perlwin32.pod

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

You may also use dmake.  See L</"Make"> above on how to get it.

Note that MakeMaker actually emits makefiles with different syntax
depending on what 'make' it thinks you are using.  Therefore, it is
important that one of the following values appears in Config.pm:

    make='nmake'	# MakeMaker emits nmake syntax
    make='dmake'	# MakeMaker emits dmake syntax
    any other value	# MakeMaker emits generic make syntax
    			    (e.g GNU make, or Perl make)

If the value doesn't match the 'make' program you want to use,
edit Config.pm to fix it.

If a module implements XSUBs, you will need one of the supported
C compilers.  You must make sure you have set up the environment for
the compiler for command-line compilation.

If a module does not build for some reason, look carefully for
why it failed, and report problems to the module author.  If
it looks like the extension building support is at fault, report
that with full details of how the build failed using the perlbug
utility.

=item Command-line Wildcard Expansion

The default command shells on DOS descendant operating systems (such
as they are) usually do not expand wildcard arguments supplied to
programs.  They consider it the application's job to handle that.
This is commonly achieved by linking the application (in our case,
perl) with startup code that the C runtime libraries usually provide.
However, doing that results in incompatible perl versions (since the
behavior of the argv expansion code differs depending on the
compiler, and it is even buggy on some compilers).  Besides, it may
be a source of frustration if you use such a perl binary with an
alternate shell that *does* expand wildcards.

Instead, the following solution works rather well. The nice things
about it are 1) you can start using it right away; 2) it is more
powerful, because it will do the right thing with a pattern like
*/*/*.c; 3) you can decide whether you do/don't want to use it; and
4) you can extend the method to add any customizations (or even
entirely different kinds of wildcard expansion).

	C:\> copy con c:\perl\lib\Wild.pm
	# Wild.pm - emulate shell @ARGV expansion on shells that don't
	use File::DosGlob;
	@ARGV = map {
		      my @g = File::DosGlob::glob($_) if /[*?]/;
		      @g ? @g : $_;
		    } @ARGV;
	1;
	^Z
	C:\> set PERL5OPT=-MWild
	C:\> perl -le "for (@ARGV) { print }" */*/perl*.c
	p4view/perl/perl.c
	p4view/perl/perlio.c
	p4view/perl/perly.c
	perl5.005/win32/perlglob.c
	perl5.005/win32/perllib.c
	perl5.005/win32/perlglob.c
	perl5.005/win32/perllib.c
	perl5.005/win32/perlglob.c
	perl5.005/win32/perllib.c

Note there are two distinct steps there: 1) You'll have to create
Wild.pm and put it in your perl lib directory. 2) You'll need to
set the PERL5OPT environment variable.  If you want argv expansion
to be the default, just set PERL5OPT in your default startup
environment.

If you are using the Visual C compiler, you can get the C runtime's
command line wildcard expansion built into perl binary.  The resulting
binary will always expand unquoted command lines, which may not be
what you want if you use a shell that does that for you.  The expansion
done is also somewhat less powerful than the approach suggested above.

=item Win32 Specific Extensions

A number of extensions specific to the Win32 platform are available
from CPAN.  You may find that many of these extensions are meant to
be used under the Activeware port of Perl, which used to be the only
native port for the Win32 platform.  Since the Activeware port does not
have adequate support for Perl's extension building tools, these
extensions typically do not support those tools either and, therefore,
cannot be built using the generic steps shown in the previous section.

To ensure smooth transitioning of existing code that uses the
ActiveState port, there is a bundle of Win32 extensions that contains
all of the ActiveState extensions and several other Win32 extensions from
CPAN in source form, along with many added bugfixes, and with MakeMaker
support.  The latest version of this bundle is available at:

    http://search.cpan.org/dist/libwin32/

See the README in that distribution for building and installation
instructions.

=item Notes on 64-bit Windows

Windows .NET Server supports the LLP64 data model on the Intel Itanium
architecture.

