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  GNU Pth - GNU Portable Threads
 
  ChangeLog
  =========

  This is the list of all(!) changes to this Pth source tree. For a list
  of just the user-visible and/or major changes please have a look at
  the NEWS file.
     _   _ 
    / | / |
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  __|_(_)_|_______________________________________________________________
           
  Changes between 1.1.2 and 1.1.3 (23-Aug-1999 to xx-Aug-1999)

   *) Enhanced test program of AC_CHECK_STACKGROWTH in aclocal.m4 to
      make sure the test variables are not optimized away by the
      compiler and this way lead to incorrect check results.
      [Martin Kraemer <martin.kraemer@mch.sni.de>, Ralf S. Engelschall]

   *) Fixed default stack size: was 32*16384 (=512KB) instead
      of the intended 32*1024 (=32KB).
      [Ralf S. Engelschall]

   *) Added --enable-optimize flag to configure with selected
      standard optimization flags of GCC.
      [Ralf S. Engelschall]

   *) Added SUPPORT file to source tree.
      [Ralf S. Engelschall]

   *) Added test_philo, Dijkstra's Five Dining Philosophers ;)
      [Ralf S. Engelschall]

   *) Add "auto" qualifier to PTH_STACKGROWTH test program 
      to make sure the variables are placed into the stack.
      [Ralf S. Engelschall]

   *) Use predetermined $PLATFORM of configure also in Makefile
      [Ralf S. Engelschall]

  Changes between 1.1.1 and 1.1.2 (21-Aug-1999 to 23-Aug-1999)

   *) Fixed Makefile.in: pth_acdef.h and pth_acmac.h were not removed on
      "distclean" and this way they were accidently distributed.
      [Ralf S. Engelschall]
   
   *) Changed return type of pth_yield() from `void' to `int' to
      be able to return an error FALSE/EINVAL in case the `tid'
      argument specified an invalid or still not ready thread.
      [Kurt D. Zeilenga <Kurt@OpenLDAP.Org>, Ralf S. Engelschall]

   *) Fixed description of pth_yield() in pth.pod.
      [Kurt D. Zeilenga <Kurt@OpenLDAP.Org>, Ralf S. Engelschall]

  Changes between 1.1.0 and 1.1.1 (19-Aug-1999 to 21-Aug-1999)

   *) Changed pthread_yield_np() from `void' return type to `int' to allow the
      `#define sched_yield pthread_yield_np' work as expected, because
      sched_yield has `int' return type per SUSv2.
      [Kurt D. Zeilenga <Kurt@OpenLDAP.Org>, Ralf S. Engelschall]
   
   *) Fixed problems related to pthread_exit() and pth_exit(): The
      PTH_EVENT_FUNC internally was used incorrectly by pth_exit() and the
      implicit initialization was forgotten in pthread_exit().
      [Kurt D. Zeilenga <Kurt@OpenLDAP.Org>, Ralf S. Engelschall]

   *) Added consistency check for `timeout' attribute of pth_poll
      and various other EINVAL related checks to pth_event.c.
      [Ralf S. Engelschall]

   *) Added consistency check for `abstime' attribute of
      pthread_cond_timedwait().
      [Ralf S. Engelschall]

  Changes between 1.1b7 and 1.1.0 (18-Aug-1999 to 19-Aug-1999)
   
   *) Disable vendor typedefs in pthread.h.in because
      it caused problems under Solaris.
      [Ralf S. Engelschall]

   *) Cleaned up the sources a little bit more.
      [Ralf S. Engelschall]

   *) Updated rse-pmt.ps to v0.9.15
      [Ralf S. Engelschall]

  Changes between 1.1b6 and 1.1b7 (18-Aug-1999 to 18-Aug-1999)

   *) Added test for nested thread operation to test_std.c
      [Ralf S. Engelschall]

   *) Updated rse-pmt.ps to talk about the sigsetjmp(3) problems.
      [Ralf S. Engelschall]

   *) Enhanced the heart of Pth: pth_mctx_set().
      Instead of the real dispatching functions a plain setjmp(3)/longjmp(3)
      pair is used for the trampoline trick in order to avoid problems with
      sigjmp_buf-attached signal stacks on platforms where sigsetjmp(3) does
      more than it is usuallly expected. This especially fixes `thread spawns
      thread' problems under HPUX.
      [Ralf S. Engelschall, Aaron Metzger <ametzger@varcom.com>]

  Changes between 1.1b5 and 1.1b6 (17-Aug-1999 to 18-Aug-1999)

   *) Fixed return value of pth_write/pth_read.
      [Eric Newton <ecn@smart.net>, Ralf S. Engelschall]

   *) Fixed example in manual page (pth.pod): pth_load()
      is now pth_ctrl(PTH_CTRL_GETAVLOAD, ...)
      [Eric Newton <ecn@smart.net>]

   *) Fixed warning in pth_high.c related to implicit casting.
      [Ralf S. Engelschall]

   *) Added BS2000 support to config.guess/config.sub.
      [Martin Kraemer]

   *) Fixed a sigaltstack() call in pth_mctx.c: the return code
      was checked incorrectly.
      [Ralf S. Engelschall]
   
   *) Updated rse-pmt.ps
      [Ralf S. Engelschall, Eric Newton <ecn@smart.net>]

   *) Fixed a nasty bug in the thread stack allocation: A stack was also
      allocated for the main thread, but not used. The problem was that an
      allocated stack has a guardian and this way was checked each time and
      could lead to a bogus STACK OVERFLOW for the "main" thread.
      [Ralf S. Engelschall, Martin Kraemer]

  Changes between 1.1b4 and 1.1b5 (13-Aug-1999 to 17-Aug-1999)

   *) Added draft of forthcoming paper ``Portable Multithreading - The Signal
      Stack Trick Of User-Space Thread Creation'' to source tree under
      rse-pmt.ps. Hackers are encouraged to read this if they want to
      understand Pth's internals.
      [Ralf S. Engelschall]
   
   *) Source cleanups: added `extern' qualifier to function prototypes in
      pth.h.in and pthread.h.in; make compilation silent with both gcc 2.95.1 C
      and C++ frontends by fixing implicit type conversion situations, etc.
      [Ralf S. Engelschall]

