IO 1.51
    * #20201 bump dist/IO to v1.51, due to PR 19663
    * [doc] Update IO::Handle synopsis. Add `my` to examples for better practice.
    * Update IO::File synopsis. Add `my` to examples for better practice.
    * Update IO::Dir synopsis. Add `my` to examples for better practice.
    * IO::Socket::UNIX: Add proper hyperlink in pod
    * IO::Socket::INET: Use proper hyperlink in pod
    * IO::Pipe: Use proper hyperlink in pod
    * IO::Handle: Use proper hyperlink in pod
    * Fix dist/IO/poll.h for mingw-w64 runtimes 9.0 and later

IO 1.50
   * Bump to 1.50 after cpantesters run.

IO 1.49_01
   * Update IO.xs to conform to ppport.h 3.68 recommendations

IO 1.49
   * Send bug reports to
   * dist/IO/IO.xs: Rmv defns that ppport.h supplies

IO 1.48
   * Fix for undefined warning in GH #18238

IO 1.47
   * Implement sync() for win32
   * Add missing quotes to IO::Socket::INET example

IO 1.46
   * style: Detabify indentation of the C code maintained by the core.
   * Update URLs

IO 1.45
  * Put IO::Socket constructor error messages in $IO::Socket::errstr as well
    as $@, to encourage better practices

IO 1.44
  * IO::Handle::error() now checks both the input and output stream
    for error.  This is an issue for sockets and character devices.  GH #6799
  * IO::Handle::clearerr() now clears the error on both input and
    output streams.

IO 1.43
  * only cache the protocol for sockets when one is supplied,
    otherwise protocol could return an incorrect protocol.  This means
    that on platforms that don't support SO_PROTOCOL (or don't support
    it for some socket types) protocol() can now return undef.

IO 1.42 - Jan 20 2020 - Todd Rinaldo
  * Point IO support to perl/perl5 not dual-life/IO

IO 1.41 - Jan 20 2020 - Todd Rinaldo
  * Switch pre-release testing to github actions.
  * Update MANIFEST with new test.

IO 1.41_50 -- Dec 16 2019 - Ricardo Signes
  * Loading IO is now threadsafe, avoiding the core bug reported as GH #14816.
    Implemented by converting getline() and getlines() to XS code.

IO 1.41 -- Dec 12 2019 - Ricardo Signes
  * import the latest from blead, so some changes may be in intermediate
    versions found only in releases of perl5
  * (perl #133936) make send() a bit saner
  * (perl #133936) document differences between IO::Socket::* and builtin
  * (perl #133936) ensure TO is honoured for UDP $sock->send()
  * Remove vestiges of mpeix support (removed in 5.17.x)
  * Documentation formatting fixes
  * Improve isolation of tests as they run

IO 1.38 -- Apr 19 2018 - Todd Rinaldo
  * Remove pre 5.8 logic from code base.
  * Bump all IO modules to 1.38 and set required Perl to 5.8.1
  * Fix for perl #125723
  * IO test: adjust require for non CORE perl
  * IO::Handle - fix precedence issue
  * Document IO::Select error detection
  * Rely on C89 <time.h>
  * (perl #130856) deal with unpack_sockaddr_un() croaking
  * Switch most open() calls to three-argument form.
  * (perl #129788) IO::Poll: fix memory leak
  * (perl #128095) check pack_sockaddr_un()'s return value
  * dist/: remove . from @INC when loading optional modules
  * Fix IO::Handle documentation mangled by a manually applied patch
  * Make IO::Poll->poll call _poll even with an empty fd array
  * Fix assertion when calling IO::Poll::_poll() with an empty fd array
  * Some BSD implementations might have <sys/poll.h> instead of <poll.h>.

