PLOT_PS: A PostScript C graphic library for U*ix, VMS and MS/DOS. Jean-Francois VIBERT CHU Saint-Antoine Paris France PLOT_PS is a library of graphic C functions designed to build PostScript files from C programs. This library allows the production of graphics on a PostScript printer such as the DEC LN03R or any standard PostScript printer. All functions begin with the prefix ps_ and need to have the plot_ps.h header file included. The very first function to be called is ps_iniplot. It opens the postscript file. PLOT_PS allows to work in both absolute (in cms) and user or subject space. Inclusion of PS file or of plain PostScript code is also possible with PLOT_PS. The file inclusion possibility allows the inclusion of a drawing obtained with any wysiwyg interactive drawing program. The very last function call must be ps_endplot which closes the postscript file and spool it or not. The set of primitives provided is very similar to what was provided in the Benson plotter library: open file, vector and polygon (empty of filled) drawing, text drawing with multiple fonts and sizes, text and graphics rotation and zooming, axis drawing, 3D vectors and surfaces drawing etc. Full C source code, documentation in TeX and PostScript format is provided. PLOT_PS can be built under U*ix, VMS and MS-DOS (using MSC).