   *) Return EBUSY instead of EAGAIN for pth_mutex_acquire() when the "try"
      argument is TRUE. This fixes especially the POSIX semantics of
      pthread_mutex_trylock().
      [Ralf S. Engelschall]

   *) Added pth_compat.c with strerror(3) replacement for SunOS.
      [Ralf S. Engelschall]

   *) Fixed pthread_{mutex,rwlock,cond}_destroy() functions.
      [Ralf S. Engelschall]

   *) Added support for `configure <platform-id>'.
      [Ralf S. Engelschall, Martin Kraemer <Martin.Kraemer@mch.sni.de>]

  Changes between 1.1b3 and 1.1b4 (11-Aug-1999 to 13-Aug-1999)
   
   *) Fixed blocking semantics of pth_writev().
      [Ralf S. Engelschall]

   *) Fixed a very nasty bug in pth_select(): The write fd_set was passed
      twice to the scheduler (once as the write fd_set and once as the
      execptional fd_set). This caused problems, because the event loop this
      way deleted bits in the write fd_set by accident and the return semantic
      was broken.
      [Ralf S. Engelschall]

   *) Added fallbacks for UIO_MAXIOV to pth.h and pthread.h
      [Ralf S. Engelschall]

   *) Remove locking check in pth_mutex_init() because this would only work
      with static vars where ANSI C guarranties an initialization with 0
      bytes.  
      [Martin Kraemer <Martin.Kraemer@mch.sni.de>]

   *) Fixed pth_write() semantics.
      [Ralf S. Engelschall]

  Changes between 1.1b2 and 1.1b3 (10-Aug-1999 to 11-Aug-1999)

   *) Overhauled pthread.h to make it better compile-able also under
      platforms where a vendor Pthread library exists.
      [Ralf S. Engelschall]
   
   *) Reordered ingredients of configure.in.
      [Ralf S. Engelschall]

   *) Fixed aclocal.m4: -g was incorrectly stripped.
      [Ralf S. Engelschall]

   *) Enhance pth_write(): In non-blocking (default) mode it now mimics the
      behaviour of write(2) more correctly by iterating until all data is
      written or an error occurs.
      [Ralf S. Engelschall]

  Changes between 1.1b1 and 1.1b2 (07-Aug-1999 to 10-Aug-1999)

   *) Fixed ring walking inside both public pth_msgport_find() function and
      the internal pth_mutex_releaseall() function.  
      [Laurent Vaucher <laurent.vaucher@ficsgrp.com>]

  Changes between 1.0.4 and 1.1b1 (03-Aug-1999 to 07-Aug-1999)

   *) Fixed test_select.c: a char has to be used for read(2) and not an int.
      [Ralf S. Engelschall]
   
   *) Fixed AC_CHECK_NSIG test and this way PTH_NSIG define.
      [Ralf S. Engelschall]

   *) Overhauled pth_mctx.c's internals according to latest algorithm of my
      paper ``Portable Multithreading - The Signal Stack Trick For User-Space
      Thread Creation''. Especially: sigstack had not restored stack
      correctly, the signal mask was not inherited correctly; Linux
      signal mask handling was incorrect, etc.
      [Ralf S. Engelschall]

   *) Adjusted variables in pth_mctx.c to use `volatile' qualifier.
      [Ralf S. Engelschall]

   *) Simplified Makefile.in a little bit by removing $(OBJS)
      [Ralf S. Engelschall]
   
   *) Replaced the run-time stack growth decision for the guardian in
      pth_tcb.c with a compile-time decision.
      [Ralf S. Engelschall]

   *) Completly rewritten the configure.in part which deals
      with the machine context (mctx) implementation: First SVR4/SUSv2
      makecontext(2) and friends are generally preferred.  Second, the user
      now can override the decisions via --with-mctx-{mth,dsp,stk}. Third, the
      pth_mctx.c source was enhanced by using skaddr_xxx() and sksize_xxx()
      macros which know through Autoconf checks how a stack has to be setup
      correctly for makecontext(2), sigaltstack(2) and sigstack(2).
      [Ralf S. Engelschall]

   *) Add support to pth_mctx.c for SVR4/SUSv2 makecontext(2)/swapcontext(2)
      and friends. This way Pth now is best prepared to cover forthcoming Unix
      flavors, because these are didicated and standadized functions for
      user-space context switching.
      [Ralf S. Engelschall]

   *) Completely overhauled aclocal.m4
      [Ralf S. Engelschall]

   *) Use GNU config.guess/config.sub instead of GNU shtool guessos
      for wider support inside GNU libtool.
      [Ralf S. Engelschall]

   *) Replaced switch() over long variables (which aren't covered by
      traditional C) with an if-else construct in pth_event.c to be more
      portable.
      [Ralf S. Engelschall]

   *) Fixed timeout handling in pth_select().
      [Ralf S. Engelschall]

   *) Don't free(2) application-supplied stacks on cleanups.
      [Ralf S. Engelschall]

   *) Don't allow an application to change the stack size or address on an
      pth_attr_t object when its attached to a thread (see pth_attr_of).
      [Ralf S. Engelschall]

   *) Added pth_ext.c for extensional functionality. As a first
      cut Sfio support is provided by an additional function pth_sfiodisc.
      This functions is always available, but only reasonably useable when Pth
      was built with Sfio support (--with-sfio option) and PTH_EXT_SFIO is
      then defined by pth.h. It is useful for applications which want to use
      the comprehensive Sfio I/O library with the Pth threading library. Then
      this function can be used to get an Sfio discipline structure (Sfdisc_t)
      which can be pushed onto Sfio streams (Sfio_t) in order to let this
      stream use pth_read(3)/pth_write(2) instead of read(2)/write(2). The
      benefit is that this way I/O on the Sfio stream does only block the
      current thread instead of the whole process. The application has to
      free(3) the Sfdisc_t structure when it is no longer needed.
      [Ralf S. Engelschall]

   *) Added `barrier' synchronization objects. These provide a way to let a
      group of threads wait at a barrier until the last reached the barrier.
      It's implemented on top of mutex and condition variable.
      [Ralf S. Engelschall]
   
   *) Replaced a bogus stdio fgetc() in test_select with pth_read().
      [Ralf S. Engelschall]

   *) Fixed internal pth_debug(3): it now preserved errno to make sure there
      is no run-time difference in semantics just because of debug messages.
      [Ralf S. Engelschall]

   *) Overhauled the filedescriptor handling:
      1. There is no longer a requirement to manually switch a filedescriptor
      into non-blocking mode in order to use it. This is automatically done
      temporarily inside Pth now. Instead when you now switch a filedescriptor
      explicitly into non-blocking mode, pth_read(3) or pth_write(3) will
      never block the current thread as it is the expected behaviour for
      non-blocking I/O.
      2. pth_nonblocking(3) was replaced by a more convinient pth_fdmode(3)
      function which can perform both get and set operations at once.
      [Ralf S. Engelschall]

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  __|_(_)___/_____________________________________________________________

  Changes between 1.0.4 and 1.0.5 (03-Aug-1999 to 10-Aug-1999)
   
   *) Backport from Pth 1.1b2:
      Fixed ring walking inside both public pth_msgport_find() function 
      and the internal pth_mutex_releaseall() function.  
      [Laurent Vaucher <laurent.vaucher@ficsgrp.com>]

   *) Backport from Pth 1.1b1:
      In pth_mctx.c the signal stack was not restored correctly.
      [Ralf S. Engelschall]

   *) Backport from Pth 1.1b1:
      Fixed test_select.c: a char has to be used for read(2) and not an int.
      And replaced a bogus stdio fgetc() in test_select with pth_read().
      [Ralf S. Engelschall]
   
   *) Backport from Pth 1.1b1:
      Fixed AC_CHECK_NSIG test and this way PTH_NSIG define.
      [Ralf S. Engelschall]

   *) Backport from Pth 1.1b1:
      Fixed timeout handling in pth_select().
      [Ralf S. Engelschall]

  Changes between 1.0.3 and 1.0.4 (30-Jul-1999 to 03-Aug-1999)

   *) Fixed two read/write calls: they didn't use the pth_sc wrapper.
      [Ralf S. Engelschall]

   *) Make pth_{read,write}() functions more POSIX compliant by returning 0
      when the nbytes argument is given as 0.  And make pth_{readv,writev}()
      functions more POSIX compliant by returning -1/EINVAL when the iovcnt
      argument is less or equal to 0.
      [Ralf S. Engelschall]

   *) Added missing readv/writev wrappers to pthread.c
      [Ralf S. Engelschall]

   *) Typo fixes in pth.pod
      [Eric Newton <ecn@smart.net>]

   *) Fixed special `--disable-static --enable-shared' situation.
      [Felix von Leitner <leitner@fefe.de>, Ralf S. Engelschall]

   *) Fixed `debug-xx' targets.
      [Ralf S. Engelschall]

  Changes between 1.0.2 and 1.0.3 (28-Jul-1999 to 30-Jul-1999)

   *) Fixed inconsistent and wrong API value: PTH_ATTR_NULL existed and was
      documented as PTH_ATTR_NONE. But actually the intended and intuitive
      value was PTH_ATTR_DEFAULT. !BE CAREFUL: This is an API change and
      requires adjustments in Pth applications!
      [Ralf S. Engelschall, Eric Newton <ecn@smart.net>]

   *) Make sure pthread.h.in doesn't redefine the poll(2) environment
      under built-time because it's already defined by the included pth.h.
      [Kriton Kyrimis <kyrimis@cti.gr>]

   *) Add readv/writev environment fallback definitions to pthread.h.in.
      [Ralf S. Engelschall]

   *) Support for AmigaOS in pthreads.c: timespec attributes have (correct)
      ts_ prefix under AmigaOS and not the (bogus) POSIX tv_ prefix
      [Kriton Kyrimis <kyrimis@cti.gr>]
      
   *) Add `#include <time.h>' for struct timespec to pthread.h.in
      and removed timespec references in pth.h.in.
      [Ralf S. Engelschall]

   *) Fixed documentation for pth_spawn() and pth_wait().
      [Ralf S. Engelschall, Eric Newton <ecn@smart.net>]

  Changes between 1.0.1 and 1.0.2 (22-Jul-1999 to 28-Jul-1999)

   *) Upgraded to GNU shtool 1.4.5.
      [Ralf S. Engelschall]

   *) Added `uninstall' target to Makefile
      [Ralf S. Engelschall]

   *) Cleanup package to conform to the GNU standards: added AUTHORS document;
      renamed CHANGES to ChangeLog and added NEWS document; renamed LICENSE to
      COPYING; renamed CREDITS to THANKS; added hint to bug-pth@gnu.org to
      pth.pod manual.
      [Ralf S. Engelschall]

   *) Fixed HAVE_SIGSTACK alternative in pth_mctx.c
      [Jim Jagielski <jim@jaguNET.com>]

   *) Removed internal "was_blocking" attribute in event structure
      because it was never used.
      [Ralf S. Engelschall]

   *) Fixed documentation of pth_xxx_init() synchronization functions.
      [Ralf S. Engelschall]

  Changes between 1.0.0 and 1.0.1 (16-Jul-1999 to 22-Jul-1999)

   *) Added missing documentation for pth_timeout().
      [Ralf S. Engelschall]

   *) Moved pthread_p{read,write}() to pth_high.c as pth_p{read,write}()
      and added syscall wrapper support for it.
      [Ralf S. Engelschall]

   *) Added support for readv(2) and writev(2): There are now
      four new API functions pth_readv, pth_readv_ev, pth_writev and
      pth_writev_ev. Additionally on platforms where no native
      readv(2)/writev(2) exists, the struct iovec is faked and the internal
      implementation is based on read(2)/write(2). This way the functionality
      is available everywhere. Finally, the syscall support was extended to
      cover readv and writev now, too.
      [Ralf S. Engelschall]

   *) Added support for FNDELAY to pth_nonblocking.
      [Ralf S. Engelschall]
   
   *) Cleaned up pthread.h and pth.h and added extra forward definitions for
      struct timeval/timespec to avoid problems on some platforms (like SCO).
      [Ralf S. Engelschall]

   *) Added "make check" as an alias for "make test"
      [Ralf S. Engelschall]

   *) Upgraded to GNU shtool 1.4.4 and use new `shtool tarball'
      [Ralf S. Engelschall]

  Changes between 1.0b8 and 1.0.0 (16-Jul-1999 to 16-Jul-1999)