IO 1.36 -- Jun 26 2015 (Not released to CPAN)
  * dist/IO/t/io_utf8argv.t: Generalize for non-ASCII platforms.
  * VMS does have fsync, so configure accordingly.
  * Skip obsolete skip in io_xs.t.
  * Label conditionally unused.
  * Use <sys/poll.h> if available before going select().
  * Fix assertion when calling IO::Poll::_poll() with an empty fd array
  * Make IO::Poll->poll call _poll even with an empty fd array

IO 1.35 -- Dec 7 2014 (Not released to CPAN)
  * Improve connected() doc
  * IRIX: fsync documented to fail on read-only filehandles.
  * Convert all use of to Test::More

IO 1.34 -- Sep 10 2014 (Not released to CPAN)
  * Add dual life support for use of op_sibling in IO.xs

IO 1.33 -- Jun 10 2014 (Not released to CPAN)
  * wrap op_sibling field access in OP_SIBLING* macros
  *  Make like() and unlike() in t/ refuse non-qr// arguments
  * Further simplify the sockatmark(). (And do not assign the fd in PREINIT.)

IO 1.32 -- May 29 2014 (Not released to CPAN)
  * fcntl receiving -1 from fileno, fcntl failing.
  * Also very few spots of negative numgroups for getgroups(), and fgetc() return, but almost all checking is for fcntl.
  * merged fix for perl #121743 and perl #121745: hopefully picked up all the fixes-to-fixes from the ticket.
  * Fix for Coverity perl5 CIDs 28990..29003,29005..29011,29013,45354,45363,49926
  * Argument cannot be negative (NEGATIVE_RETURNS) fd is passed to a parameter that cannot be negative.
  * CIDs 29004, 29012: Argument cannot be negative (NEGATIVE_RETURNS) num_groups is passed to a parameter that cannot be negative and because of CIDs 29005 and 29006 also CID 28924.
  * In the first set of issues a fd is retrieved from PerlIO_fileno, and that is then used in places like fstat(), fchown(), dup(), etc., without checking whether the fd is valid (>=0).
  * In the second set of issues a potentially negative number is potentially passed to getgroups().
  * The CIDs 29005 and 29006 were a bit messy: fixing them needed also resolving CID 28924 where the return value of fstat() was ignored, and for completeness adding two croak calls (with perldiag updates): a bit of a waste since it's suidperl code. 

IO 1.31 -- Mar 4 2014 (Not released to CPAN)
  * dist/IO: Allow to be dual-lived - This dual-lived module has not been able to be compiled on releases earlier than 5.10.1.
  * IO::Socket::INET: Handle getprotobyn{ame,umber} not being available
  * dist/IO/t/io_pipe.t: Work around android only having an inbuilt echo
  * Add examples for IO::Socket::UNIX.
  * Remove an old note about autoflush from the POD.
  * ioctl on perlhost platforms take a char*, not void*

IO 1.30 --  Nov 13 2013 (Not released to CPAN)
  * IO.xs: fix compiler warning
  * [perl #75156] fix the return value and bits for removing a closed fh
  * [perl #75156] tests for deleting a closed handle from IO::Select
  * Fix IO::Socket::connect() in the light of $! changes

IO 1.29 -- Mar 15 2013 (Not released to CPAN)
  * Use separate macros for byte vs uv Unicode
  * IO::Socket::INET's documentation for its Listen parameter was somewhat misleading, and the documentation for IO::Socket::Unix even more so.
  * Address [perl #117999] for now by skipping known bad test on AIX
  * [perl #117791] Clarify that write does not match the C 'write' semantics
  *  fix dist/IO/t/cachepropagate-unix.t

IO 1.28 -- Feb 2 2013 (Not released to CPAN)
  * dist/IO/IO.xs: Silence compiler warning. This variable is unused, doesn't need to be declared.

IO 1.27 -- Feb 17 2013 (Not released to CPAN)
  * [perl #116322]: getc() and ungetc() with unicode failure (ungetc() had no knowledge of UTF-8. )

