``A Library Implementation of POSIX Threads under SunOS/Solaris'', Version 2.2

The PART (POSIX / Ada-Runtime Project) is happy to announce a new
release of the C sources of the Pthreads library.

ftp-site:  ftp.cs.fsu.edu
internet#: 128.186.121.27
directory: /pub/PART
files:     pthreads.tar.Z, pthreads_serf92.ps.Z, pthreads_usenix93.ps.Z,
	   pthreads_interface.ps.Z, rtoss94.ps.Z

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As part of the PART project we have been designing and implementing a
library package of preemptive threads which is compliant with POSIX
1003.4a Draft 6. A description of the interface for our Pthreads
library is also available on ftp. Our implementation is limited to the
Sun SPARC architecture and SunOS 4.1.x or Solaris. We do not make any
use of Sun's light-weight processes to achieve better performance
(with one I/O-related exception).

What's NEW:
  .bug fix: Makefile comments about the use of -traditional for assembling
  .bug fix: pthread.h for gcc distinguish SOLARIS/SunOS 4.1x (_PARAMS)
  .bug fix: pthread_unlock_stack() only called in sighandler on stack overflow
  .bug fix: pthread_lock_stack() not called for main thread,
   as a side-effect, the stack of the main thread can currently not be
   unlocked, i.e. no signal handler can recover from stack overflow on the
   main thread.
  .bug fix: The scheduler sets mac_pthread_self() to NO_PTHREAD after freeing
   a TCB. The signal handler has been adjusted accordingly.
   (problem reported by: Nikolaus.Koenig@aaf.alcatel.at)
  .jmp_buf is no longer a struct but rather an array (conforms with ANSI C)
  .portability: There is no assmebly code left (except invoking pthread_init
   in some magical way) if you choose the compile options in the Makefile
   for maximum portability. The only problems remaining are the paths and
   names of include files and the initialization of Pthreads
   (C pragma init under Solaris, assembly routine start_float under
   SunOS 4.1.x) which requires OS-specific treatment.
   Otherwise, Pthreads should be easily portable for BSD, SVR4, or POSIX
   compliant UNIX systems.
  .document: interface document (on ftp) updated
  .document: The RTOSS'94 paper describes the stand-alone real-time
   micro-kernel for embedded application running on a VME SPARCengine 1E
   (see rtoss94.ps.Z on ftp site).

The following features are included in the current implementation:
-from POSIX.4a:
  .thread management: initializing, creating, joining, exiting, and
   destroying threads
  .synchronization: mutual exclusion, condition variables
  .thread-specific data
  .thread priority scheduling: priority management, preemptive
   priority scheduling (FIFO, RR),
   mutex priority ceilings through stack resource policy (SRP)
  .signals: signal handlers, synchronous and asynchronous wait for
   signals, masking and sending of signals, sleep, long jumps
  .cancellation: cleanup handlers, asynchronous, synchronous, and
   disabled interruptability.
-from POSIX.4:
  .timers: nanosleep, read clock, priority scheduling bounds
-from POSIX.1:
  .synchronous I/O for threads (I/O only blocks current thread, not process)
-others:
  .perverted scheduling for debugging (MUT_SWITCH, RR_SWITCH, RAND_SWITCH)
  .stack overflow check causes signal (optional STACK_CHECK)
  .graceful handling of stack overflow (optional SIGNAL_STACK)
  .repeated inclusion of header files prevented

The support is currently being extended to include:
-from POSIX.4a:
  .mutex priority inheritance / priority ceiling emulation protocol
  .reentrant functions
  .process control: fork, wait, waitpid
   (The above functions are not supported for threads. Their semantics
    is whatever UNIX semantics for processes is. Consequently, a fork
    will fork another process with ALL threads being duplicated, not
    just the executing thread as required by POSIX.4a.
    The functions exec and _exit behave as required without any
    change, i.e. the UNIX process level semantics for these functions
    is also adequate for threads.)
-from POSIX.4:
  .asynchronous I/O for threads
  .asynchronous timer objects
-other:
  .heap memory pools

The current scheduling policies are strict priority scheduling
(according to POSIX.4a FIFO scheduling) which preempts when signals
are caught or round-robin (RR scheduling) which changes context to
another thread of the same priority after a time-slice of 20msec.
Besides asynchronous delivery of signals, context switches only occur
where required by the priority policy, e.g. when resources (mutexes)
are locked etc.

The current implementation has been tested and used as a base to
implement our own (new) runtime-system for an Ada compiler (Verdix).
But we do not make any claims about the completeness or correctness of
this implementation.

(C)OPYRIGHT NOTICE:

   Copyright (C) 1992, the Florida State University
   Distributed by the Florida State University under the terms of the
   GNU Library General Public License.

This file is part of Pthreads.

Pthreads is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation (version 2).

Pthreads is distributed "AS IS" in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with Pthreads; see the file COPYING.  If not, write
to the Free Software Foundation, 675 Mass Ave, Cambridge,
MA 02139, USA.

Report problems and direct all questions to:

  pthreads-bugs@ada.cs.fsu.edu