Standard TAP Specification
Revision 1.1

May 15, 1995

Okay, we've gone through a revision and now there's also a sample
server application. Things look good, and PMView works wonderfully
with LiveWire. Thanks to Peter Nielsen for all his help, input,
and expertise.

Les Novell
DataMirage Software

---
January 5, 1995

This is the first attempt at a standard TAP specification on the
OS/2 32-bit platform. This specification is intended to allow separate
processes access to file data while a file is being transferred.
This specification is limited because it does not allow distributed 
processes to share a single file.

Files in this package:
   TAP.DOC        This document
   TAP.H          Shared TAP header file
   TAPAPP.C       TAP Application API code
   TAPAPP.H       TAP Application API header file
   TAPSERVE.C     TAP Server API code
   TAPSERVE.H     TAP Server API header file
   TAPSERVE.RC    TAP Server resources
   TAPRES.H       TAP Server resources header file
   TAPSAMP.C      TAP Application Sample code

To compile the sample TAP Application you'll need to make a project
that includes TAPSAMP.C and TAPAPP.C with dependencies TAP.H and
TAPAPP.H.

For help writing a TAP Server please contact Les Novell on CompUServe 
ID 73631,1233 or from the internet write 73631.1233@compuserve.com.

Brief description of methodology:
=================================
A TAP Server is a single process which mediates access to a file or
files. The TAP Server has both write and read access to shared
file data. The TAP Application(s) is a process that has read access to
file data and whose access is in some ways restricted by the TAP Server.
These processes will be referred to as Server and Application, respectively.

At any time during a file transfer the Server may choose to start one
or more Applications. Each application will be passed a command line
parameter /TAP=<string> where <string> is the name of the pipe.

The Server will pass the following file data down the pipe every time the
length of the file is increased or one of the flags changes:
     FULLY QUALIFIED FILE NAME
     SERVER VERSION STRING
     CURRENT FILE SIZE
     COMPLETE FILE SIZE
     FLAGS
        EMERGENCY CLOSE
        END OF FILE
        BEGINNING OF FILE
        END OF BATCH
        CANCEL

The Application opens and receives the pipe information continuously in
a secondary thread while the Application's primary thread opens the file
for shared reading. The primary thread reads and processes from the file
in a standard way until the transfer is complete. If another file is in
the transfer batch the Application should open it and continue processing 
until the end of batch condition.