IO 1.26 -- May 13 2009 - Jan 16 2013 (Not released to CPAN)
  * portability to Haiku-OS for the cachepropagate-*.t tests
  * sync() on a read-only file handle doesn't work on cygwin either
  * [ #61577] VMS doesn't support UNIX sockets
  * add Test::More as a prereq to Makefile.PL
  * document the limitations of protocol(), sockdomain(), socktype()
  * [ #61577] try to populate socket info when not cached
  * [ #61577] propagate socket details on accept
  * [ #61577] sockdomain and socktype undef on newly accepted sockets
  * [perl #64772] check both input and output file handles for sync (This allows sync() to be called on directory handles.)
  * [perl #64772] TODO test for sync on read only handle
  * Convert some tests to Test::More
  * Correct bug report email in docs from to
  * Remove ‘use File::Spec’ from IO::File (It is not using it any more.)
  * [RT #36079] Convert ` to '.
  * use :raw to avoid interference from PERL_UNICODE when creating test data
  * Make IO::Handle::getline(s) respect the open pragma (RT 66474)
  * Fix setting sockets nonblocking in Win32
  * Use the exception set in select (connect()) to early return when remote end is busy or in non existing port
  * Keep verbatim pod within 79 cols
  * Keep verbatim pod in within 80 cols
  * [perl #88486] IO::File does not always export SEEK*
  * Explicitly force the load of IO::File in IO::Handle (see the discussion in [perl #87940]).
  * Remove various indirect method calls in IO's docs
  * IO::Select: allow removal of IO::Handle objects without fileno
  * Actuall excise 'Apollo DomainOS' support. We officially killed it in 5.11.0. It hadn't worked for years before that.
  * fix various compiler warnings from XS code (void return value)
  * Only bind to localhost in tests: "in general, tests shouldn't be listening on all interfaces."
  * Document IO::Socket getsockopt and setsockopt
  * Convert sv_2mortal(newSVpvn()) to newSVpvn_flags(), for 5.11.0 and later. (
  * Minor documentation and typo fixes.
  * Move IO from ext to dist in core perl

IO 1.25 -- Wed May 13 18:37:33 CDT 2009
  * Fix test warnings in io_dir
  * skip tests known to cause a segfault 5.10.0

IO 1.24 -- Mon May 11 14:15:51 CDT 2009

  * Make Makefile.PL usable by core and CPAN
  * Reorganize files to be under lib/ directory structure now matches core perl
  * Update with following changes made to core perl distribution
  * Silence Win32 compiler warning in IO.xs
  * Make non-blocking mode work on Windows in IO::Socket::INET
  * fix some missing parts of IO::Handle pod
  * Implement IO::Handle::say the same way as the builtin say().
  * Undo io_linenum.t part of #34148. It was io_multihomed.t that I meant (my mistake), and that is now covered by #34155.
  * watchdog() some IO tests
  * Some more missing isGV_with_GP()s
  * IO::Dir destructor
  * IO::Socket::INET unnecessarily resolves "udp"
  * IO::Handle->say should ignore $\ (bug #49266)
  * consting IO.xs
  * Net::SMTP can't send large messages with bleadperl
  * Fix for IO::Socket send method
  * Fixes for the test suite on OS/2
  * Silence VC++ compiler warnings
  * IO::Socket's IO.xs fails to compile
  * IO::Socket::connect returns wrong errno on timeout
  * Coverity correctly reports that gv might (just) be NULL. So don't dereference it if it is.
  * Simplify tests for fork() capabilities
  * Fix syntax error in io_pipe test
  * Making IO::Socket pass test on Win32
  * ext/IO/t/io_unix.t

IO 1.23 -- Sat Mar 25 19:28:28 CST 2006

 * Adjust the regression tests to use t/ when $ENV{PERL_CORE} is defined
 * Reduce number of calls to getpeername
 * Call qualify on format name passed to format_write. Bug reported by Johan Vromans
 * Reduce calls to getprotobyname/number. Patch from Gisle Aas
 * Remove references to file TEST used in core so appropriate tests are skipped
   during an install from CPAN
 * Add method say to IO::Handle
 * Performance improvement for IO::File::open
 * Don't warn about a directory being closed in the DESTROY

IO 1.22 -- Mon Sep  5 10:29:35 CDT 2005

 * Update with changes made in perl core distribution

Change 173 on 1998/07/14 by <> (Graham Barr)

	- Added method connected
	- Added check that file * is not null
	- Added check for connected
	- Made change to catch recv not returning the address, and added a fix to
	  ensure test does not hang
	- Added check for connected.

