path: root/ANNOUNCE

                 PTHREADS-WIN32 SNAPSHOT 2000-09-08
                 ----------------------------------
       Web Site: http://sources.redhat.com/pthreads-win32/
      FTP Site: ftp://sources.redhat.com/pub/pthreads-win32
        Coordinator: Ross Johnson <rpj@ise.canberra.edu.au>


We are pleased to announce the availability of a new snapshot of
Pthreads-win32, an Open Source Software (OSS) implementation of the
Threads component of the POSIX 1003.1c 1995 Standard for Microsoft's
Win32 environment. Some functions from POSIX 1003.1b are also
supported including semaphores. Other related functions include
the set of read-write lock functions.

Pthreads-win32 is free software, distributed under the GNU Library
General Public License (LGPL).

Please see the 'Acknowledgements' section at the end of this
announcement for the list of contributors.


Change Summary (since the last snapshot)
----------------------------------------

(See the ChangeLog file for details.)

New:
-	New non-portable function (see the README file):
		pthread_getw32threadhandle_np

Bugs fixed:
-       Calling pthread_cancel from non-POSIX threads fixed.
-       Possible deadlock threat using pthread_cond_broadcast() reduced.
-	TSD key creation race condition;
-	Other potential race conditions
	associated with initialising various
	pthreads objects.

Some new tests have been added.


Known bugs in this snapshot
---------------------------

1. Asynchronous cancelation only works on Intel X86 machines.

2. Running the test "join1.c" with the library built with Mingw32
and the GNUmakefile included, the test fails with a segmentation (invalid
page access) exception. The fault appears to be in the assembler code
emmitted by the compiler [to handle exception contexts] at the
end of the try block in ptw32_threadStart().

3. There are problems using the libpthreadw32.a stub archive derived
from either of pthreadVSE.dll or pthreadVCE.dll. The cleanup1.c test
fails. This is now an expected result of having different EH and cleanup
handler schemes in the library and application.


Caveats
-------

1. Due to what is believed to be a C++ compliance error in VC++,
if your application contains catch(...) blocks in your POSIX threads
then you will need to replace the "catch(...)" with the macro
"PtW32Catch", eg.

	#ifdef PtW32Catch
		PtW32Catch {
			...
		}
	#else
		catch(...) {
			...
		}
	#endif

Otherwise neither pthreads cancelation nor pthread_exit() will work
reliably.


Level of standards conformance
------------------------------

The following POSIX 1003.1c 1995 options are defined:

      _POSIX_THREADS
      _POSIX_THREAD_SAFE_FUNCTIONS
      _POSIX_THREAD_ATTR_STACKSIZE


The following POSIX 1003.1c 1995 options are not defined:

      _POSIX_THREAD_ATTR_STACKADDR
      _POSIX_THREAD_PRIORITY_SCHEDULING
      _POSIX_THREAD_PRIO_INHERIT
      _POSIX_THREAD_PRIO_PROTECT
      _POSIX_THREAD_PROCESS_SHARED

The following POSIX 1003.1b option is defined:

      _POSIX_SEMAPHORES

The following functions are implemented:

      ---------------------------
      PThreads
      ---------------------------
      pthread_attr_init
      pthread_attr_destroy
      pthread_attr_getdetachstate
      pthread_attr_getstackaddr
      pthread_attr_getstacksize
      pthread_attr_setdetachstate
      pthread_attr_setstackaddr
      pthread_attr_setstacksize

      pthread_create
      pthread_detach
      pthread_equal
      pthread_exit
      pthread_join
      pthread_once
      pthread_self

      pthread_cancel
      pthread_cleanup_pop
      pthread_cleanup_push
      pthread_setcancelstate
      pthread_setcanceltype
      pthread_testcancel
          
      ---------------------------
      Thread Specific Data   
      ---------------------------
      pthread_key_create
      pthread_key_delete
      pthread_setspecific
      pthread_getspecific
                
      ---------------------------
      Mutexes
      ---------------------------
      pthread_mutexattr_init
      pthread_mutexattr_destroy
      pthread_mutexattr_getpshared
      pthread_mutexattr_setpshared

      pthread_mutex_init
      pthread_mutex_destroy
      pthread_mutex_lock
      pthread_mutex_trylock      
      pthread_mutex_unlock

      ---------------------------
      Condition Variables
      ---------------------------
      pthread_condattr_init
      pthread_condattr_destroy
      pthread_condattr_getpshared
      pthread_condattr_setpshared

      pthread_cond_init
      pthread_cond_destroy
      pthread_cond_wait
      pthread_cond_timedwait
      pthread_cond_signal
      pthread_cond_broadcast  

      ---------------------------
      Read/Write Locks:
      ---------------------------
      pthread_rwlock_init
      pthread_rwlock_destroy
      pthread_rwlock_tryrdlock
      pthread_rwlock_trywrlock
      pthread_rwlock_rdlock
      pthread_rwlock_rwlock
      pthread_rwlock_unlock

      ---------------------------
      Semaphores
      ---------------------------
      sem_init               (POSIX 1b)
      sem_destroy            (POSIX 1b)
      sem_post               (POSIX 1b)
      sem_wait               (POSIX 1b)
      sem_trywait            (POSIX 1b)
      sem_open               (POSIX 1b - returns an error ENOSYS)
      sem_close              (POSIX 1b - returns an error ENOSYS)
      sem_unlink             (POSIX 1b - returns an error ENOSYS)
      sem_getvalue           (POSIX 1b - returns an error ENOSYS)

