Most DPS references are published by Adobe and distributed through their web site. You are most likely to find them through Adobe's search engine.
The PostScript language is documented in the PostScript Language Reference Manual. Unfortunately, the third edition does not document the Display PostScript extensions to PostScript, which are documented in the second edition. Both of these used to be available in PDF from Adobe.
The DPS client library and the DPS/X extensions to DPS are documented in a series of Adobe technical notes: Adobe's DPS technotes. In order, they are:
The DPS/NX agent, a standalone program that allows use of DPS rendering on servers that don't support the DPS extension, is described in
Display PostScript NX Software Concepts and Facilities. Release 1.0. 1 June 1993. DPSNX.Doc.pdf.
The best reference to NeXT's extensions to DPS is, curiously enough, Sun's documentation. See the Solaris X Window System Developer's Guide (in the Solaris Software Developer Collection), Chapter 2, DPS Features and Enhancements, available from Sun's web site.
The best known book for learning DPS is Programming the Display Postscript System With X, Adobe Systems Incorporated. Addison-Wesley 1993, ISBN 0-201-62203-3. The better-known version of this book is Programming the Display Postscript System With NeXTStep, Adobe Systems Incorporated, which is currently out of print.
Developing Applications for the Display PostScript System is a DPS/X programming manual by the people who once were called Digital.
Juliusz Chroboczek, <email@example.com>
Copyright © 2000-2001 by Juliusz Chroboczek
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