Change 137 on 1998/05/21 by <> (Graham Barr)

	- Added checks to all peer* and host* methods for undef

Change 134 on 1998/05/09 by <> (Graham Barr)

	- fix race condition on Solaris & SunOS
	- Applied patch from Gisle Aas <> for
	    documentation update
	- Applied patch from Kuma <>
	    changed input_line_number to be on a per-handle basis.
	- Applied patch from Gisle Aas <> for
	    documentation update
	- Applied patch from Gisle Aas <> for
	    documentation update
	    added sysseek
	IO, IO::Socket::INET
	- documentation update
	- Applied patch from Gisle Aas <> for

Change 133 on 1998/05/09 by <> (Graham Barr)

	- Added checks for blocking()

Sun Apr 12 1998 <> (Graham Barr)

	- enclosed newCONSTSUB in #ifdef as _64 now defines it.

Thu Mar 19 1998 <> (Graham Barr)

	- Changed copyright/distribution policy back to be the same as perl

Sun Feb 15 1998 <> (Graham Barr)

	- Fix to ->accept, accept() returns false on error not undef.

*** Release 1.19

Thu Feb  5 1998 <> (Graham Barr)

	- change copyright notice
	- changed configure to accept PeerHost and LocalHost as well as the
	  PeerAddr and LocalAddr arguments.

Mon Feb  2 1998 <> (Graham Barr)

	- Added printflush so that can be depreciated

	- Remove C<use Config> statement as it was not needed

Tue Jan 27 1998 <> (Graham Barr)

	- removed carp if $^W

*** Patch 1.1804

Sat Jan 17 1998 <> (Graham Barr)

	- Replaced C<Listen => 0> with C<LocalAddr => 'localhost'>
	- Modified the MultiHomed code. Now each address for a given host has
	  a timeout of C<Timeout>.
	- added _get_addr method for doing hostname lookups. Now Net::DNS can be
	  use by sub-classing IO::Socket::INET, Thanks Gisle Aas
	- new test added. Thanks Gisle Aas.

*** Patch 1.1803

Mon Nov 17 1997 <> (Graham Barr)

	- Added #ifdef I_* tests
	- Changed initialization of @domain2pkg to fix problem of Domain option
	  not working
	- Added patch for multi-homed hosts, Thanks to Gisle Aas <>
	- Change default proto to getprotobyname instead of 'tcp' constant string
	- Added patch for multi-homed hosts, Thanks to Gisle Aas <>
	- Change to test fix for Domain problem fixed in IO::Socket and be
	  more comprehensive, Thanks to Gisle Aas <>
	- New test, Thanks to Gisle Aas <>

*** Patch 1.1802

Wed Nov 12 1997 <> (Graham Barr)

	- test 4 made an assumption that was not portable, fixed.

*** Patch 1.1801

Wed Oct 22 1997 <> (Graham Barr)

	- change #ifdef's to allow compilation with 5.002
	- Fix to ensure that socket is not returned as non-blocking
	  unless the user asks for it

	- Fix to stop endless loop

*** Release 1.18

Mon Oct 13 1997 <> (Graham Barr)

	IO.xs, IO::Handle
	- 1.17 broke compatibility with 5.003, small tweaks to restore
	- Added new test to ensure backwards compatibility with constants
	  is not broken

Wed Oct  8 1997 <> (Graham Barr)

	- Added #define's to cope with argument changes to start_subparse
	  from 5.003_22, _23 and _24
	- Renamed has_error to be has_exception which is more correct,
	  has_error is a wrapper around has_exception with a warning if
	  $^W is set.
	- Remove 'linkext' option to WriteMakefile so that static linking
	  should work properly, cannot remember why I added it.

Sun Oct  5 1997 <> (Graham Barr)

	- GLOB assignment does not copy the fileno while under -T
	  added checks for undefined fileno, and added fdopen
	- reader and write can now be called as static methods

	- Attempt to locate <poll.h> and define I_POLL if found

*** Release 1.17

Fri Sep 26 1997 <> (Graham Barr)

	- Fix bug in _poll for ANSI C compilers
	- Split IO::Socket::INET and IO::Socket::UNIX into separate files
	- Patch to open() for when file is in current directory.