   *) Fixed scheduler reinitialization.
      [Ralf S. Engelschall]

   *) Upgraded to GNU shtool 1.4.4-dev.
      [Ralf S. Engelschall]

   *) Cleaned up syscall stuff: usleep() is not longer mapped because it's too
      unstandardized, sigwait() is again mapped because it is standardized and
      those platforms which fail are broken.
      [Ralf S. Engelschall]

   *) Fixed pthread-config.in: -lpth => -lpthread
      [Ralf S. Engelschall]

   *) Downgraded required Autoconf version to 2.12
      [Ralf S. Engelschall]
 
   *) Moved pth_readline[_ev]() from the Pth API into test_common.c because
      this function is just a half-way solution (pth_read doesn't use the same
      buffer) and when one needs buffered I/O it's better to use a _real_ I/O
      library like Sfio, etc.
      [Ralf S. Engelschall]
 
   *) Cleanup to Makefile.in
      [Ralf S. Engelschall]
 
  Changes between 1.0b7 and 1.0b8 (14-Jul-1999 to 16-Jul-1999)
 
   *) Fixed result handling of stack growth detection.
      [Ralf S. Engelschall, Frank Carpenter <carpen@nortelnetworks.com>]
 
   *) Added explicit libtool --mode flags in Makefile.in
      to avoid compiler guessing problems on esoteric platforms.
      [Ralf S. Engelschall]
 
   *) Fixed broken condition variable handling: the scheduler 
      incorrectly checked the condition variable flags.
      [Ralf S. Engelschall, Andrew Hunter <esvce@dcs.warwick.ac.uk>]
 
   *) Allow main thread to be joinable to fulfill POSIX.
      [Ralf S. Engelschall]
 
   *) Fixed a nasty bug in the scheduler: the write and exceptional
      filedescriptor sets were not passed to the select(): ARGL!
      [Ralf S. Engelschall]
   
   *) Added implicit initialization to pth_syscall.c stuff
      and pthread.c stuff.
      [Ralf S. Engelschall]
 
   *) Fixed again static initializations via PTHREAD_XXX_INITIALIZER
      [Ralf S. Engelschall]
 
   *) Fixed again PTHREAD_ONCE_INIT
      [Ralf S. Engelschall]
 
   *) Added PTHREAD_CANCELED to pthread.h.
      [Ralf S. Engelschall]
 
   *) Fixed POSIX pthread_testcancel(): it is defined to have
      void return type and not int.
      [Ralf S. Engelschall]
 
  Changes between 1.0b6 and 1.0b7 (14-Jul-1999 to 14-Jul-1999)
 
   *) Replaced FALSE value for PTHREAD_ONCE_INIT in pthread.h with 0 to
      be not dependent on such defines.
      [Ralf S. Engelschall, Rick Brownrigg]
 
   *) Disabled syscall soft mapping for usleep because it causes prototype
      conflicts with unistd.h on some platforms due to the fact that usleep(3)
      is bad standardized. 
      [Ralf S. Engelschall, Rick Brownrigg]
 
   *) Added pthread_cancel() to POSIX emulation.
      [Ralf S. Engelschall, Rick Brownrigg]
 
   *) Fixed poll(2)/poll.h detection in Autoconf.
      [Ralf S. Engelschall, Igor A. Minyukoff <iam@inser.loniis.spb.su>]
 
  Changes between 1.0b5 and 1.0b6 (11-Jul-1999 to 14-Jul-1999)
 
   *) Fixed pth_attr_ctrl(): it failed with EACCES because 
      of incorrect comparisons
      [Igor A. Minyukoff <iam@inser.loniis.spb.su>]
 
   *) Replaced PTHREAD_{MUTEX,COND,RWLOCK}_INITIALIZER with an alternative
      implementation to allow the assignment to `static' variables, too.
      [Ralf S. Engelschall, Rick Brownrigg <brownrig@erg.sri.com>]
 
  Changes between 1.0b4 and 1.0b5 (08-Jul-1999 to 11-Jul-1999)
   
   *) Fixed pth_waitpid() semantics.
      [Ralf S. Engelschall]
 
   *) Added pth_poll() and pth_poll_ev() with the following trick: it is always
      present (independent whether the platform has poll(2) or not), because it
      is (AND HAS TO BE) internally based on pth_select(). The poll function
      wrapping support was added, too.
      [Ralf S. Engelschall]
 
   *) Moved pth_init() to the top of all test applications.
      [Ralf S. Engelschall]
 
   *) Added direct system call mapping support: --enable-syscall-soft
      enables #define's in pth.h and pthread.h which do a soft-mapping of e.g.
      read to pth_read. This is _always_ possible. --enable-syscall-hard
      enables the exportation of syscall wrappers (e.g. read) by the Pth
      library and the calling of the real system calls via syscall(2), hence
      this variant is only available when the platform supports syscall(2)
      [e.g. yes: *BSD, Linux, Solaris, HP/UX, IRIX, UnixWare; no: AIX, SCO5]
      
      For the soft variant the whole application sources have to include
      pth[read].h and existing libraries (like stdio!) can still block the
      whole process, while for the hard variant the application sources do not
      all have to include pth[read].h an existing libraries (including stdio!)
      magically use Pth's system call wrappers.
      [Ralf S. Engelschall]
 
   *) Speeded up `configure --help' by not creating the header
      [Ralf S. Engelschall]
 
   *) Added pth_select_ev() and pth_select() based on the new PTH_EVENT_SELECT
      and the old PTH_EVENT_TIME events which emulate 4.2BSD's select(2), but
      suspend only the current thread. Additionally added a select() wrapper to
      the POSIX wrapper API.
      [Ralf S. Engelschall]
 
   *) Added PTH_EVENT_SELECT which can be used to suspend the current thread
      until an event occured in one of three fd _sets_ similar to select(2) but
      without the timeout facility.
      [Ralf S. Engelschall]
 
   *) Upgraded to GNU shtool 1.4.3. This especially fixes
      the shared library generation under GNU/Linux now.
      [Ralf S. Engelschall]
 
   *) Added pth_abort() and a corresponding pthread_abort()
      for cruel ways to cancel a thread.
      [Ralf S. Engelschall]
 
   *) Fixed POSIX pread()/pwrite(): Their mutex variables have
      to be static variables and not local variables.
      [Ralf S. Engelschall]
 
