Solaris X Window System Developer's Guide

Chapter 1 Introduction to the Solaris X Server

This chapter provides information on the Solaris X server. The Solaris X server implements the X Window System client-server model for the Solaris product. The chapter includes information on the following topics:

About the Solaris X Server

The Solaris X server, XSun, is composed of the X Consortium's X11R6 sample server with the Display PostScript (DPS) imaging system extension, additional X Consortium X extensions, and Sun added value. The Solaris X server is the foundation for the Common Desktop Environment (CDE) and underlies the CDE desktop. The server handles communication between client applications, the display hardware, and input devices. By default, the Solaris X server runs with the CDE dtlogin and window manager (dtwm), but any X Window System manager that is ICCCM (Inter-Client Communication Conventions Manual) compliant runs with the server. Software developers can write applications for the Solaris environment using the Xlib library or a variety of toolkits, including the Motif toolkit and the Xt toolkit.

Figure 1–1 illustrates the relationship between the Solaris X server, several desktop client applications, the display, and input devices.

Figure 1–1 Solaris X Server


X11R6 Sample Server

An important component of the Solaris X server is the X11R6 sample server from the X Consortium. The X11R6 sample server was designed and implemented to be portable; it hides differences in the underlying hardware from client applications. The sample server handles all drawing, interfaces with device drivers to receive input, and manages off-screen memory, fonts, cursors, and colormaps.

The sample server contains the following parts, or layers:

Figure 1–2 illustrates the structure of the server. Note that throughout this document, server is used interchangeably with the Solaris X server, and sample server is used interchangeably with the X Consortium's X11R6 sample server.

Figure 1–2 Solaris X Server Architecture


DPS Extension

In addition to the X11R6 sample server, the Solaris X server includes the Display PostScript system. DPS provides X applications with the PostScript imaging model and with access to the Adobe Type Library. The Display PostScript system is implemented as an extension to the X Window System as part of the client-server network architecture; the extension is sometimes referred to as DPS/X [This section is based on Chapter 2 of Programming the Display PostScript System with X by Adobe Systems Incorporated (Addison-Wesley Publishing Company, Inc., 1993) and is used with the permission of the copyright holder.] .

In the DPS system, the PostScript interpreter is implemented as an extension to the X server, and each application is a client. The application sends PostScript language code to the server through single operator calls, and data can be returned from the server in the form of output arguments. DPS client-server communication is implemented transparently using the low-level communication protocols provided by the X Window System. For more information on the DPS system, see Chapter 2, DPS Features and Enhancements.

X Consortium Extensions

The Solaris X server supports X extensions as defined by the X Consortium. These extensions are briefly described in the sections below. The sections provide the specification name for each extension, as well as the associated file name (on in parentheses. For information on the standard X Extension Mechanism, see The X Window System Server and the Xlib Programming Manual.

The X Consortium X11 standards referenced in the following sections are readily available to systems on the World Wide Web. The URL is The X11 documentation resides in the /pub/R6untarred/mit/doc/extensions directory on the machine. Use the file transfer protocol (ftp) to download files from this system. If you need help using ftp, refer to the ftp(1) man page. To determine if your system is connected to the World Wide Web, see your system administrator.

X Input Extension

The X Input Extension is Sun's implementation of the X Consortium standard, X11 Input Extension Protocol Specification (/pub/X11/R6.1/xc/doc/specs/Xi/ This extension controls access to alternate input devices (that is, other than the keyboard and pointer). It allows client programs to select input from these devices independently of each other and independently of the core devices.

Double Buffer Extension

The double buffer extension (DBE) is Sun's implementation of the X Consortium standard. Double-buffering provides flicker-free animation capabilities by allowing applications to show the user only completely rendered frames. Frames are rendered in a non-displayed buffer and then moved into a displayed buffer.

Shape Extension

The Shape Extension is Sun's full implementation of the X Consortium standard, X11 Nonrectangular Window Shape Extension ( This extension provides the capability of creating arbitrary window and border shapes within the X11 protocol.

Shared Memory Extension

The Shared Memory extension is Sun's full implementation of the X Consortium experimental Shared Memory Extension ( This extension provides the capability to share memory XImages and pixmaps by storing the actual image data in shared memory. This eliminates the need to move data through the Xlib interprocess communication channel; thus, for large images, system performance increases. This extension is useful only if the client application runs on the same machine as the server.

