Re: [Haskell-cafe] FFI question

9 Sep 2014


      On Tue, Sep 9, 2014 at 10:36 PM, Vasili I. Galchin  wrote:
...
Adam,
Did a find/grep under my posix-realtime  directory .. no
definition of MCL_CURRENT, MCL_FUTURE or MCL_CURRENTandFUTURE!! But If
I comment out the case arm MCL_CURRENTandFUTURE in my LockMem.hsc file
and run "cabal build" from the directory where my *.cabal file lives
.. clean compile ... Sigh!??!!
Vasya
On Mon, Sep 8, 2014 at 7:36 AM, adam vogt  wrote:
...
Hi Vasili
Does the sys/mman.h or another included header actually define
MCL_CURRENTandFUTURE?
Regards,
Adam
On Sep 8, 2014 4:45 AM, "Vasili I. Galchin"  wrote:
...
Following is a fragment generated by hsc2hs from LockedMem.hsc:
#line 93 "LockedMem.hsc"
    hsc_const (MCL_CURRENTandFUTURE);
    hsc_fputs (")\n"
           "", hsc_stdout());
    hsc_line (94, "LockedMem.hsc");
    hsc_fputs ("\n"
           "foreign import ccall unsafe \"sys/mman.h mlockall\"\n"
           "    c_mlockall :: CInt -> IO CInt\n"
           "\n"
           "\n"
           "-- | unlock all mapped pages of a process!\n"
           "unlockAllMemory :: IO ()   \n"
           "unlockAllMemory = do\n"
           "   throwErrnoIfMinus1 \"unlockAllMemory\" (c_munlockall)\n"
           "   return ()\n"
           "\n"
           "foreign import ccall unsafe \"sys/mman.h munlockall\"\n"
           "    c_munlockall :: IO CInt\n"
           "", hsc_stdout());
    return 0;
On Mon, Sep 8, 2014 at 2:11 AM, Vasili I. Galchin 
wrote:
...
Hello,
I need memory refreshing about FFI because I need to fix a bug
(plus I got down a rat hole because of Ukraine war :-(). Following a
snippet of something I wrote:
-- | lock all of the memory space of a process
lockAllMemory :: LockAllFlags -> IO ()
lockAllMemory flags = do
    throwErrnoIfMinus1 "lockAllMemory" (c_mlockall cflags)
    return ()
  where
    cflags = case flags of
                   CURRENT          -> (#const MCL_CURRENT)
                   FUTURE           -> (#const MCL_FUTURE)
                   CURRENTandFUTURE -> (#const MCL_CURRENTandFUTURE)
it is a file called LockedMem.hsc and the third arm CURRENTandFUTURE I
just added to fix the this  bug ..
MCL_CURRENTandFUTURE ends up in LockedMem_make.c(sp??) but I get a
undeclared nasty message when I try to build LockedMem.hsc... my
bad... . Please help so I can go back to help Ukraine.
Kind regarsd,
Vasya

Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe