[ViewVC] Contents of: cvs/IO-AIO/Changes

Revision history for IO::AIO

TODO: better autoconf.pm that can return LIBS etc.
TODO: aio_cptree/mvtree
TODO: reduce condvar fairness: schedule hot-cache-threads first?
TODO: splice/tee/vmsplice/sync_file_range? (http://kerneltrap.org/node/6505 http://lwn.net/Articles/178199/)
TODO: aio_fcntl, at least for file-locking

3.03
        - (libeio) correctly call pthread_attr_destroy ().
        - (libeio) work around broken bsd headers once more.
        - reduce shared library size again by not including wrappers.
        - max_outstanding could cause poll to enter a busy-waiting loop.
        - document the new IO::AIO::poll_cb result value.

3.02 Mon May 12 02:32:02 CEST 2008
        - fix a memory leak on aio_readlink.
        - bring back working fchmod.
        - nop and busy now set result to 0.
        - set errno to ENOMEM when allocation fails.

3.01 Sun May 11 03:07:03 CEST 2008
        - (libeio) make it compile on systems without readahead or readdir_r.
        - (libeio) improve configure check for readahead availability.
        - do not try to link against -lrt.
        - use a separate configure script for IO::AIO (not the libeio one).

3.0  Sun May 11 00:57:14 CEST 2008
        - added bin/treescan to the distribution.
        - switched to using libeio.
        - LOTS OF INCOMPATIBLE CHANGES:
          - remove signal functionality, it is not worth the effort.
          - max_outstanding no longer returns the previous number of requests.
          - poll_cb no longer returns number of requests.

2.62 Sat Apr 26 13:59:33 CEST 2008
        - port to solaris perls configured for old posix
          (analysed by Jost Krieger).
        - keep a reference to the perl filehandle object in aio_close,
          so it doesn't get closed prematurely, leading to ugly races.

2.61 Wed Apr 16 18:45:02 CEST 2008
        - fix treescan output duplication and improve output ordering.
          also display files given on the commandline.
        - use a different algorithm for aio_close that is faster
          and probably has even lower chances of blocking.
        - do our own stack memory management for threads - linux
          allocates outrageous amounts of VM (not so bad unless you
          use mlockall...), which severely limits the number of threads
          on 32-bit arches: stack size is the larger of PTHREAD_STACK_MIN
          and 4096 * sizeof (long) (usually this is 16..64k).

2.6  Sun Mar 30 08:28:11 CEST 2008
        - added aio_sync.
        - added aio_pathsync.
        - fix prototypes of (void) functions.

2.51 Sat Oct  6 16:04:54 CEST 2007
        - perlio isn't generally threadsafe, so aio_close could not work reliably.
          aio_close now tries a safe hack that might not be that asynchronous
          (see the manpage for details).
        - discard callback return values as to not grow the stack endlessly
          when poll_cb handles many requests without returning.
        - minor code cleanups.

2.5  Thu Oct  4 14:49:08 CEST 2007
        - replaced _fd2fh with faster xs code.
        - aio_close will now try to do "the right thing" and thus might
          work sensibly for the very first time.

2.41 Mon Sep 24 21:28:21 CEST 2007
        - after fork, invest some work to make sure that the poll_fileno
          stays stable (by dup2'ing the new fd over the old one), to make
          it easier for programs/libs that don't control their forking
          behaviour and cannot recreate their watchers.

2.4  Sun Aug  5 18:44:22 CEST 2007
        - add aio_truncate, aio_chmod, aio_chown, aio_utime (linux
          successfully demonstrated that you can block on futimes...).
        - allow undef as fileoffset for aio_read/write and use read/write(2)
          internally (useful for sockets or O_APPEND handles).
        - allow undef for length in aio_write.
        - negative dataoffsets work as expected now in aio_read/aio_write.
        - use NV instead of UV for 32 bit perls and file offsets, as NVs
          have a larger range then.
        - shared code between BDB and IO::AIO.
        - aio_busy was completely broken. now fixed.
        - readahead emulation now returns something.
        - correctly set errno to ENOSYS on unimplemented functions
          (should never happen, though).
        - large changes to make it partially compile and run on win32,
          but win32 lacks too much functionality, and perl overrides way
          too many functions with crashing versions.

2.33 Tue Jan 23 23:55:41 CET 2007
        - fix install path (Andreas J. Koenig).

2.32 Mon Jan 22 16:56:23 CET 2007
        - added aio_rmtree.
        - wow, aio_mkdir was missing.
        - aio_load did return undef on error, not -1.
        - use prefixexp not prefix in autoconf.pm
          (suggested by ... rt.cpan.org unreachable).
        - avoid installing autoconf.pm.

2.31 Sat Jan  6 03:46:02 CET 2007
        - added aio_load.

2.3  Sat Dec 23 05:48:07 CET 2006
        - fix off-by-one bug in aio_read, causing memory corruption
          or crashes.

2.21  Fri Dec 22 05:03:38 CET 2006
        - minor doc updates.
        - minor cleanups.
        - IO::AIO::poll returns request count.
        - undocumented and unfinished async-signal-reporting.

2.2  Tue Oct 31 00:31:00 CET 2006
        - minor doc updates.
        - added aio_readlink.
        - properly zero-terminate aio_read buffer.
        - fix aio_read/write with nonzero dataoffset.
        - reduced size of aio request structure.
        - better diagnostics when pathnames etc. are not byte-encoded;
          do not leak request in that case, either.

2.1  Sun Oct 29 02:01:57 CET 2006
        - INCOMPATIBLE CHANGE: replace IO::AIO::poll_some by
          IO::AIO::max_poll_reqs and IO::AIO::max_poll_time.
        - fix a bug in aio_move where it would fail everytime
          it would have to copy files manually.
        - doc updates.
        - start threads only on (very low) demand.
        - end superfluous threads automatically after 10s idling.
        - add IO::AIO::max_idle to control this.
        - some tuning applied to random places.
        - add aio_mknod.

2.0  Thu Oct 26 18:27:58 CEST 2006
        - minor incompatibility: max_outstanding semantics have changed.
        - major rewrite, consider all functionality EXPERIMENTAL.
        - aio requests can be cancelled.
        - callbacks can be (re-)set later.
        - aio requests can choose between 9 priorities.
        - add aio_group: aio requests can be grouped
          into composite requests.
        - generator interface for groups.
        - add IO::AIO::poll_some.
        - major documentation improvements.
        - very minor bugfixes.
        - add aio_nop for dummy requests.
        - add aio_busy mainly for benchmarking and debugging.
        - use "fast" mutexes on linux.
        - use dynamic (and larger) buffers instead of
          putting them onto the stack.
        - optimise x86 and amd64 a bit.
        - better error checking when ENOMEM.
        - hopefully fix mem and dirp leaks on fork.
        - warn about broken perl malloc.
        - compiles on cygwin (but pread is broken on cygwin
          which is not detected by autoconf, so you have to
          edit autoconf/config.h yourself to enable emulation).

1.8  Sat Jun 24 22:20:44 CEST 2006
        - add and/or document aio_rename, aio_link, aio_symlink and aio_move.

1.73 Wed Mar  1 22:49:32 CET 2006
        - codename "jost"
        - AIX/Solaris(?) aren't being helpful again, hardcode a value
          for NAME_MAX and drive with your eyes closed (reported by
          wcooley@nakedape.cc).

1.72 Thu Feb  2 00:40:44 CET 2006
        - another minor bug in aio_scandir, again, the callback was called
          twice when the directory can't be stat'ed.

1.71 Mon Dec 26 20:20:03 CET 2005
        - grr, another minor bug in aio_scandir, this time resulting
          in a runtime error.

1.7  Mon Dec 26 19:29:48 CET 2005
        - aio_scandir errornously called callback twice in some cases.
        - added AnyEvent example.

1.61 Wed Sep  7 19:40:42 CEST 2005
        - no longer include $Config{libs}, as distros include too much
          garbage in there that is not installed on typical systems
          (for example, debian links perl against -lgdbm and many more
          libraries despite perl not needing it, slowing down startup and
          wasting memory).

1.6  Tue Aug 30 17:44:44 CEST 2005
        - added aio_readdir, aio_scandir.
        - added aio_sendfile, including sendfile emulation when sendfile
          isn't available. Linux, FreeBSD and HP-UX might work (sendfilev
          support is unavailable on my solaris 8 machine, but preliminary
          code is there. What's lacking is configury stuff and testing...).

1.5  Sat Aug 20 02:32:19 CEST 2005
        - create the aio threads on demand only (good after forking).
        - somebody nagged about C89 compatibility, so this release should
          be C89 compatible, but no guarantees for future ones.
        - abort when the configure script fails.

1.4  Wed Aug 17 08:07:27 CEST 2005
        - forgot to recreate the pipe after forking, this could cause
          deadlocks.

1.3  Wed Aug 17 07:25:54 CEST 2005
        - properly propagate exceptions from callbacks, instead of silently
          eating them.
        - use a different fork algorithm that avoids recursive callback
          invocations and reduces fork latency in busy processes.
        - fix a bug where the buffer scalar in aio_read got assigned the wrong
          length after reading.
        - fix a bug where the child would process some outstanding requests
          from the parent.
        - make a copy of the callback scalar, to avoid some very uncommon
          (but valid) usages where the callback scalar changes.
        - the callback was never freed in aio_read/aio_write.
        - aio_read/aio_write will now set the readonly flag on the data
          scalar for better error reporting.

1.2  Wed Aug 17 01:22:58 CEST 2005
        - verified on cygwin, linux/amd64+ia32+alpha, solaris.
        - use SvPVbyte for filenames now. You *need* to encode your strings to
          the external filename encoding first.
        - fix the bug where filehandles could leak (again).
        - clarify freebsd situation: make it work and tell me how, or go away
          with your underdocumented, broken and outdated OS.
        - fork'ing should now be officially supported (where linux and
          posix contradict each other, I followed posix).
        - only call read() once per poll, not twice (speedup).
        - new functions: aio_rmdir, aio_symlink.
        - force callback arguments to be undef or a reference, for better
          error catching.

1.1  Sun Aug  7 05:27:23 CEST 2005
        - added configure script to detect availability of some calls.
          (imperfect, as we cannot detect things like -lrt due to missing
          feedback yet).
        - emulate fdatasync via fsync, pread/pwrite via unsafe read/write
          and readahead via manual reading on platforms lacking those.
        - ported t/03_errors.t+framework by Brad Fitzpatrick
          from Linux::AIO.
        - removed XOPEN_SOURCE because stupid solaris 9 doesn't
          compile with it enabled. Probably breaks others. Oh well.
        - try to be more careful with errno on non-threaded perls.
        - cygwins perl insisted on a matching open mode when morphing
          the fd to an fh.
        - convert sv's to "byte" encoding in aio_read/aio_write. Might
          do that for pathnames, too, in the future, so make sure you
          properly encode your pathnames.

1.0  Fri Jul 22 10:43:30 CEST 2005
        - aio_open did not reliably deliver (open) filehandles.
        - all aio_*-functions keep a reference to the filehandle so
          it doesn't go away while the aio requests is working on it.
        - disable warnings in AIO.pm.

0.9  Wed Jul 20 23:55:04 CEST 2005
        - allow recursive calls to poll_cb, use less locking calls, too.
        - fix the Gtk2-example in the SYNOPSIS.
        - use pread/pwrite not pread64/pwrite64. this was simply a leftover
          from Linux::AIO.
          (found by compiling on cygwin. Unfortunately, cygwin declares but
          does not implement pread/pwrite).
        - only include <sys/syscall.h> on linux.

0.5  Tue Jul 12 13:03:09 CEST 2005
        - removed #include <endian.h>, it's not portable, and we don't
          need it anyway.
        - link against -lrt, as it might contain goodies such as fdatasync,
          and often aio_read, which we do not use yet, but it shouldn't hurt.

0.4  Mon Jul 11 05:28:25 CEST 2005
        - added IO::AIO::flush, IO::AIO::poll.
        - make callback argument optional for all calls.

0.3  Mon Jul 11 01:42:37 CEST 2005
        - restructured manpage.
        - added SYNOPSIS with examples for Event, Glib, Tk.
        - remove explicit context support so I don't have to maintain
          it for threaded perls (i.e. it should work now :).

0.2  Sun Jul 10 22:57:12 CEST 2005
        - return immediately from poll_wait if nreqs==0.
        - get rid of the request pipe and use faster thread-thread
          communications for most requests and responses.

0.1
        - cloned from Linux::AIO, which is very similar.