   *) Added #define for POSIX sched_yield() to pthread.h.in
      [Ralf S. Engelschall]
 
  Changes between 1.0b3 and 1.0b4 (07-Jul-1999 to 08-Jul-1999)
 
   *) Added POSIX pread() and pwrite() [parallel I/O] emulation
      functions to pthread.{ch].
      [Ralf S. Engelschall]
 
   *) Removed double-definition of the fallback types in pthread.h.in.
      [Ralf S. Engelschall]
 
   *) Added pthread_atfork() to pthread.c
      [Ralf S. Engelschall]
 
   *) Added pth_atfork_{push,pop}() functions and moved them together with
      pth_fork() to a new pth_fork.c source files. Updated also the
      documentation to describe the new at-fork handlers.
      [Ralf S. Engelschall]
 
   *) Write still missing documentation for pth_cleanup_{push,pop}()
      [Ralf S. Engelschall]
 
   *) Fixed again pth_event_concat(): The last attempt was 
      to inefficient and still had a bug. 
      [Igor A. Minyukoff <iam@inser.loniis.spb.su>, Ralf S.  Engelschall]
 
   *) Cleaned up all name references: The official long name is `GNU Portable
      Threads', the official short name is `GNU Pth' and the common prefix is
      `pth_' and `PTH_'.
      [Ralf S. Engelschall]
 
  Changes between 1.0b2 and 1.0b3 (04-Jul-1999 to 07-Jul-1999)
 
   *) Remove a trailing comma inside an enum in pthread.h.in
      [Martin Kraemer <martin.kraemer@mch.sni.de>]
 
   *) Added two new API event-related functions which can be used to extract
      the contents of existing events: pth_event_typeof() and
      pth_event_extract().
      [Ralf S. Engelschall]
 
   *) Fixed pth_event_concat(): It was broken because it
      handled real/non-single-event event rings not correctly.
      [Igor A. Minyukoff <iam@inser.loniis.spb.su>, Ralf S. Engelschall]
 
   *) Fixed pth_event_walk(): It was broken for PTH_WALK_NEXT
      [Igor A. Minyukoff <iam@inser.loniis.spb.su>, Ralf S. Engelschall]
 
   *) Fixed memory leak in pth_join()
      [Igor A. Minyukoff <iam@inser.loniis.spb.su>]
 
   *) Fixed manual page pthread-config.pod
      [Ralf S. Engelschall]
 
   *) Upgraded to GNU shtool 1.4.1 and GNU libtool 1.3.3
      [Ralf S. Engelschall]
 
   *) Fixed test_pthread.c: sleep(3) requires unistd.h
      [Ralf S. Engelschall, Martin Kraemer <martin.kraemer@mch.sni.de>]
 
   *) Cleaned up --enable-batch/--enable-pthread
      [Ralf S. Engelschall]
 
  Changes between 1.0b1 and 1.0b2 (28-Jun-1999 to 04-Jul-1999)
 
   *) Upgraded to GNU shtool 1.4.0
      [Ralf S. Engelschall]
 
   *) Changed return value type of pth_version() from "int" to "long"
      to avoid problems with too large numbers.
      [Ralf S. Engelschall]
 
   *) Simplified internal representation of pth_once_t
      [Ralf S. Engelschall]
 
   *) !!ATTENTION!! Renamed _anything_ from the old
      coding-name nps/NPS to the new official name pth/PTH.
      [Ralf S. Engelschall]
 
   *) Added the new POSIX.1c pthread emulation library
      (pthread* files). It has to be enabled explicitly
      via --enable-pthread because it's disabled per default)
      [Ralf S. Engelschall]
 
   *) Enhanced pthread.pod manual page.
      [Ralf S. Engelschall]
 
  Changes between 0.9.21 and 1.0b1 (25-Jun-1999 to 28-Jun-1999)
 
   *) Added internal pth_util_cpystrn() to pth_util.c
      [Ralf S. Engelschall]
 
   *) removed pth_attr(), pth_priority(), pth_detach()
      [Ralf S. Engelschall]
 
   *) added new pth_attr_*() functions for manipulating pth_attr_t objects;
      this is now more flexible because those objects now can be also bound to
      threads when retrieved via pth_attr_of(). THIS IS A HEAVY BUT IMPORTANT
      API CHANGE! READ THE DOCS AND THE TEST PROGRAMS FOR DETAILS.  SORRY, BUT
      IS HAS TO BE DONE BEFORE WE ENTER THE STABLE 1.0 VERSIONS.
      [Ralf S. Engelschall]
 
   *) Added --enable-profile and --enable-batch to Autoconf
      [Ralf S. Engelschall]
 
   *) Updated pth.pod to reflect latest changes.
      [Ralf S. Engelschall]
 
   *) Renamed pth_state_* to upper case names.
      [Ralf S. Engelschall]
 
   *) Moved pth_sigmask() to pth_high.c
      [Ralf S. Engelschall]
 
   *) Renamed pth_sigraise() to pth_raise() and added support for
      per-thread signal delivery via pth_raise().
      [Ralf S. Engelschall]
 
   *) Renamed pth.c to pth_lib.c
      [Ralf S. Engelschall]
 
   *) Upgraded to GNU shtool 1.3.1
      [Ralf S. Engelschall]
 
   *) Added pth_version() function
      [Ralf S. Engelschall]
 
   *) Added a real test Makefile target via new test_std.c
      [Ralf S. Engelschall]
 
   *) Added more references to pth.pod
      [Ralf S. Engelschall]

      ___   ___  
     / _ \ / _ \ 
    | | | | (_) |
    | |_| |\__, |
  ___\___(_) /_/__________________________________________________________
 
  Changes between 0.9.20 and 0.9.21 (24-Jun-1999 to 25-Jun-1999)
 
   *) Upgraded to final shtool 1.3.0 release version
      [Ralf S. Engelschall]
 
   *) Removed all variables names from prototypes to avoid conflicts
      [Ralf S. Engelschall]
 
   *) Removed unnecessary casts for malloc() calls.
      [Ralf S. Engelschall]
 
   *) Added pth_sigraise() function for later implementing pthread_kill() and
      currently at least for testing whether a thread still exists in the
      system (by sending it a signal 0).
      [Ralf S. Engelschall]
 
