=head1 NAME

Win32 - Interfaces to some Win32 API Functions

=head1 DESCRIPTION

Perl on Win32 contains several functions to access Win32 APIs. Some
are included in Perl itself (on Win32) and some are only available
after explicitly requesting the Win32 module with:

	use Win32;

The builtin functions are marked as [CORE] and the other ones
as [EXT] in the following alphabetical listing. The C<Win32> module
is not part of the Perl source distribution; it is distributed in
the libwin32 bundle of Win32::* modules on CPAN. The module is
already preinstalled in binary distributions like ActivePerl.

=head2 Alphabetical Listing of Win32 Functions

=over

=item Win32::AbortSystemShutdown(MACHINE)

[EXT] Aborts a system shutdown (started by the
InitiateSystemShutdown function) on the specified MACHINE.

=item Win32::BuildNumber()

[CORE] Returns the ActivePerl build number. This function is
only available in the ActivePerl binary distribution.

=item Win32::CopyFile(FROM, TO, OVERWRITE)

[CORE] The Win32::CopyFile() function copies an existing file to a new
file. All file information like creation time and file attributes will
be copied to the new file. However it will B<not> copy the security
information. If the destination file already exists it will only be
overwritten when the OVERWRITE parameter is true. But even this will
not overwrite a read-only file; you have to unlink() it first
yourself.

=item Win32::DomainName()

[CORE] Returns the name of the Microsoft Network domain that the
owner of the current perl process is logged into.

=item Win32::ExpandEnvironmentStrings(STRING)

[EXT] Takes STRING and replaces all referenced environment variable
names with their defined values. References to environment variables
take the form C<%VariableName%>. Case is ignored when looking up the
VariableName in the environment. If the variable is not found then the
original C<%VariableName%> text is retained.  Has the same effect
as the following:

	$string =~ s/%([^%]*)%/$ENV{$1} || "%$1%"/eg

=item Win32::FormatMessage(ERRORCODE)

[CORE] Converts the supplied Win32 error number (e.g. returned by
Win32::GetLastError()) to a descriptive string.  Analogous to the
perror() standard-C library function.  Note that C<$^E> used
in a string context has much the same effect.

	C:\> perl -e "$^E = 26; print $^E;"
	The specified disk or diskette cannot be accessed

=item Win32::FsType()

[CORE] Returns the name of the filesystem of the currently active
drive (like 'FAT' or 'NTFS'). In list context it returns three values:
(FSTYPE, FLAGS, MAXCOMPLEN). FSTYPE is the filesystem type as
before. FLAGS is a combination of values of the following table:

	0x00000001  supports case-sensitive filenames
	0x00000002  preserves the case of filenames
	0x00000004  supports Unicode in filenames
	0x00000008  preserves and enforces ACLs
	0x00000010  supports file-based compression
	0x00000020  supports disk quotas
	0x00000040  supports sparse files
	0x00000080  supports reparse points
	0x00000100  supports remote storage
	0x00008000  is a compressed volume (e.g. DoubleSpace)
	0x00010000  supports object identifiers
	0x00020000  supports the Encrypted File System (EFS)

MAXCOMPLEN is the maximum length of a filename component (the part
between two backslashes) on this file system.

=item Win32::FreeLibrary(HANDLE)

[EXT] Unloads a previously loaded dynamic-link library. The HANDLE is
no longer valid after this call. See L<LoadLibrary> for information on
dynamically loading a library.

=item Win32::GetArchName()

[EXT] Use of this function is deprecated. It is equivalent with
$ENV{PROCESSOR_ARCHITECTURE}. This might not work on Win9X.

=item Win32::GetChipName()

[EXT] Returns the processor type: 386, 486 or 586 for Intel processors,
21064 for the Alpha chip.

=item Win32::GetCwd()

[CORE] Returns the current active drive and directory. This function
does not return a UNC path, since the functionality required for such
a feature is not available under Windows 95.

=item Win32::GetFullPathName(FILENAME)

[CORE] GetFullPathName combines the FILENAME with the current drive
and directory name and returns a fully qualified (aka, absolute)
path name. In list context it returns two elements: (PATH, FILE) where
PATH is the complete pathname component (including trailing backslash)
and FILE is just the filename part.  Note that no attempt is made to
convert 8.3 components in the supplied FILENAME to longnames or
vice-versa.  Compare with Win32::GetShortPathName and
Win32::GetLongPathName.  

This function has been added for Perl 5.6.

=item Win32::GetLastError()

[CORE] Returns the last error value generated by a call to a Win32 API
function.  Note that C<$^E> used in a numeric context amounts to the
same value.

=item Win32::GetLongPathName(PATHNAME)

[CORE] Returns a representaion of PATHNAME comprised of longname
compnents (if any).  The result may not necessarily be longer
than PATHNAME.  No attempt is made to convert PATHNAME to the
absolute path.  Compare with Win32::GetShortPathName and
Win32::GetFullPathName.