Revision:	1.156
Committed:	Thu May 29 03:20:40 2008 UTC (16 years ago) by root
Branch:	MAIN
Changes since 1.155:	+3 -0 lines
Log Message:	* empty log message *
#	Content
1	Revision history for IO::AIO
2
3	TODO: better autoconf.pm that can return LIBS etc.
4	TODO: aio_cptree/mvtree
5	TODO: reduce condvar fairness: schedule hot-cache-threads first?
6	TODO: splice/tee/vmsplice/sync_file_range? (http://kerneltrap.org/node/6505 http://lwn.net/Articles/178199/)
7	TODO: aio_fcntl, at least for file-locking
8
9	3.03
10	- (libeio) correctly call pthread_attr_destroy ().
11	- (libeio) work around broken bsd headers once more.
12	- reduce shared library size again by not including wrappers.
13	- max_outstanding could cause poll to enter a busy-waiting loop.
14	- document the new IO::AIO::poll_cb result value.
15
16	3.02 Mon May 12 02:32:02 CEST 2008
17	- fix a memory leak on aio_readlink.
18	- bring back working fchmod.
19	- nop and busy now set result to 0.
20	- set errno to ENOMEM when allocation fails.
21
22	3.01 Sun May 11 03:07:03 CEST 2008
23	- (libeio) make it compile on systems without readahead or readdir_r.
24	- (libeio) improve configure check for readahead availability.
25	- do not try to link against -lrt.
26	- use a separate configure script for IO::AIO (not the libeio one).
27
28	3.0 Sun May 11 00:57:14 CEST 2008
29	- added bin/treescan to the distribution.
30	- switched to using libeio.
31	- LOTS OF INCOMPATIBLE CHANGES:
32	- remove signal functionality, it is not worth the effort.
33	- max_outstanding no longer returns the previous number of requests.
34	- poll_cb no longer returns number of requests.
35
36	2.62 Sat Apr 26 13:59:33 CEST 2008
37	- port to solaris perls configured for old posix
38	(analysed by Jost Krieger).
39	- keep a reference to the perl filehandle object in aio_close,
40	so it doesn't get closed prematurely, leading to ugly races.
41
42	2.61 Wed Apr 16 18:45:02 CEST 2008
43	- fix treescan output duplication and improve output ordering.
44	also display files given on the commandline.
45	- use a different algorithm for aio_close that is faster
46	and probably has even lower chances of blocking.
47	- do our own stack memory management for threads - linux
48	allocates outrageous amounts of VM (not so bad unless you
49	use mlockall...), which severely limits the number of threads
50	on 32-bit arches: stack size is the larger of PTHREAD_STACK_MIN
51	and 4096 * sizeof (long) (usually this is 16..64k).
52
53	2.6 Sun Mar 30 08:28:11 CEST 2008
54	- added aio_sync.
55	- added aio_pathsync.
56	- fix prototypes of (void) functions.
57
58	2.51 Sat Oct 6 16:04:54 CEST 2007
59	- perlio isn't generally threadsafe, so aio_close could not work reliably.
60	aio_close now tries a safe hack that might not be that asynchronous
61	(see the manpage for details).
62	- discard callback return values as to not grow the stack endlessly
63	when poll_cb handles many requests without returning.
64	- minor code cleanups.
65
66	2.5 Thu Oct 4 14:49:08 CEST 2007
67	- replaced _fd2fh with faster xs code.
68	- aio_close will now try to do "the right thing" and thus might
69	work sensibly for the very first time.
70
71	2.41 Mon Sep 24 21:28:21 CEST 2007
72	- after fork, invest some work to make sure that the poll_fileno
73	stays stable (by dup2'ing the new fd over the old one), to make
74	it easier for programs/libs that don't control their forking
75	behaviour and cannot recreate their watchers.
76
77	2.4 Sun Aug 5 18:44:22 CEST 2007
78	- add aio_truncate, aio_chmod, aio_chown, aio_utime (linux
79	successfully demonstrated that you can block on futimes...).
80	- allow undef as fileoffset for aio_read/write and use read/write(2)
81	internally (useful for sockets or O_APPEND handles).
82	- allow undef for length in aio_write.
83	- negative dataoffsets work as expected now in aio_read/aio_write.
84	- use NV instead of UV for 32 bit perls and file offsets, as NVs
85	have a larger range then.
86	- shared code between BDB and IO::AIO.
87	- aio_busy was completely broken. now fixed.
88	- readahead emulation now returns something.
89	- correctly set errno to ENOSYS on unimplemented functions
90	(should never happen, though).
91	- large changes to make it partially compile and run on win32,
