CString
 		 -> CSize -> Ptr (Ptr CGroup) -> IO CInt
 #else
+{-# WARNING getGroupEntryForID "System.Posix.User.getGroupEntryForID: not supported" #-}
 getGroupEntryForID = error "System.Posix.User.getGroupEntryForID: not supported"
 #endif
 
@@ -230,6 +231,7 @@ foreign import capi unsafe "HsUnix.h getgrnam_r"
   c_getgrnam_r :: CString -> Ptr CGroup -> CString
 		 -> CSize -> Ptr (Ptr CGroup) -> IO CInt
 #else
+{-# WARNING getGroupEntryForName "System.Posix.User.getGroupEntryForName: not supported" #-}
 getGroupEntryForName = error "System.Posix.User.getGroupEntryForName: not supported"
 #endif
 
@@ -261,6 +263,7 @@ foreign import ccall unsafe "setgrent"
 foreign import ccall unsafe "endgrent"
   c_endgrent :: IO ()
 #else
+{-# WARNING getAllGroupEntries "System.Posix.User.getAllGroupEntries: not supported" #-}
 getAllGroupEntries = error "System.Posix.User.getAllGroupEntries: not supported"
 #endif
 
@@ -332,6 +335,7 @@ getUserEntryForID uid = do
 foreign import ccall unsafe "getpwuid" 
   c_getpwuid :: CUid -> IO (Ptr CPasswd)
 #else
+{-# WARNING getUserEntryForID "System.Posix.User.getUserEntryForID: not supported" #-}
 getUserEntryForID = error "System.Posix.User.getUserEntryForID: not supported"
 #endif
 
@@ -360,6 +364,7 @@ getUserEntryForName name = do
 foreign import ccall unsafe "getpwnam" 
   c_getpwnam :: CString -> IO (Ptr CPasswd)
 #else
+{-# WARNING getUserEntryForName "System.Posix.User.getUserEntryForName: not supported" #-}
 getUserEntryForName = error "System.Posix.User.getUserEntryForName: not supported"
 #endif
 
@@ -385,6 +390,7 @@ foreign import ccall unsafe "setpwent"
 foreign import ccall unsafe "endpwent"
   c_endpwent :: IO ()
 #else
+{-# WARNING getAllUserEntries "System.Posix.User.getAllUserEntries: not supported" #-}
 getAllUserEntries = error "System.Posix.User.getAllUserEntries: not supported"
 #endif