   *) Renamed remaining XXX_INITIALIZER to XXX_INIT to be consistent with
      other init values.
      [Ralf S. Engelschall]
 
   *) Prefixed all pth_attr_t attributes with "at_"
      [Ralf S. Engelschall]
 
   *) Removed pth_equal(): we're not such crazy than POSIX...
      [Ralf S. Engelschall]
 
  Changes between 0.9.19 and 0.9.20 (21-Jun-1999 to 24-Jun-1999)
 
   *) Upgraded to latest shtool 1.3.0-dev
      [Ralf S. Engelschall]
 
   *) Changed pth_yield(void) to pth_yield(pth_t) to allow the specification of
      a thread which should be favored.  This allows the usage of the old
      concept of co-routines where a thread/routine switches to a particular
      target thread.
      [Ralf S. Engelschall]
 
   *) Added hint about async-safety to pth.pod
      [Ralf S. Engelschall]
 
   *) Added POSIX-style consistency wrapper pth_sigmask() for sigprocmask().
      [Ralf S. Engelschall]
 
   *) Added try argument to pth_mutex_acquire() to allow us later to
      emulate POSIX pthread_mutex_trylock()
      [Ralf S. Engelschall]
 
   *) Moved errno stuff to a new dedicated pth_errno.c source file
      [Ralf S. Engelschall]
 
   *) Changed function signatures to support return codes with errno
      [Ralf S. Engelschall]
 
   *) pth_exit(val) in the main() thread now really just terminated the thread
      and not immediately the process, i.e. the thread goes sleeping until all
      other threads are gone and then does an exit(val).
      [Ralf S. Engelschall]
 
  Changes between 0.9.18 and 0.9.19 (20-Jun-1999 to 21-Jun-1999)
 
   *) Added a POSIX style pth_detach()
      [Ralf S. Engelschall]
 
   *) Added pth_sync.c with POSIX style mutual exclusion locks (mutex),
      read-write locks (rwlock) and condition variable (cond) support
      [Ralf S. Engelschall]
 
   *) Added a trivial mutex demo to test_misc.c
      [Ralf S. Engelschall]
 
  Changes between 0.9.17 and 0.9.18 (18-Jun-1999 to 20-Jun-1999)
   
   *) Greatly extended the manual page pth.pod
      [Ralf S. Engelschall]
 
   *) Added inclusion hack to pthread.h.in
      [Ralf S. Engelschall]
 
   *) Added per thread cleanup functions pth_cleanup_{push,pop}() modeled
      directly after the POSIX pthread_cleanup_{push,pop}() functions
      [Ralf S. Engelschall]
 
   *) Fixed a memory leak related to pth_key_xxx().
      [Ralf S. Engelschall]
 
   *) Added internal pth_pqueue_contains() function
      [Ralf S. Engelschall]
 
   *) Added public API function pth_cancel(), pth_cancel_state() and
      pth_cancel_point() for thread cancellation support modeled after the
      POSIX thread cancellation facility.
      [Ralf S. Engelschall]
 
   *) Removed pthread.* stuff. It will be re-integrated later for Pth 1.1.x
      [Ralf S. Engelschall]
 
   *) Added cancellation flags to pth_attr().
      [Ralf S. Engelschall]
 
   *) Added cancellation demo support to test_sig.c
      [Ralf S. Engelschall]
 
  Changes between 0.9.16 and 0.9.17 (09-Jun-1999 to 18-Jun-1999)
 
   *) Removed pthread_p.h
      [Ralf S. Engelschall]
 
   *) Upgraded to latest shtool 1.3.0-dev
      [Ralf S. Engelschall]
 
   *) Added stack overflow detection: a SIGSEGV is created when a
      guardian memory address at the bottom of the stack was
      overridden. This SIGSEGV can be even catched by the
      application.
      [Ralf S. Engelschall]
 
  Changes between 0.9.15 and 0.9.16 (04-Jun-1999 to 09-Jun-1999)
 
   *) Some Autoconf related cleanups.
      [Ralf S. Engelschall]
 
   *) Added configure --enable-batch for FreeBSD port
      [Ralf S. Engelschall]
 
   *) Removed TODO file
      [Ralf S. Engelschall]
 
   *) Moved sigdelete stuff to new pth_util.c source
      [Ralf S. Engelschall]
 
   *) Added pth_sigwait_ev()
      [Ralf S. Engelschall]
 
   *) Updated pth.pod for recent changes
      [Ralf S. Engelschall]
 
   *) Fixed GNU/Linux libc v5 pth_mctx_set() variant
      [Ralf S. Engelschall, Felix von Leitner <leitner@fefe.de>]
 
  Changes between 0.9.14 and 0.9.15 (01-Jun-1999 to 04-Jun-1999)
 
   *) Upgraded to shtool 1.2.9
      [Ralf S. Engelschall]
 
   *) Avoid race conditions in emulated sigsetjmp() switching
      [Ralf S. Engelschall]
 
   *) Added test_sig.c
      [Ralf S. Engelschall]
 
   *) Fixed getsockopt() call: errlen wasn't initialized
      [Ralf S. Engelschall, Anton Umnikov <anton@rest.dvgu.ru>]
 
   *) Allow pth_event_walk() also to use PTH_UNTIL_OCCURRED
      to walk to the next/prev. occurred event in a ring
      [Ralf S. Engelschall]
 
   *) Completely overhauled the signal processing in the scheduler
      [Ralf S. Engelschall]
 
   *) Added pth_sigwait() with POSIX semantics
      [Ralf S. Engelschall]
 
   *) Fixed pth_join(): It returns -1 when only one thread is left
      [Ralf S. Engelschall]
 
   *) Autoconf now no longer adds -g for gcc unless --enable-debug
      [Ralf S. Engelschall]
 
  Changes between 0.9.13 and 0.9.14 (01-Jun-1999 to 01-Jun-1999)
 
   *) Simplified the event construction by removing unnecessary PTH_UNTIL_XX
      flags and renaming the remaining ones to PTH_UNTIL_YY_XXX.
      [Ralf S. Engelschall]
 
   *) Renamed PTH_EVENT_IRQ to PTH_EVENT_SIG and implemented it the first time
      via sigpending()/sigismember().
      [Ralf S. Engelschall]
 