The LLP64 data model is different from the LP64 data model that is the
norm on 64-bit Unix platforms.  In the former, C<int> and C<long> are
both 32-bit data types, while pointers are 64 bits wide.  In addition,
there is a separate 64-bit wide integral type, C<__int64>.  In contrast,
the LP64 data model that is pervasive on Unix platforms provides C<int>
as the 32-bit type, while both the C<long> type and pointers are of
64-bit precision.  Note that both models provide for 64-bits of
addressability.

64-bit Windows running on Itanium is capable of running 32-bit x86
binaries transparently.  This means that you could use a 32-bit build
of Perl on a 64-bit system.  Given this, why would one want to build
a 64-bit build of Perl?  Here are some reasons why you would bother:

=over

=item *

A 64-bit native application will run much more efficiently on
Itanium hardware.

=item *

There is no 2GB limit on process size.

=item *

Perl automatically provides large file support when built under
64-bit Windows.

=item *

Embedding Perl inside a 64-bit application.

=back

=back

=head2 Running Perl Scripts

Perl scripts on UNIX use the "#!" (a.k.a "shebang") line to
indicate to the OS that it should execute the file using perl.
Win32 has no comparable means to indicate arbitrary files are
executables.

Instead, all available methods to execute plain text files on
Win32 rely on the file "extension".  There are three methods
to use this to execute perl scripts:

=over 8

=item 1

There is a facility called "file extension associations" that will
work in Windows NT 4.0.  This can be manipulated via the two
commands "assoc" and "ftype" that come standard with Windows NT
4.0.  Type "ftype /?" for a complete example of how to set this
up for perl scripts (Say what?  You thought Windows NT wasn't
perl-ready? :).

=item 2

Since file associations don't work everywhere, and there are
reportedly bugs with file associations where it does work, the
old method of wrapping the perl script to make it look like a
regular batch file to the OS, may be used.  The install process
makes available the "pl2bat.bat" script which can be used to wrap
perl scripts into batch files.  For example:

	pl2bat foo.pl

will create the file "FOO.BAT".  Note "pl2bat" strips any
.pl suffix and adds a .bat suffix to the generated file.

If you use the 4DOS/NT or similar command shell, note that
"pl2bat" uses the "%*" variable in the generated batch file to
refer to all the command line arguments, so you may need to make
sure that construct works in batch files.  As of this writing,
4DOS/NT users will need a "ParameterChar = *" statement in their
4NT.INI file or will need to execute "setdos /p*" in the 4DOS/NT
startup file to enable this to work.

=item 3

Using "pl2bat" has a few problems:  the file name gets changed,
so scripts that rely on C<$0> to find what they must do may not
run properly; running "pl2bat" replicates the contents of the
original script, and so this process can be maintenance intensive
if the originals get updated often.  A different approach that
avoids both problems is possible.

A script called "runperl.bat" is available that can be copied
to any filename (along with the .bat suffix).  For example,
if you call it "foo.bat", it will run the file "foo" when it is
executed.  Since you can run batch files on Win32 platforms simply
by typing the name (without the extension), this effectively
runs the file "foo", when you type either "foo" or "foo.bat".
With this method, "foo.bat" can even be in a different location
than the file "foo", as long as "foo" is available somewhere on
the PATH.  If your scripts are on a filesystem that allows symbolic
links, you can even avoid copying "runperl.bat".

Here's a diversion:  copy "runperl.bat" to "runperl", and type
"runperl".  Explain the observed behavior, or lack thereof. :)
Hint: .gnidnats llits er'uoy fi ,"lrepnur" eteled :tniH

=back

=head2 Miscellaneous Things

A full set of HTML documentation is installed, so you should be
able to use it if you have a web browser installed on your
system.

C<perldoc> is also a useful tool for browsing information contained
in the documentation, especially in conjunction with a pager
like C<less> (recent versions of which have Win32 support).  You may
have to set the PAGER environment variable to use a specific pager.
"perldoc -f foo" will print information about the perl operator
"foo".

