ANNOUNCEMENT:
   PICL 2.0, the latest version of the Portable Instrumented Communication
Library, is now available from netlib. PICL 2.0 represents a complete rewrite
of the library, and includes significant new functionality. With the
following exceptions, PICL 2.0 is backward compatible with earlier versions
of the library:

1) PICL 2.0 uses a different trace file format. ParaGraph has been
   updated to use the new format, and the new version of ParaGraph is being
   released simultaneously. 

2) PICL 2.0 embodies a slightly different philosophy than PICL 1.0. PICL is
   (now) a low overhead message-passing compatibility library, supporting
   the writing of portable programs without enforcing it. If a particular
   function is not supported by the native message-passing system, 
   then PICL also does not support it, generating an error message before
   exiting. In the current implementation, this primarily means that
   sendbegin0, sendend0, recvbegin0, and recvend0 are not supported on
   machines that do not provide nonblocking communication commands.
   Portability is still possible, but becomes a matter of programming 
   discipline, avoiding the use of platform-specific commands.

3) PICL 2.0 is not available for the nCUBE/1 and the Cogent. (We no longer 
   have access to these platforms.)

4) For most platforms, the Fortran callable routines have the same names and 
   parameters as the C routines, modulo the usual differences in parameter
   passing. But, on some platforms, C and Fortran external names are
   indistinguishable. To force the correct routines to be linked, PICL 2.0
   also provides versions of the Fortran callable routines with an "f" suffix
   in the name. Thus, for example, to be portable between SUN and RS6000
   workstations, use  
     CALL SEND0F
   instead of 
     CALL SEND0
   when sending a message in a Fortran program.

New documentation is in preparation. In the meantime, a summary of the new
features is provided in the file picl2.commands. The original reference manual
and user guide, a discussion of PICL programming models, and the report
describing the new trace file format are also provided with the distribution.

PLATFORMS:
   In this initial release, PICL 2.0 source is provided for:

1) NX/2 
  - mpsim hypercube simulator, Intel iPSC/2, iPSC/860, DELTA (hostless only),
    Paragon/OSF, and Paragon/SUNMOS

2) VERTEX 3.0 
  - nCUBE/2 and nCUBE/2S

3) PVM 3.3
  - sun and rs6000

A PVM/T3D port will be available in the near future, and other ports are in
progress. 


FUTURE:
   The development of proposed standards like MPI and the popularity of PVM
have decreased the need for low overhead compatibility libraries like PICL,
but standardization in instrumentation interface is less advanced, and may
never occur given the wide range of instrumentation requirements. PICL
instrumentation has proved very useful in our work, and we expect to continue
supporting and extending it by: 

1) implementing PICL on top of MPI, retaining backward compatibility for
   existing PICL programs, and

2) supporting PICL-style instrumentation and the PICL instrumentation
   interface in MPI.

This is a high priority item, and we expect to have something available in
the near future. 


PVM:
   Using the PVM version of PICL on a network of workstations is useful in
developing parallel codes to be run on MPP platforms, but the PICL
message-passing interface and instrumentation logic were designed for
efficiency on tightly coupled homogeneous message-passing systems.
If the primary platform is the network, then the PVM instrumentation and
visualization tools are more appropriate (and powerful).

   Note that commands setdata0 and getdata0 have been added to PICL to
support correct execution on heterogeneous networks. setdata0 is used to
inform PVM what datatype is being sent or received in subsequent send0 and
recv0 calls. The length arguments in send0 and recv0 are still byte counts,
and setdata0 is ignored in PVM on homogeneous networks and in the NX and
VERTEX implementations. getdata0 returns the currently defined datatype.


GETTING SOURCE:
   The PICL source code and documentation are available from the Netlib
software repository. For instructions on how to obtain this material, send
the following message to netlib@ornl.gov:  

send index from picl

You can also use the xnetlib interface to netlib or use Mosaic with the world
wide web address

http://www.netlib.org/picl/index.html


FOR MORE INFORMATION:
   Contact Patrick Worley at worleyph@ornl.gov or (615) 574-3128.