   *) Documented the event facility in the manual page 
      [Ralf S. Engelschall]
 
   *) Switched TCB's name attribute from "char *" to "char[40]" and copy in the
      value when spawning. This allows applications to generate the name
      temporarily only.
      [Ralf S. Engelschall]
 
   *) Cleaned up source code at lots of edges...
      [Ralf S. Engelschall]
 
  Changes between 0.9.12 and 0.9.13 (30-May-1999 to 01-Jun-1999)
   
   *) Cleaned up Makefile.in even more
      [Ralf S. Engelschall]
 
   *) Add stackaddr argument to pth_attr() to allow the application
      to specificy a particular stack
      [Ralf S. Engelschall]
 
   *) Added pthread* files which will contain the POSIX.1c threading
      ("pthread") API wrapper for PTH. This is still work in progress and not
      enabled per default (one has to use --enable-pthread).
      [Ralf S. Engelschall]
 
   *) Added SunSoft's pthread_June95.ps document ("PThreads Summary")
      as pthreads.ps
      [Ralf S. Engelschall]
 
   *) Update pth.pod to reflect recent changes.
      [Ralf S. Engelschall]
 
   *) Optimized pth_time_cmp()
      [Ralf S. Engelschall]
 
   *) Added support for per-thread signal masks
      [Ralf S. Engelschall]
 
   *) Made pth_mctx_set() more robust: It now uses sigsuspend for
      waiting, correctly blocks signals and restores SIGUSR1 stuff
      [Ralf S. Engelschall]
 
   *) Fixed license messages in sources files
      [Ralf S. Engelschall]
 
   *) Removed const from pth_connect and pth_connect_ev to avoid problems
      [Ralf S. Engelschall]
 
   *) Make sure Autoconf doesn't add -lnsl twice
      [Ralf S. Engelschall]
 
   *) Cleaned up pth_mctx.c even more
      [Ralf S. Engelschall]
 
  Changes between 0.9.11 and 0.9.12 (28-May-1999 to 30-May-1999)
 
   *) Some fixes to test_httpd.c: init of addrlen, REQ_MAX handling
      [Ralf S. Engelschall]
 
   *) Allow pth_join(NULL) to join any available terminated thread
      [Ralf S. Engelschall]
 
   *) Fixed incorrect pth_event_concat() usages: terminated NULL was missing
      [Ralf S. Engelschall]
 
   *) Added pth_connect, pth_connect_ev and pth_accept_ev functions
      [Ralf S. Engelschall]
 
   *) Removed unnecessary b_extra stuff from pth_read/pth_write
      [Ralf S. Engelschall]
 
   *) Removed "intern" on pth_time(), it's a public API function
      [Ralf S. Engelschall]
 
   *) Added pth_timeout() constructor function
      [Ralf S. Engelschall]
 
   *) Fixed event handling for all pth_xxx_ev() functions
      [Ralf S. Engelschall]
 
   *) Use pth_readline_ev() in test_mp to show how pth_xxx_ev() works
      [Ralf S. Engelschall]
 
   *) Converted pth_nap() and pth_join() to use PTH_MODE_STATIC
      [Ralf S. Engelschall]
 
   *) Fixed event initialization in event rings
      [Ralf S. Engelschall]
 
   *) Kicked out the whole "occurred event ring" stuff because it's not really
      necessary (one can walk through a single ring and check for occurred
      events easily) and this way two nasty bugs can be fixed and the event
      manager simplified a lot. pth_wait() not has only one argument
      and this is a read-only one, i.e. only the occured flag is set
      in the events in this ring, but the ring is no longer changed.
      [Ralf S. Engelschall]
 
  Changes between 0.9.10 and 0.9.11 (28-May-1999 to 28-May-1999)
 
   *) Fix warnings in test_httpd.c
      [Ralf S. Engelschall]
 
   *) Upgraded to final shtool 1.2.8 
      [Ralf S. Engelschall]
 
   *) Added PTH_KEY_INIT 
      [Ralf S. Engelschall]
 
   *) Added PTH_MODE_STATIC for statically allocating
      a per-thread event. This is now used by the various high-level functions
      to avoid unnecessary alloc/free sequences.
      [Ralf S. Engelschall]
 
  Changes between 0.9.9 and 0.9.10 (25-May-1999 to 28-May-1999)
 
   *) Cleaned up Makefile.in
      [Ralf S. Engelschall]
 
   *) Upgraded to GNU libtool 1.3.2
      [Ralf S. Engelschall]
 
   *) Upgraded to new shtool 1.2.8 which includes scpp
      [Ralf S. Engelschall]
 
   *) Merged all pth_foo.h's into pth_foo.c's with the help of shtool scpp
      [Ralf S. Engelschall]
 
   *) Updated dependencies after pth_p.h overhauling
      [Ralf S. Engelschall]
 
   *) Added TODO file
      [Ralf S. Engelschall]
 
  Changes between 0.9.8 and 0.9.9 (24-May-1999 to 25-May-1999)
 
   *) Finally converted library generation to use GNU libtool
      [Ralf S. Engelschall]
 
   *) Add hints to BIND 8 and adns to manual page
      [Ralf S. Engelschall]
 
   *) Fixed memory leaks in test_httpd and test_mp
      [Ralf S. Engelschall, Flux <flux@iae.nl>]
 
   *) Fixed typos in manual page
      [Ralf S. Engelschall]
 
   *) Fix -lsocket -lnsl tests for Siemens platforms
      [Ralf S. Engelschall]
 
   *) Fix chmod in Autoconf stuff
      [Ralf S. Engelschall]
 
   *) Removed unneccessary pth_ring_linked()
      [Ralf S. Engelschall]
 
  Changes between 0.9.7 and 0.9.8 (23-May-1999 to 24-May-1999)
 
   *) Fixed bug in priority queue element counting (q_num)
      [Ralf S. Engelschall]
 
   *) pth_spawn() now inherits the attributes from the parent thread
      [Ralf S. Engelschall]
 
   *) Merged pth_stat() and pth_load() into a generic extensible pth_ctrl()
      [Ralf S. Engelschall]
 
   *) Added new pth_fork() function
      [Ralf S. Engelschall]
 
   *) Added depend target to Makefile.in and generated dependencies
      [Ralf S. Engelschall]
 