92	but win32 lacks too much functionality, and perl overrides way
93	too many functions with crashing versions.
94
95	2.33 Tue Jan 23 23:55:41 CET 2007
96	- fix install path (Andreas J. Koenig).
97
98	2.32 Mon Jan 22 16:56:23 CET 2007
99	- added aio_rmtree.
100	- wow, aio_mkdir was missing.
101	- aio_load did return undef on error, not -1.
102	- use prefixexp not prefix in autoconf.pm
103	(suggested by ... rt.cpan.org unreachable).
104	- avoid installing autoconf.pm.
105
106	2.31 Sat Jan 6 03:46:02 CET 2007
107	- added aio_load.
108
109	2.3 Sat Dec 23 05:48:07 CET 2006
110	- fix off-by-one bug in aio_read, causing memory corruption
111	or crashes.
112
113	2.21 Fri Dec 22 05:03:38 CET 2006
114	- minor doc updates.
115	- minor cleanups.
116	- IO::AIO::poll returns request count.
117	- undocumented and unfinished async-signal-reporting.
118
119	2.2 Tue Oct 31 00:31:00 CET 2006
120	- minor doc updates.
121	- added aio_readlink.
122	- properly zero-terminate aio_read buffer.
123	- fix aio_read/write with nonzero dataoffset.
124	- reduced size of aio request structure.
125	- better diagnostics when pathnames etc. are not byte-encoded;
126	do not leak request in that case, either.
127
128	2.1 Sun Oct 29 02:01:57 CET 2006
129	- INCOMPATIBLE CHANGE: replace IO::AIO::poll_some by
130	IO::AIO::max_poll_reqs and IO::AIO::max_poll_time.
131	- fix a bug in aio_move where it would fail everytime
132	it would have to copy files manually.
133	- doc updates.
134	- start threads only on (very low) demand.
135	- end superfluous threads automatically after 10s idling.
136	- add IO::AIO::max_idle to control this.
137	- some tuning applied to random places.
138	- add aio_mknod.
139
140	2.0 Thu Oct 26 18:27:58 CEST 2006
141	- minor incompatibility: max_outstanding semantics have changed.
142	- major rewrite, consider all functionality EXPERIMENTAL.
143	- aio requests can be cancelled.
144	- callbacks can be (re-)set later.
145	- aio requests can choose between 9 priorities.
146	- add aio_group: aio requests can be grouped
147	into composite requests.
148	- generator interface for groups.
149	- add IO::AIO::poll_some.
150	- major documentation improvements.
151	- very minor bugfixes.
152	- add aio_nop for dummy requests.
153	- add aio_busy mainly for benchmarking and debugging.
154	- use "fast" mutexes on linux.
155	- use dynamic (and larger) buffers instead of
156	putting them onto the stack.
157	- optimise x86 and amd64 a bit.
158	- better error checking when ENOMEM.
159	- hopefully fix mem and dirp leaks on fork.
160	- warn about broken perl malloc.
161	- compiles on cygwin (but pread is broken on cygwin
162	which is not detected by autoconf, so you have to
163	edit autoconf/config.h yourself to enable emulation).
164
165	1.8 Sat Jun 24 22:20:44 CEST 2006
166	- add and/or document aio_rename, aio_link, aio_symlink and aio_move.
167
168	1.73 Wed Mar 1 22:49:32 CET 2006
169	- codename "jost"
170	- AIX/Solaris(?) aren't being helpful again, hardcode a value
171	for NAME_MAX and drive with your eyes closed (reported by
172	wcooley@nakedape.cc).
173
174	1.72 Thu Feb 2 00:40:44 CET 2006
175	- another minor bug in aio_scandir, again, the callback was called
176	twice when the directory can't be stat'ed.
177
178	1.71 Mon Dec 26 20:20:03 CET 2005
179	- grr, another minor bug in aio_scandir, this time resulting
180	in a runtime error.
181
182	1.7 Mon Dec 26 19:29:48 CET 2005
183	- aio_scandir errornously called callback twice in some cases.
184	- added AnyEvent example.
185
186	1.61 Wed Sep 7 19:40:42 CEST 2005
187	- no longer include $Config{libs}, as distros include too much
188	garbage in there that is not installed on typical systems
189	(for example, debian links perl against -lgdbm and many more
190	libraries despite perl not needing it, slowing down startup and
191	wasting memory).
192
193	1.6 Tue Aug 30 17:44:44 CEST 2005
194	- added aio_readdir, aio_scandir.
195	- added aio_sendfile, including sendfile emulation when sendfile
196	isn't available. Linux, FreeBSD and HP-UX might work (sendfilev
197	support is unavailable on my solaris 8 machine, but preliminary
198	code is there. What's lacking is configury stuff and testing...).
199
200	1.5 Sat Aug 20 02:32:19 CEST 2005
