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diff --git a/win32/contrib/pthreads/FAQ b/win32/contrib/pthreads/FAQ deleted file mode 100644 index 44ae761fe..000000000 --- a/win32/contrib/pthreads/FAQ +++ /dev/null @@ -1,390 +0,0 @@ - =========================================
- PTHREADS-WIN32 Frequently Asked Questions
- =========================================
-
-INDEX
------
-
-Q 1 Should I use Cygwin or Mingw32 as a development environment?
-
-Q 2 Now that pthreads-win32 builds under Mingw32, why do I get
- memory access violations?
-
-Q 3 How do I use pthread.dll for Win32 (Visual C++ 5.0)
-
-Q 4 Cancelation doesn't work for me, why?
-
-Q 5 Thread won't block after two calls to mutex_lock
-
-Q 6 How do I generate pthreadGCE.dll and libpthreadw32.a for use with Mingw32?
-
-=============================================================================
-
-Q 1 Should I use Cygwin or Mingw32 as a development environment?
----
-
-A 1
----
-Important: see Q2 also.
-
-In short, use Mingw32 with the MSVCRT library to build applications that use
-the DLL. Cygwin's own internal support for POSIX threads is growing. Consult
-that project's documentation for more information.
-
-Date: Mon, 07 Dec 1998 15:11:37 +0100
-From: Anders Norlander <anorland@hem2.passagen.se>
-To: Ross Johnson <rpj@ise.canberra.edu.au>
-Cc: pthreads-win32 <pthreads-win32@air.net.au>
-Subject: Re: pthreads-win32: TryEnterCriticalSection patch (fwd)
-
-Ross Johnson wrote:
->
-> Anders,
->
-> You said you're using GCC. Is that from cygwin32 or mingw32? What is your
-> environment (so I can perhaps help other people out)? We have problems
-> with cygwin32 et al that have been built on Win95. They're missing
-> _{begin,end}threadex.
-
-Ross,
-
-I use mingw32 when compiling pthreads-win32, but unlike most people I
-use MSVCRT as the C library instead of CRTDLL. For those that don't
-feel like configuring and building the necessary components themselves,
-Mumit Khan has released an add on for mingw32 to make it use MSVCRT40.
-It is available at his ftp site, follow the minw32 links at
-http://www.xraylith.wisc.edu/~khan/software/gnu-win32/
-
-For cygwin it is a completely different matter. I suppose
-pthreads-win32 uses _beginthreadex and _endthreadex because the Win32
-docs say that programs calling functions in the C library should not
-use CreateThread and ExitThread. However, this applies only to
-Microsoft's (and possibly others) multithreaded C libraries that need
-to keep track of per thread data, it does not apply to cygwin.
-This code solves the problem:
-
-/* Check for old and new versions of cygwin */
-#if defined(__CYGWIN32__) || defined(__CYGWIN__)
-/* Macro uses args so we can cast start_proc to LPTHREAD_START_ROUTINE
- in order to avoid warnings because of return type */
-#define _beginthreadex(security, stack_size, start_proc, arg, flags,
-pid) \
-CreateThread(security, stack_size, (LPTHREAD_START_ROUTINE) start_proc,
-\
- arg, flags, pid)
-#define _endthreadex ExitThread
-#endif
-
-I would be extremely careful using threads with cygwin, since it is
-not (yet) threadsafe.
-
-Regards,
-Anders
-
-------------------------------------------------------------------------------
-
-Q 2 Now that pthreads-win32 builds under Mingw32, why do I get
---- memory access violations (segfaults)?
-
-A 2
----
-Note: issue resolved.
-The latest Mingw32 package has thread-safe exception handling.
-Make sure you also read A 6 below to get a fully working build.
-
-
-The following email exchange describes the problem. Until this issue
-is resolved people without the Microsoft compiler can obtain the current
-MSVC prebuilt DLL (pthread.{dll,lib,h}) at:
-
-ftp://sources.redhat.com/pub/pthreads-win32/dll-latest
-
-Date: Wed, 10 Feb 1999 13:21:01 -0000
-From: "Ruland, Kevin" <Kevin.Ruland@anheuser-busch.com>
-Reply-To: POSIX threads on Win32 <pthreads-win32@air.net.au>
-To: 'POSIX threads on Win32' <pthreads-win32@air.net.au>
-Subject: Mingw32 exceptions not thread safe.
-
-Hello everyone.
-
-I asked Mumit Khan, maintainer of egcs for mingw and assorted guru, about
-the Known Problem listed below.
-
-> Known problems
-> --------------
->
-> There is an unresolved bug which shows up as a segmentation fault
-> (memory access violation) when the library is built using g++. Build
-> the test program "eyal1.c" and run with an argument of "2" or
-> greater. The argument is the number of threads to run, excluding the
-> main thread, so the bug appears with 2 or more worker threads.