   *) Moved joinable argument from pth_attr() to the flags argument
      [Ralf S. Engelschall]
 
   *) Added PTH_CTRL_GETPRIO and PTH_CTRL_GETNAME.
      [Ralf S. Engelschall]
 
   *) Typo was everywhere: preemtive => preemptive 
      [Ralf S. Engelschall]
 
   *) Typo was everywhere: occured => occurred 
      [Ralf S. Engelschall]
 
   *) Finished manual page
      [Ralf S. Engelschall]
 
   *) Removed useless PTH_UNTIL_RUNNING
      [Ralf S. Engelschall]
 
   *) Replaced errno support with a better variant
      [Ralf S. Engelschall]
 
   *) Lots of small fixes and portability cleanups
      [Ralf S. Engelschall]
 
  Changes between 0.9.6 and 0.9.7 (22-May-1999 to 23-May-1999)
 
   *) Added PORTING document.
      [Ralf S. Engelschall]
 
   *) Added errno support (pth_errno.[ch]).
      [Ralf S. Engelschall]
 
   *) Added exponential average load calculations for scheduler.  The current
      load value can be retrieved by the application through pth_load().
      [Ralf S. Engelschall]
 
  Changes between 0.9.5 and 0.9.6 (21-May-1999 to 22-May-1999)
 
   *) Added more documentation.
      [Ralf S. Engelschall]
 
   *) Autoconf now determines the direction of stack grow and pth_mctx_set()
      uses this information for sigstack() now.
      [Ralf S. Engelschall]
 
   *) Fixed acconfig.h
      [Ralf S. Engelschall]
 
   *) Increased stacksizes (was too small for Solaris and friends)
      [Ralf S. Engelschall]
 
   *) Switched from BSD-style license to LGPL license
      [Ralf S. Engelschall]
 
   *) Fixed a nasty bug in scheduler:
      when a thread was moved from the wait to the ready queue, it's state
      wasn't changed to pth_state_ready. This way the next time it was handled
      it was incorrectly filed to the waiting queue (which caused core dumps
      because the ev_waiting/ev_occurred pointers didn't exist).  This way now
      the stuff works great also under Solaris!
      [Ralf S. Engelschall]
 
  Changes between 0.9.4 and 0.9.5 (21-May-1999 to 21-May-1999)
 
   *) Renamed pth_{get,set}specific() to pth_key_{get,set}data().
      [Ralf S. Engelschall]
 
   *) Renamed remaining pth_message_xxx() to pth_msgport_xxx()
      [Ralf S. Engelschall]
 
   *) Added pth_{readline,read,write}_ev() functions which are similar to
      pth_{readline,read,write}() but have an additional event argument which
      can be used for timeouts and other parallel events.
      [Ralf S. Engelschall]
 
  Changes between 0.9.3 and 0.9.4 (14-May-1999 to 21-May-1999)
 
   *) Added ring datastructures (pth_ring.[ch]).
      [Ralf S. Engelschall]
 
   *) Add an AmigaOS-style message port facility (pth_msg.[ch]).
      [Ralf S. Engelschall]
 
   *) Added a message port related test program (test_mp.c).
      [Ralf S. Engelschall]
 
   *) Fix scheduler event management bug: when no I/O events existed
      plus a next timer but other events (e.g. message ports) already occurred,
      the scheduler blocked instead of handling the already occurred events
      first.
      [Ralf S. Engelschall]
 
   *) Fix bug in event creating: the event occurrence flag has to be cleared in
      pth_wait() to avoid spinning events which were already occurred.
      [Ralf S. Engelschall]
 
  Changes between 0.9.2 and 0.9.3 (14-May-1999 to 14-May-1999)
 
   *) Added pth_once() for later (pthreads!)
      [Ralf S. Engelschall]
 
   *) Splitted pth.c into pth.c and pth_high.c
      [Ralf S. Engelschall]
 
   *) Added pth_data.[ch] with pthread style data storage stuff
      [Ralf S. Engelschall]
 
   *) Moved readline stuff from test_httpd to pth_high.c as pth_readline()
      [Ralf S. Engelschall]
 
   *) Removed debugging fprintf from test_httpd to speed it up
      [Ralf S. Engelschall]
 
   *) Fixed listen() call: now uses REQ_MAX for backlog and tests for -1
      [Ralf S. Engelschall]
 
   *) Fix a polling-related timer bug in the event manager
      [Ralf S. Engelschall]
 
  Changes between 0.9.1 and 0.9.2 (13-May-1999 to 14-May-1999)
 
   *) renamed pth_asynchronize() to pth_nonblocking()
      [Ralf S. Engelschall]
 
   *) removed implicit pth_nonblocking() calls
      [Ralf S. Engelschall]
 
   *) speeded up pth_accept by optimizing event alloc/free
      [Ralf S. Engelschall]
 
   *) cleaned up pth_waitpid
      [Ralf S. Engelschall]
 
   *) Changed semantics of pth_wait(var, NULL): it now means
      that the events in var are not removed (although their
      chanining might be changed)
      [Ralf S. Engelschall]
 
   *) Renamed internal pth_usleep() to pth_time_usleep()
      [Ralf S. Engelschall]
 
   *) Replaced pth_sleep() with pth_nap() and added
      two replacement functions: pth_sleep() for a variant
      of sleep(3) and pth_usleep() for a variant of usleep(3).
      [Ralf S. Engelschall]
 
   *) Optimized scheduler a little bit by inlining pth_time_{set,add,sub}
      [Ralf S. Engelschall]
 
   *) Added pth_pqueue_{head,walk} functions and used it in eventmanager
      [Ralf S. Engelschall]
 
   *) Rewrote pth_sched_eventmanager() without a surrounding loop
      [Ralf S. Engelschall]
 
   *) Implemented a readline() function to speedup test_httpd
      [Ralf S. Engelschall]
 
  Changes between 0.9.0 and 0.9.1 (12-May-1999 to 13-May-1999)
 
   *) Imported into CVS repository
      [Ralf S. Engelschall]
 
  Changes between GENESIS and 0.9.0 (Feb-1999 to 12-May-1999)
 
   *) Created initial version on FreeBSD
      [Ralf S. Engelschall]
 
   *) Ported to Linux
      [Ralf S. Engelschall]
 