201	- create the aio threads on demand only (good after forking).
202	- somebody nagged about C89 compatibility, so this release should
203	be C89 compatible, but no guarantees for future ones.
204	- abort when the configure script fails.
205
206	1.4 Wed Aug 17 08:07:27 CEST 2005
207	- forgot to recreate the pipe after forking, this could cause
208	deadlocks.
209
210	1.3 Wed Aug 17 07:25:54 CEST 2005
211	- properly propagate exceptions from callbacks, instead of silently
212	eating them.
213	- use a different fork algorithm that avoids recursive callback
214	invocations and reduces fork latency in busy processes.
215	- fix a bug where the buffer scalar in aio_read got assigned the wrong
216	length after reading.
217	- fix a bug where the child would process some outstanding requests
218	from the parent.
219	- make a copy of the callback scalar, to avoid some very uncommon
220	(but valid) usages where the callback scalar changes.
221	- the callback was never freed in aio_read/aio_write.
222	- aio_read/aio_write will now set the readonly flag on the data
223	scalar for better error reporting.
224
225	1.2 Wed Aug 17 01:22:58 CEST 2005
226	- verified on cygwin, linux/amd64+ia32+alpha, solaris.
227	- use SvPVbyte for filenames now. You need to encode your strings to
228	the external filename encoding first.
229	- fix the bug where filehandles could leak (again).
230	- clarify freebsd situation: make it work and tell me how, or go away
231	with your underdocumented, broken and outdated OS.
232	- fork'ing should now be officially supported (where linux and
233	posix contradict each other, I followed posix).
234	- only call read() once per poll, not twice (speedup).
235	- new functions: aio_rmdir, aio_symlink.
236	- force callback arguments to be undef or a reference, for better
237	error catching.
238
239	1.1 Sun Aug 7 05:27:23 CEST 2005
240	- added configure script to detect availability of some calls.
241	(imperfect, as we cannot detect things like -lrt due to missing
242	feedback yet).
243	- emulate fdatasync via fsync, pread/pwrite via unsafe read/write
244	and readahead via manual reading on platforms lacking those.
245	- ported t/03_errors.t+framework by Brad Fitzpatrick
246	from Linux::AIO.
247	- removed XOPEN_SOURCE because stupid solaris 9 doesn't
248	compile with it enabled. Probably breaks others. Oh well.
249	- try to be more careful with errno on non-threaded perls.
250	- cygwins perl insisted on a matching open mode when morphing
251	the fd to an fh.
252	- convert sv's to "byte" encoding in aio_read/aio_write. Might
253	do that for pathnames, too, in the future, so make sure you
254	properly encode your pathnames.
255
256	1.0 Fri Jul 22 10:43:30 CEST 2005
257	- aio_open did not reliably deliver (open) filehandles.
258	- all aio_*-functions keep a reference to the filehandle so
259	it doesn't go away while the aio requests is working on it.
260	- disable warnings in AIO.pm.
261
262	0.9 Wed Jul 20 23:55:04 CEST 2005
263	- allow recursive calls to poll_cb, use less locking calls, too.
264	- fix the Gtk2-example in the SYNOPSIS.
265	- use pread/pwrite not pread64/pwrite64. this was simply a leftover
266	from Linux::AIO.
267	(found by compiling on cygwin. Unfortunately, cygwin declares but
268	does not implement pread/pwrite).
269	- only include <sys/syscall.h> on linux.
270
271	0.5 Tue Jul 12 13:03:09 CEST 2005
272	- removed #include <endian.h>, it's not portable, and we don't
273	need it anyway.
274	- link against -lrt, as it might contain goodies such as fdatasync,
275	and often aio_read, which we do not use yet, but it shouldn't hurt.
276
277	0.4 Mon Jul 11 05:28:25 CEST 2005
278	- added IO::AIO::flush, IO::AIO::poll.
279	- make callback argument optional for all calls.
280
281	0.3 Mon Jul 11 01:42:37 CEST 2005
282	- restructured manpage.
283	- added SYNOPSIS with examples for Event, Glib, Tk.
284	- remove explicit context support so I don't have to maintain
285	it for threaded perls (i.e. it should work now :).
286
287	0.2 Sun Jul 10 22:57:12 CEST 2005
288	- return immediately from poll_wait if nreqs==0.
289	- get rid of the request pipe and use faster thread-thread
290	communications for most requests and responses.
291
292	0.1
293	- cloned from Linux::AIO, which is very similar.
294