->
-> Kevin Ruland has traced the exception to the try/catch blocks in
-> ptw32_threadStart().
->
-
-The official word is:
-
-<Quote Mumit Khan [khan@xraylith.wisc.edu]>
-EGCS-1.1.1 for win32 (either cygwin or crtdll/msvc runtimes) do not have
-thread-safe exception support.
-
-For Cygwin, it'll happen when Cygwin runtime has mature thread safety and
-pthread is fully integrated. Then it's just a matter of rebuilding GCC (or
-just libgcc in this) with thread safe EH support.
-
-For Mingw crtdll/msvc, someone needs to write the thread-wrapper for win32
-threads. Anyone who knows win32 threads should be able to do this without
-much trouble at all. It's low on my priority list, so unless someone else
-volunteers, it'll have to wait.
-<\Quote>
-
-Kevin
-
-------------------------------------------------------------------------------
-
-Q 3 How do I use pthread.dll for Win32 (Visual C++ 5.0)
----
-
-A 3
----
->
-> I'm a "rookie" when it comes to your pthread implementation. I'm currently
-> desperately trying to install the prebuilt .dll file into my MSVC compiler.
-> Could you please provide me with explicit instructions on how to do this (or
-> direct me to a resource(s) where I can acquire such information)?
->
-> Thank you,
->
-
-You should have a .dll, .lib, .def, and three .h files.
-
-The .dll can go in any directory listed in your PATH environment
-variable, so putting it into C:\WINDOWS should work.
-
-The .lib file can go in any directory listed in your LIB environment
-variable.
-
-The .h files can go in any directory listed in your INCLUDE
-environment variable.
-
-Or you might prefer to put the .lib and .h files into a new directory
-and add its path to LIB and INCLUDE. You can probably do this easiest
-by editing the file:-
-
-C:\Program Files\DevStudio\vc\bin\vcvars32.bat
-
-The .def file isn't used by anything in the pre-compiled version but
-is included for information.
-
-Cheers.
-Ross
-
-------------------------------------------------------------------------------
-
-Q 4 Cancelation doesn't work for me, why?
----
-
-A 4
----
-> I'm investigating a problem regarding thread cancelation. The thread I want
-> to cancel has PTHREAD_CANCEL_ASYNCHRONOUS, however, this piece of code
-> blocks on the join():
->
-> if ((retv = Pthread_cancel( recvThread )) == 0)
-> {
-> retv = Pthread_join( recvThread, 0 );
-> }
->
-> Pthread_* are just macro's; they call pthread_*.
->
-> The thread recvThread seems to block on a select() call. It doesn't get
-> cancelled.
->
-> Two questions:
->
-> 1) is this normal behaviour?
->
-> 2) if not, how does the cancel mechanism work? I'm not very familliar to
-> win32 programming, so I don't really understand how the *Event() family of
-> calls work.
-
-Async cancelation should be in versions post snapshot-1999-11-02
-of pthreads-win32 (currently only for x86 architectures).
-
-The answer to your first question is, normal POSIX behaviour would
-be to asynchronously cancel the thread. However, even that doesn't
-guarantee cancelation as the standard only says it should be
-cancelled as soon as possible.
-
-However ...
-
-Snapshot 99-11-02 or earlier only partially supports asynchronous cancellation.
-Snapshots since then simulate async cancelation by poking the address of
-a cancelation routine into the PC of the threads context. This requires
-the thread to be resumed in some way for the cancelation to actually
-proceed. This is not true async cancelation, but it is as close as we've
-been able to get to it.
-
-If the thread you're trying to cancel is blocked (for instance, it could be
-waiting for data from the network), it will only get cancelled when it unblocks
-(when the data arrives). Unfortunately, there is no way to do so from
-outside the thread.
-
-Using deferred cancelation would normally be the way to go, however,
-even though the POSIX threads standard lists a number of C library
-functions that are defined as deferred cancelation points, there is
-no hookup between those which are provided by Windows and the
-pthreads-win32 library.
-
-Incidently, it's worth noting for code portability that the POSIX
-threads standard list doesn't include "select" because (as I read in
-Butenhof) it isn't part of POSIX.
-
-Effectively, the only cancelation points that pthreads-win32 can
-recognise are those the library implements itself, ie.
-
- pthread_testcancel
- pthread_cond_wait
- pthread_cond_timedwait
- pthread_join
- sem_wait
- pthread_delay_np
-
-Pthreads-win32 also provides two functions that allow you to create
-cancelation points within your application, but only for cases where
-a thread is going to block on a Win32 handle. These are:
-
- pthreadCancelableWait(HANDLE waitHandle) /* Infinite wait */
-
- pthreadCancelableTimedWait(HANDLE waitHandle, DWORD timeout)
-
-Regards.
