Using Threads in Interactive Systems: A Case Study
Technical Report CSL 93-16
Computer Science Laboratory
Xerox Palo Alto Research Center
3333 Coyote Hill Road
Palo Alto, CA 94304
Copyright (c) Xerox Corporation 1993. All rights reserved.

Postscript and Interpress masters for CSL 93-16 may be found
in the directory ThreadStudyPaper/ along with the
source file.

This CDROM contains (most of) the current source for the Cedar
programming environment as developed over the last ten
years by the the Computer Science Laboratory at Xerox's Palo Alto
Research Center.

Our principle purpose in releasing this CDROM is to allow other
researchers to peruse the Cedar source code. The most convenient way
to do this, if you happen to own a SPARC-based workstation running the SunOS4.1.x
or Solaris2 operating system and the X11 Window System
will be to actually start up a Cedar system and use
the Cedar Tioga editor for browsing the files.

Starting Cedar:

For SPARC-based SunOS4.1.x and Solaris2 machines, we've set things up so
that you can run the Cedar system directly from the CDROM. Mount it
with type hsfs and on SunOS4.1.x do
 % setenv XeroxCedar <mount point>/Cedar
 % cd $XeroxCedar/cdpackage/solaris1
 % x11v
 
For SPARC-based Solaris2 machines use
 % setenv XeroxCedar <mount point>/Cedar
 % cd $XeroxCedar/cdpackage/solaris2
 % x11v
 
At this point you would do well to print the file
 $XeroxCedar/doc/CedarPrimer.ps
for a general introduction to Cedar and some hints on using it from the
mouse and keyboard. (If you happen to have an Interpress printer
you could instead print CedarPrimer.interpress
from the same directory.)

If you do not have an appropriate workstation to run Cedar you may not be
completely out of luck. We have also included the viewtioga package
for the Andrew ez editor and some emacs elisp packages that provide
the ability to read files in tioga's format. The viewtioga package will require
expertise in ez to install. Look in the viewtioga subdirectory of the
top level directory. Necessary fonts for viewtioga can be found
in the Xfonts directory. The elisp packages are in the emacs subdirectory and
should be easy to install. Emacs conversion is pretty slow,
but it does let you look at tioga files.

The cedarname utility also uses the XeroxCedar environment variable as
does the viewtioga package. Unfortunately some uses of the variable
refer to ${XeroxCedar}/.. which may cause trouble if you copy the
CDROM to magnetic disk and split the contents across multiple file
systems. The system has facilities to cope with the situation but
they require more work than simply setting a single environment
variable.

Also included on this CDROM are the interfaces of our POSIX
Portable Common Runtime (PPCR). When you run Cedar off of this CDROM,
PPCR provides the threads and garbage collection as well as the POSIX
environment, but PPCR should itself not be too apparent.

The usual way of running Cedar at PARC is using more mature version of
the runtime called PCR. Since PCR requires customization of the Unix
kernel and does not run on Solaris2 we decided to supply the PPCR-based
Cedar for the CDROM, even though it is not as complete a development
environment as the PCR-based version. It has also not seen the
performance tuning that Cedar on PCR has.

The latest released version of PCR is available from parcftp.xerox.com in directory
/pub/pcr. Several papers about PCR are available from the same directory.

Legalities:
Please refer to the file COPYRIGHT in the top level directory.

Contact:
Recipients of this disk or the files on it are asked to please notify

  PCR Coordinator
  Xerox Palo Alto Research Center
  3333 Coyote Hill Road
  Palo Alto CA 94304
  pcrcoordinator@parc.xerox.com

of their postal or electronic mail address.