
	  +============================================================+
	  |                                                            |
	  |                                                            |
	  |               Pipe extension for Win32 Perl                |
	  |               -----------------------------                |
	  |                                                            |
	  |               Version v960610 (Jun 10 1996)                |
	  |               by Dave Roth <rothd@roth.net>                |
	  |                                                            |
	  |                          Credits:                          |
	  |                          --------                          |
	  |               Copyright (c) 1996 Dave Roth.                |
	  |     Copyright (c) 1996 Dave Roth. All rights reserved.     |
	  |    This program is free software; you can redistribute     |
	  |  it and/or modify it under the same terms as Perl itself.  |
	  |                                                            |
	  +============================================================+


 Use under GNU General Public License or Larry Wall's "Artistic License"

This extension gives Win32 Perl the ability to use Named Pipes. Why? Well
considering that Win32 Perl does not (yet) have the ability to fork() I 
could not see what good the pipe(X,Y) was. Besides, where I am an admin
I must have several perl daemons running on several NT Servers. It dawned
on me one day that if I could pipe all these daemons' output to my 
workstation (accross the net) then it would much easier to monitor. This 
was the impetus for an extension using Named Pipes. I think that they are
kinda cool. :)

PIPE.PM HISTORY:
---------------
96.06.10 Dave Roth <rothd@roth.net>
         -Original release. Very buggy and very beta. No guarantees on
		  this stuff, kids!
99.09.25 Gurusamy Sarathy <gsar@activestate.com> (v0.021)
	 - minor fixes for Perl 5.005xx compatibility
	 - delete[] things that got new[]-ed

PIPE.PLL HISTORY:
----------------
96.06.10 Dave Roth <rothd@roth.net>
         -Original release. Just about as bad as the .PM file.
                 

Following in tradition...
*****************************************************************************
*                                                                           *
*  Use under GNU General Public License or Larry Wall's "Artistic License"  *
*                                                                           *
*****************************************************************************

        ----------------------------------------------------------------
NOTICE: I do not guarantee ANYTHING  with this package. If you use it
        you are doing so AT YOUR OWN RISK! I may or may not support this
        depending on my time schedule and I am neither an SQL or ODBC
        guru so do not ask me questions regarding them!
        ----------------------------------------------------------------


I compiled this using MSVC++ 2.2 on an Intel machine. I do not have access to
other platforms to compile on so I will not be doing so. If someone else does,
all the best!


What is the deal with this?
	- You may create as many named pipes as you want (uh, well, as many
	  as your resources will allow).

	- Currently there is a limit of 256 instances of a named pipe (once a
	  pipe is created you can have 256 client/server connections to that
	  name).

	- The default buffer size is 512 bytes, this can be altered by the
	  ResizeBuffer(xxx) method.

	- All named pipes are byte streams. There is currently no way to 
	  alter a pipe to be message based.

    - Other things that I can not think of right now.... :)


What known problems does this thing have?
	- If someone is waiting on a Read() and the other end terminates then
	  you will wait for one REALLY long time! (if anyone has an idea on how 
	  I can detect the termination of the other end let me know!)

	- All pipes are blocking. I am considering using threads and callbacks 
	  into Perl to perform async IO but this may be too much for my time
	  stress. ;)

	- There is no security placed on these pipes.

    - This has not been neither optimized for speed nor optimized for memory
      consumption. This may run into memory bloat.


To test out this ODBC.PLL, install it then run the TEST.PL included with this
archive. You must first, however alter TEST.PL:


** I use a directory structure of \Perl\lib for my library files and this doc is
** assuming you do too. You will, of course, have to compensate for deviations.


    T O   I N S T A L L   T H I S   B E A S T :
    =========================================

1) You will need to dump the PIPE.PM file into the \PERL\LIB\WIN32\ directory.

2) You need to copy either PIPE105.PLL or PIPE106.PLL (depending on your
   version of Win32 Perl's build number. Run:  perl -v   to check which build
   you have) into \PERL\LIB\AUTO\WIN32\PIPE\ directory and rename it to 
   PIPE.PLL.
   
   ---------------------------------------------------------

You are now ready to create named pipes like crazy people!


	T O   T E S T   T H I S   B E A S T :
    ===================================

This package comes equiped with three test files:
  1) SERVER.PL
  2) CLIENT.PL
  3) TEST.BAT
Change to the directory where these three files are and run TEST.BAT.
You can now enter stuff into the Client window and watch the output 
on the Server window. This *should* work accross a network (client on
machine A and server on machine B) but I have not yet tested that.


    T O   U S E   T H I S   B E A S T :
    =================================

Your script will need to have the following line:

    use Win32::Pipe;

Then you need to create a server side of a named pipe:

    $Pipe = new Win32::Pipe("My Pipe Name");

or if you are going to connect to pipe that has already been created:

	$Pipe = new Win32::Pipe("\\\\server\\pipe\\My Pipe Name");

	NOTE: The "\\\\server\\pipe\\" is necessary when connecting to an existing
	      pipe! If you are accessing the same machine you could use
		  "\\\\.\\pipe\\" but either way works fine.

You should check to see if $Pipe is indeed defined otherwise there has been an
error.

Whichever end is the server, it must now wait for a connection...
	
	$Result = $Pipe->Connect();

	NOTE: The client end does not do this! When the client creates the pipe
	      it has already connected!

Now you can read and write data from either end of the pipe:

	$Data = $Pipe->Read();

	$Result = $Pipe->Write("Howdy! This is cool!");

When the server is finished it must disconnect:
	
	$Pipe->Disconnect();

Now the server could Connect() again (and wait for another client) or it could
destroy the named pipe...

    $Data->Close();

The client should Close() in order to properly end the session.


    L I S T   O F   F U N C T I O N S :
    =================================

The PIPE.PM Package supports the following functions:

BufferSize()
	Returns the size of the instance of the named pipe's buffer.
	returns: $BufferSize

Connect()
	Tells the named pipe to create an instance of the named pipe and wait 
	until a client connects.
	returns: TRUE if success
	         FALSE if failure

Disconnect()
	Disconnects (and destroys) the instance of the named pipe from the client.
	returns: TRUE if success
	         FALSE if failure

Error()
	Returns the last error messages pertaining to the named pipe. If used 
	in context to the package.
	returns: ($ErrorNumber, $ErrorText)

new($Name)
	Creates a named pipe if used in server context or a connection to the
	specified named pipe if used in client context.
	Client context is determined by prepending $Name with "\\\\".
	returns: TRUE if success
	         FALSE if failure

Read()
	Reads from the named pipe.
	returns: data read from the pipe if success
	         undef if failure

ResizeBuffer($Size)
	Sets the instance of the named pipe's buffer to $Size.
	returns: $BufferSize if success
	         FALSE if failure

Write($Data)
	Writes $Data to the named pipe.
	returns: TRUE if success
	         FALSE if failure