*** Release 1.16

Mon 15 Sep 1997 <> Graham Barr

	o New modules
	  - IO::Dir
	  - IO::Poll

	o IO::Socket
	  - Changed new to call autoflush on the new socket
	  - IO::Socket::INET->new now accepts a single argument
	  - IO::Socket::INET default to protocol 'tcp'
	o IO::File
	  - Added doc for new_tmpfile
	o IO::Handle
	  - Removed use of AutoLoader for constants, constants are
	    now defined as constant XS subs
	  - Added fsync, but will not be available for use
	    unless HAS_FSYNC is defined, perls configure does not define
	    this yet.
	  - Moved bootstrap of IO.xs to IO::Handle no longer
	    contains an AUTOLOAD sub in it's ISA hier

	o IO::Seekable
	  - Remove clearerr, as it is defined in IO.xs

	o IO.xs
	  - Patched IO.xs with patch from Chip for setvbuf warning
	  - Added XS sub "constant" for backwards compatibility

	o Misc
	  - Fixed IO::Socket::configure, it was not passing $arg to domain
	    specific package
	  - Changed all $fh variables in IO::Handle to $io and all $fh
	    variables in IO::Socket to $sock as Chip suggested
	  - Fixed usage messages to be consistent

*** Release 1.15

Sun 19 Jan 1997 <> Graham Barr

	o Updated PODs for IO::Handle and IO::File
	o Modified IO.xs so that DESTROY gets called on IO::File
	  objects that were created with IO::File->new_tmpfile
	o Modified the domain2pkg code in IO::Socket so that it
	  does not use blessed refs
	o Created a new package IO::Pipe::End so that pipe specific
	  stuff can be moved out of IO::Handle.
	o Added Ilya's OS/2 changes to and io_pipe.t

	o These changes happened sometime before the release of 1.15
	  - added shutdown to IO::Socket
	  - modified connect to not use alarm
	  - modified accept and connect to use IO::Select

*** Release 1.14

Tue 24 Dec 1996 <> Graham Barr

	o Updated to patches in perl core dist.
	o Added C<use strict> to all modules
	o Modified t/io_sock.t, hopefully the race condition has gone
	o Added close statements to reader/writer in IO::Pipe
	o IO::Handle::syswrite was calling sysread, fixed :-)

*** Release 1.12

Thu 19 Sep 1996 <> Graham Barr

	o Modified IO.xs so that it will compile with pre perlio version
	  of perl (ie pre perl5.003_02)
	o Modified IO::Socket::send so not to pass 4 arguments to send
	  if the socket is connected

*** Release 1.10

Mon 11 Sep 1996 <> Graham Barr

	o Fixed a bug in IO::Socket which caused DESTROY to be called
	  on a partly initialised connection
	o Changed IO.xs to use Perlio
	o Modified usage message to report correct package
	o Added IO::File::new changes from Chip, to allow PERM to be passed
	o Added sysread and syswrite methods to IO::Handle
	o Updated documentation
	o Fixed a bug in IO::Select that caused a hang if the last handle
	  was removed.
	o Added count method to IO::Select
	o Renamed and modified tests so that they can be copied into the
	  perl distribution
	o Added fcntl and ioctl methods to IO::Handle

Thu 25 Jul 1996 <> Graham Barr

	o It is now not necessary to call the domain sub-classes of
	  IO::Socket. when connect is called it notes the domain.
	  Domain specific methods, which are normally non-critical, are
	  called via this note-ing.
	o Added methods to IO::Socket to retrieve the domain, type and
	  protocol of a given socket

Tue 23 Jul 1996 <> Graham Barr

	o IO::Socket::connect changed how we do timeouts, as it did not work

	o IO::Handle::new_from_fd removed method call to _ref_fd, which was
	  a leftover from FileHandle

Fri 28 Jun 1996 <> Graham Barr

	o Modified IO::Socket::UNIX::configure to default to using a socket
	  type of SOCK_STREAM if no type is specified.