One common mistake when using this port with a GUI library like C<Tk>
is assuming that Perl's normal behavior of opening a command-line
window will go away.  This isn't the case.  If you want to start a copy
of C<perl> without opening a command-line window, use the C<wperl>
executable built during the installation process.  Usage is exactly
the same as normal C<perl> on Win32, except that options like C<-h>
don't work (since they need a command-line window to print to).

If you find bugs in perl, you can run C<perlbug> to create a
bug report (you may have to send it manually if C<perlbug> cannot
find a mailer on your system).

=head1 BUGS AND CAVEATS

Norton AntiVirus interferes with the build process, particularly if
set to "AutoProtect, All Files, when Opened". Unlike large applications
the perl build process opens and modifies a lot of files. Having the
the AntiVirus scan each and every one slows build the process significantly.
Worse, with PERLIO=stdio the build process fails with peculiar messages
as the virus checker interacts badly with miniperl.exe writing configure
files (it seems to either catch file part written and treat it as suspicious,
or virus checker may have it "locked" in a way which inhibits miniperl
updating it). The build does complete with

   set PERLIO=perlio

but that may be just luck. Other AntiVirus software may have similar issues.

Some of the built-in functions do not act exactly as documented in
L<perlfunc>, and a few are not implemented at all.  To avoid
surprises, particularly if you have had prior exposure to Perl
in other operating environments or if you intend to write code
that will be portable to other environments, see L<perlport>
for a reasonably definitive list of these differences.

Not all extensions available from CPAN may build or work properly
in the Win32 environment.  See L</"Building Extensions">.

Most C<socket()> related calls are supported, but they may not
behave as on Unix platforms.  See L<perlport> for the full list.
Perl requires Winsock2 to be installed on the system. If you're
running Win95, you can download Winsock upgrade from here:

http://www.microsoft.com/windows95/downloads/contents/WUAdminTools/S_WUNetworkingTools/W95Sockets2/Default.asp

Later OS versions already include Winsock2 support.

Signal handling may not behave as on Unix platforms (where it
doesn't exactly "behave", either :).  For instance, calling C<die()>
or C<exit()> from signal handlers will cause an exception, since most
implementations of C<signal()> on Win32 are severely crippled.
Thus, signals may work only for simple things like setting a flag
variable in the handler.  Using signals under this port should
currently be considered unsupported.

Please send detailed descriptions of any problems and solutions that
you may find to E<lt>F<[e-mail]>E<gt>, along with the output
produced by C<perl -V>.

=head1 ACKNOWLEDGEMENTS

The use of a camel with the topic of Perl is a trademark
of O'Reilly and Associates, Inc. Used with permission.

=head1 AUTHORS

=over 4

=item Gary Ng E<lt>[e-mail]<gt>

=item Gurusamy Sarathy E<lt>[e-mail]<gt>

=item Nick Ing-Simmons E<lt>[e-mail]<gt>

=item Jan Dubois E<lt>[e-mail]<gt>

=item Steve Hay E<lt>[e-mail]<gt>

=back

This document is maintained by Jan Dubois.

=head1 SEE ALSO

L<perl>

=head1 HISTORY

This port was originally contributed by Gary Ng around 5.003_24,
and borrowed from the Hip Communications port that was available
at the time.  Various people have made numerous and sundry hacks
since then.

Borland support was added in 5.004_01 (Gurusamy Sarathy).

GCC/mingw32 support was added in 5.005 (Nick Ing-Simmons).

Support for PERL_OBJECT was added in 5.005 (ActiveState Tool Corp).

Support for fork() emulation was added in 5.6 (ActiveState Tool Corp).

Win9x support was added in 5.6 (Benjamin Stuhl).

Support for 64-bit Windows added in 5.8 (ActiveState Corp).

Last updated: 29 August 2007

=cut