-Ross
-
-------------------------------------------------------------------------------
-
-Q 5 Thread won't block after two calls to mutex_lock
----
-
-A 5
----
-> i was testing this pthread for win32 in my prog.
-> when i checked if it was blocking mutex_lock calls, i was surprised when it
-> didnt lock
->
-> pthread_mutex_t DBlock;
->
-> pthread_mutex_init( &DBlock, NULL );
-> pthread_mutex_lock( &DBlock );
-> pthread_mutex_lock( &DBlock );
->
-> ^^ these two calls didnt block
-
-POSIX leaves the result "undefined" for a thread that tries
-to recursively lock the same mutex (one that it owns already).
-That means the actual semantics are left up to the
-implementation, but should not be relied upon for code that
-will be ported to different POSIX threads implementations.
-
-In the pthreads-win32 implementation a thread won't deadlock
-itself by relocking the mutex. Subsequent calls to
-pthread_mutex_lock() as in your example above increment
-the lock count but the thread continues on. Consequently,
-the thread must ensure that it unlocks the mutex once for
-each lock operation. That is, pthreads-win32 mutexes are
-always recursive.
-
-You may want to look at the other synchronisation devices
-available in the library, such as condition variables or
-read-write locks.
-
-Ross
-
-------------------------------------------------------------------------------
-
-Q 6 How do I generate pthreadGCE.dll and libpthreadw32.a for use with Mingw32?
----
-
-A 6
----
-Once you've followed Thomas Pfaff's instructions below to fix
-Mingw32, then you can simply run "make" to build the library and dll.
-
-
-From - Sat Dec 9 22:56:10 2000
-From: "Thomas Pfaff" <tpfaff@gmx.net>
-To: <mingw-users@lists.sourceforge.net>, <pthreads-win32@sources.redhat.com>
-Subject: mingw32 DLLs, threads and exceptions HOWTO
-Date: Thu, 7 Dec 2000 11:12:43 +0100
-
-Dear all,
-
-this is a summary that should help users to have thread safe exception
-handling over DLL exported functions.
-If you don't care about c++ exceptions you can stop reading here.
-
-The first time i struggled with c++ exceptions was when i tried to throw an
-exception in a dll exported function where the exception handler resides in
-the program module.
-Instead of catching the exception the program stopped with an abnormal
-termination.
-The reason was that the exception code is in libgcc.a. Since this is a
-static library the code and some static variables are both in the dll and in
-the program module, each module runs in its own context.
-It was Franco Bez that pointed me in the right direction, that is convert
-libgcc.a into a dll.
-
-That done i tried to build the pthreads-win32 library, but some tests failed
-with an access violation. Due to the fact that the dll was not build
-was -mthreads support, eh_context_static instead of eh_context_specific (the
-mthreads version) was used for exception handling.
-I did a rebuild of the gcc dll with -mthreads, now all tests are passed
-(except a nonportable exception test that relies on a MSVC feature).
-
-To build the gcc dll i did the following steps.
-
-1. create a temporary directory libgcc
-2. copy libgcc.a from gcc-2.95.2\lib\gcc-lib\i386-mingw32\gcc-2.95.2 to that
-directory
-3. ar -x libgcc.a
-4. create a directory tmp and move __main.o, _exit.o and __dummy.o in that
-directory
-5. build the dll
-gcc -shared -mthreads -o gcc.dll *.o
-strip gcc.dll
-Move this dll into your gcc\bin directory
-6. Move _chkstk.o and frame.o to the tmp directory, otherwise you break the
-builtin alloca.
-7. Build the import library libgcc.a
-dllwrap --export-all --dllname=gcc.dll --output-def=libgcc.def --output-lib=
-libgcc.a *.o
-ar -q libgcc.a tmp/*.o
-strip --strip-debug libgcc.a
-ranlib libgcc.a
-8. save your old libgcc.a, copy the new libgcc.a into
-gcc-2.95.2\lib\gcc-lib\i386-mingw32\gcc-2.95.2
-
-I am using gcc-2.95.2-1 with Mumits patched binutils-19990818-1and msvcrt
-runtime-2000-03-27.
-I don't know if this is still required with the current binutils and gcc
-since i have seen no sources until now.
-
-I believe that these steps are at least necessary if you are trying to use
-the pthreads-win32 library (which is required if you want to use gtk+ on
-win32).
-They will make mingw32 a real replacement for MSVC (at least for me).
-
-What is left:
-
-1. Include the mingwm10.dll function into the gcc.dll to have only one dll
-left.
-2. make -mthreads and -fnative-struct default compiler options.
-3. convert libstdc++ to a dll by adding the declspec dllexport and dllimport
-to every class definition.
-
-Regards,
- Thomas
-
-------------------------------------------------------------------------------
-
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