      ---------------------------
      RealTime Scheduling
      ---------------------------
      pthread_attr_getschedparam  
      pthread_attr_setschedparam  
      pthread_getschedparam
      pthread_setschedparam
      sched_get_priority_max (POSIX 1b)
      sched_get_priority_min (POSIX 1b)
      sched_yield            (POSIX 1b)

      ---------------------------
      Signals
      ---------------------------
      pthread_sigmask

      ---------------------------
      Non-portable routines (see the README file for usage)
      ---------------------------
      pthread_mutexattr_setforcecs_np
      pthread_getw32threadhandle_np

      ---------------------------
      Static Initializers (macros)
      ---------------------------
      PTHREAD_ONCE_INIT
      PTHREAD_MUTEX_INITIALIZER
      PTHREAD_COND_INITIALIZER
      PTHREAD_RWLOCK_INITIALIZER
      
      ---------------------------
      Thread-Safe C Runtime Library (macros)
      ---------------------------
      strtok_r
      asctime_r
      ctime_r
      gmtime_r
      localtime_r
      rand_r


The following functions are not implemented:
      
      ---------------------------
      RealTime Scheduling
      ---------------------------
      pthread_attr_getinheritsched
      pthread_attr_getschedpolicy
      pthread_attr_getscope
      pthread_attr_setinheritsched
      pthread_attr_setschedpolicy
      pthread_attr_setscope
      pthread_mutex_getprioceiling
      pthread_mutex_setprioceiling
      pthread_mutex_attr_getprioceiling
      pthread_mutex_attr_getprotocol
      pthread_mutex_attr_setprioceiling
      pthread_mutex_attr_setprotocol
      
      ---------------------------
      Fork Handlers
      ---------------------------
      pthread_atfork

      ---------------------------
      Stdio
      --------------------------- 
      flockfile
      ftrylockfile
      funlockfile
      getc_unlocked
      getchar_unlocked  
      putc_unlocked
      putchar_unlocked

      ---------------------------
      Thread-Safe C Runtime Library
      ---------------------------
      readdir_r
      getgrgid_r
      getgrnam_r
      getpwuid_r
      getpwnam_r
      
      ---------------------------
      Signals
      ---------------------------
      pthread_kill
      sigtimedwait
      sigwait
      sigwaitinfo
      
      
The library includes two non-API functions for creating cancellation
points in applications and libraries:
      
      pthreadCancelableWait
      pthreadCancelableTimedWait

      
Availability
------------ 

The prebuilt DLL, export libs (for both MSVC and Mingw32), and the header
files (pthread.h, semaphore.h, sched.h) are available along with the
complete source code.

The source code can be found at:

	ftp://sourcs.redhat.com/pub/pthreads-win32

and as individual source code files at

	ftp://sources.redhat.com/pub/pthreads-win32/source

The pre-built DLL, export libraries and include files can be found at:

	ftp://sources.redhat.com/pub/pthreads-win32/dll-latest


      
Mailing List 
------------  
      
There is a mailing list for discussing pthreads on Win32. To join,
send email to:

        pthreads-win32-subscribe@sourceware.cygnus.com
      

Application Development Environments
------------------------------------
      
MSVC:
MSVC using SEH works.
MSVC using C++ EH not tested.

Mingw32: (ftp://ftp.xraylith.wisc.edu/pub/khan/gnu-win32/mingw32/egcs-1.1.1/)
Mingw32 must use the thread-safe MSVCRT library (see the FAQ). You can link
against the export library libpthread32.a built under Mingw32
but you must run your application with the version of pthread.dll built
with MSVC. See the "Known bugs" section above.
      
Cygwin: (http://sourceware.cygnus.com/cygwin/)
Cygwin aims to provide a complete POSIX environment on top of Win32, including
threads. When this is complete, developers using Cygwin will not need
pthreads-win32. At this time, Cygwin has preliminary support for multithreaded
development, however, this is not turned on by default. We have not tested
pthreads-win32 against Cygwin.

Generally:
For convenience, the following pre-built files are available on the FTP site
(see Availability above):

        pthread.h       - for POSIX 1c threads
        semaphore.h     - for POSIX 1b semaphores
        sched.h         - for POSIX 1b scheduling
        pthread.dll     - built with MSVC cl compiler on NT4.0
        pthread.lib     - built with MSVC cl compiler on NT4.0
        libpthread32.a  - built with Mingw32 on Win98 (use with
                          MSVC pthread.dll for runtime)

These are the only files you need in order to build POSIX threads
applications for Win32 using either MSVC or Mingw32.
      
See the FAQ file in the source tree for additional information.


Building the library with MSVC
------------------------------

A simple makefile for building the library with MSVC is available. The
Makefile by default links the library to MSVCRT.DLL. If your application
uses another C runtime library like LIBCMT.LIB, please edit the Makefile to
avoid conflicts between C-libraries.

There is also a batch file "buildlib.bat" which will build the library.


Documentation
-------------

Currently, there is no documentation included in the package apart
from the copious comments in the source code.

For POSIX Thread API programming, several reference books are
available:  

        Programming with POSIX Threads
        David R. Butenhof
        Addison-Wesley (pub)

        Pthreads Programming
        By Bradford Nichols, Dick Buttlar & Jacqueline Proulx Farrell
        O'Reilly (pub)
      

Acknowledgements
----------------
      
This library is based substantially on a Win32 pthreads
implementation contributed by John Bossom <John.Bossom@cognos.com>.
      
The implementation of condition variables is derived from the work
of Douglas Schmidt et al
(http://www.cs.wustl.edu/~schmidt/win32-cv-1.html).

There is also a separate CONTRIBUTORS file. This file and others are
on the web site:

        http://sources.redhat.com/pthreads-win32

Enjoy!

Ross Johnson