README file for ftp.CS.Arizona.EDU:/sr

This directory contains Version 2.3.1 of the SR programming language and
the archives of the Info-SR mailing list.  Remember to use binary mode
when transferring compressed files.  Tar files should be unpacked in
a new, empty directory.

NOTE to Linux users:  be sure to also get the README.LINUX file.

info-sr.19xx	Archives of the Info-SR mailing list for the given year.
		To subscribe to Info-SR, send your email address to
		info-sr-request@CS.Arizona.EDU.

release.ps	Release notes for SR 2.3, in PostScript.
		(Version 2.3.1 is a minor update with no new release notes.)

sr.tar.Z	The SR programming language, including source code,
		documentation in PostScript and troff form, checkout
		programs, and examples.

vs.tar.Z	The extended verification suite, needed only if you're
		going to modify the system or port it to a new architecture.

For further information about SR, contact sr-project@CS.Arizona.EDU.
Please drop us a note at that address if you pick up SR via FTP.
If you ask us to, we'll put you on the Info-SR mailing list.


Here's a description of SR:

   SR (Synchronizing Resources) is a language for writing concurrent programs.
The main language constructs are resources and operations.  Resources encapsu-
late processes and variables they share; operations provide the primary mechan-
ism for process interaction.  SR provides a novel integration of the mechanisms
for invoking and servicing operations.  Consequently, all of local and remote
procedure call, rendezvous, message passing, dynamic process creation, multi-
cast, and semaphores are supported.  SR also supports shared global variables
and operations.

   SR has been used at a number of universities and labs for course work and
research projects involving concurrent programming.  It has been used in con-
current programming courses to reinforce concepts with small programming pro-
jects and with larger projects such as experiments with parallel algorithms,
replicated databases, distributed simulations, and parts of distributed operat-
ing systems such as file systems and command interpreters.  SR has also been
used as a tool in several masters theses and doctoral dissertations to conduct
experiments in parallel and distributed programming and to implement larger sys-
tems such as a system for mixed language programming, one for distributed imple-
mentation of graph algorithms, experiments with load balancing algorithms, and
experiments with upcall program structures.

Documentation

   SR is described in The SR Programming Language: Concurrency in Practice, by
Gregory R. Andrews and Ronald A. Olsson (Benjamin/Cummings, 1993, ISBN 0-8053-
0088-0).  An overview of version 1 of the language and implementation appeared
in the January, 1988, issue of ACM TOPLAS (10,1, 51-86).  Information about con-
current programming in general can be found in Concurrent Programming: Princi-
ples and Practice, by Gregory R. Andrews (Benjamin/Cummings, 1991, ISBN 0-8053-
0086-4).  These books can be ordered through your local bookstore or by
telephoning 1-800-950-2665 or 1-415-594-4400.

The Implementation

   An SR program runs on one or more networked machines of the same architec-
ture.  True multiprocessing is supported on Silicon Graphics, Intel Paragon,
and Sequent Symmetry systems, and on Sun systems running Solaris 2.3. Multi-
processing is simulated on other platforms, which include SunOS 4.x, HP RISC,
DEC Alpha and Ultrix, IBM AIX, and Linux.  To allow additional hands-on experi-
ence, three preprocessors convert notations for CCRs, monitors, and CSP into
SR code.  The latest implementation of SR is version 2.3, released in October,
1994.

The INFO-SR Mailing List

   Mail sent to info-sr@CS.Arizona.EDU is automatically forwarded to a list of
people interested in SR.  The mailing list is used for language discussions,
announcements of new versions, etc.  To join, send a request including your
e-mail address to info-sr-request@CS.Arizona.EDU.