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 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 . 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