This function has been added for Perl 5.6.

=item Win32::GetNextAvailDrive()

[CORE] Returns a string in the form of "<d>:" where <d> is the first
available drive letter.

=item Win32::GetOSVersion()

[CORE] Returns the array (STRING, MAJOR, MINOR, BUILD, ID), where
the elements are, respectively: An arbitrary descriptive string, the
major version number of the operating system, the minor version
number, the build number, and a digit indicating the actual operating
system. For ID, the values are 0 for Win32s, 1 for Windows 9X and 2
for Windows NT. In scalar context it returns just the ID.

=item Win32::GetShortPathName(PATHNAME)

[CORE] Returns a representation of PATHNAME comprised only of
short (8.3) path components.  The result may not necessarily be
shorter than PATHNAME.  Compare with Win32::GetFullPathName and
Win32::GetLongPathName.

=item Win32::GetProcAddress(INSTANCE, PROCNAME)

[EXT] Returns the address of a function inside a loaded library. The
information about what you can do with this address has been lost in
the mist of time. Use the Win32::API module instead of this deprecated
function.

=item Win32::GetTickCount()

[CORE] Returns the number of milliseconds elapsed since the last
system boot. Resolution is limited to system timer ticks (about 10ms
on WinNT and 55ms on Win9X).

=item Win32::InitiateSystemShutdown(MACHINE, MESSAGE, TIMEOUT, FORCECLOSE, REBOOT)

[EXT] Shutsdown the specified MACHINE, notifying users with the
supplied MESSAGE, within the specified TIMEOUT interval. Forces
closing of all documents without prompting the user if FORCECLOSE is
true, and reboots the machine if REBOOT is true. This function works
only on WinNT.

=item Win32::IsWinNT()

[CORE] Returns non zero if the Win32 subsystem is Windows NT.

=item Win32::IsWin95()

[CORE] Returns non zero if the Win32 subsystem is Windows 95.

=item Win32::LoadLibrary(LIBNAME)

[EXT] Loads a dynamic link library into memory and returns its module
handle. This handle can be used with Win32::GetProcAddress and
Win32::FreeLibrary. This function is deprecated. Use the Win32::API
module instead.

=item Win32::LoginName()

[CORE] Returns the username of the owner of the current perl process.

=item Win32::LookupAccountName(SYSTEM, ACCOUNT, DOMAIN, SID, SIDTYPE)

[EXT] Looks up ACCOUNT on SYSTEM and returns the domain name the SID and
the SID type.

=item Win32::LookupAccountSID(SYSTEM, SID, ACCOUNT, DOMAIN, SIDTYPE)

[EXT] Looks up SID on SYSTEM and returns the account name, domain name,
and the SID type.

=item Win32::MsgBox(MESSAGE [, FLAGS [, TITLE]])

[EXT] Create a dialogbox containing MESSAGE. FLAGS specifies the
required icon and buttons according to the following table:

	0 = OK
	1 = OK and Cancel
	2 = Abort, Retry, and Ignore
	3 = Yes, No and Cancel
	4 = Yes and No
	5 = Retry and Cancel

	MB_ICONSTOP          "X" in a red circle
	MB_ICONQUESTION      question mark in a bubble
	MB_ICONEXCLAMATION   exclamation mark in a yellow triangle
	MB_ICONINFORMATION   "i" in a bubble

TITLE specifies an optional window title. The default is "Perl".

The function returns the menu id of the selected push button:

	0  Error

	1  OK
	2  Cancel
	3  Abort
	4  Retry
	5  Ignore
	6  Yes
	7  No

=item Win32::NodeName()

[CORE] Returns the Microsoft Network node-name of the current machine.

=item Win32::RegisterServer(LIBRARYNAME)

[EXT] Loads the DLL LIBRARYNAME and calls the function DllRegisterServer.

=item Win32::SetCwd(NEWDIRECTORY)

[CORE] Sets the current active drive and directory. This function does not
work with UNC paths, since the functionality required to required for
such a feature is not available under Windows 95.

=item Win32::SetLastError(ERROR)

[CORE] Sets the value of the last error encountered to ERROR. This is
that value that will be returned by the Win32::GetLastError()
function. This functions has been added for Perl 5.6.

=item Win32::Sleep(TIME)

[CORE] Pauses for TIME milliseconds. The timeslices are made available
to other processes and threads.

=item Win32::Spawn(COMMAND, ARGS, PID)

[CORE] Spawns a new process using the supplied COMMAND, passing in
arguments in the string ARGS. The pid of the new process is stored in
PID. This function is deprecated. Please use the Win32::Process module
instead.

=item Win32::UnregisterServer(LIBRARYNAME)

[EXT] Loads the DLL LIBRARYNAME and calls the function
DllUnregisterServer.

=back

=cut