XTEST Extension

The XTEST extension is Sun's full implementation of the X Consortium proposed standard, X11 Input Synthesis Extension Proposal ( This extension provides the capability for a client to generate user input and to control user input actions without a user being present. This extension requires modification to the DDX layer of the server.

Miscellaneous Extension

The MIT-SUNDRY-NONSTANDARD extension was developed at MIT and does not have a standard, or specification, on the machine. This extension handles miscellaneous erroneous protocol requests from X11R3 and earlier clients. It provides a request that turns on bug-compatibility mode so that certain erroneous requests are handled or turns off bug-compatibility mode so that an error for erroneous requests is returned. The extension also provides a request that gets the current state of the mode.

This extension can be dynamically turned on or off with xset, or at server startup with openwin. See the xset(1) and openwin(1) man pages, specifically the -bc option, for more information.


This standard X Consortium extension allows an application to recycle XIDs. Some applications create and destroy XIDs so rapidly that they exceed the fixed range of XIDs. Most applications do not need to use this extension. The specification is in /pub/X11/xc/doc/specs/Xext/

X Imaging Extension

The X Imaging Extension (XIE) is Sun's implementation of the X Consortium standard.


The Solaris X server also supports keyboard features compliant with the American Disabilities Act (ADA). These features are available through an extension to the server, called AccessX. The AccessX extension provides the following capabilities: sticky keys, slow keys, toggle keys, mouse keys, bounce keys and repeat keys. Use the client program accessx to enable and disable these capabilities. The accessx client controls the toggle, bounce, and repeat keys and their settings. The sticky, slow, and mouse keys can be enabled using shift or other keys. For information on using AccessX, see the Solaris User's Guide.

Before running accessx, set the UIDPATH environment variable to /usr/openwin/lib/app-defaults/accessx.uid.

The accessx client is part of the SUNWxwacx package. To install it, you need to install the All Cluster.

Shared Memory Transport

The Solaris X server includes the Sun extension SUN_SME, Sun's implementation of a shared memory transport mechanism. This extension provides the capability of sending client requests to the server via shared memory. Shared memory is used for client requests only. Replies from the server and events are sent via the default transport mechanism. To enable this transport mechanism, set the DISPLAY environment variable to :x.y, where x is the display number, and y is the screen number, and set the environment variable XSUNTRANSPORT to shmem. The size of the segment can be set by setting the environment variable XSUNSMESIZE to the desired size in Kbytes. By default, XSUNSMESIZE is set to 64.

Visual Overlay Windows

The Solaris X server supports two application programmer's interfaces (APIs) that enable use of overlay windows. An overlay is a pixel buffer (either physical or software-simulated) into which graphics can be drawn. Applications can use overlays to display temporary imagery in a display window. For more information on the overlay APIs, see Chapter 5, Server Overlay Windowsand Chapter 6, Transparent Overlay Windows.

X11 Libraries

Table 1–1 lists the X11 libraries. The .so and .a files that comprise these

libraries are in /usr/openwin/lib.

Table 1–1 X11 Libraries
 Library Description Available From the X Consortium Sun Value Added




MT safe 

Dynamic loading of locale 

Search path includes /usr/openwin,

New keysyms 


X Authorization library 




Athena Widget Set library 




X Extensions library 


Bug fixes, transparent overlays 


Binary compatibility library for previous input extension 


Sun library 


Xinput Extension library 


Bug fixes 

Supports Solaris X extensions 


X Miscellaneous Utilities library 


Search path includes/usr/openwin


OLIT library 


Sun product—see the preface for a list of OLIT manuals (Available from USL) 


Xt Intrinsics library 




XView library 


Sun product donated to X Consortium 

Bug fixes not included in X11R6 libxview

64-bit X11 Libraries

For 64-bit Solaris installations, 64-bit versions of the following X11 shared libraries are located in /usr/openwin/lib/sparcv9.

In addition, 64-bit versions of the following lint libraries for programmers are

located in /usr/openwin/lib/sparcv9






Applications That Run With the Solaris X Server

You can run the following kinds of applications with the Solaris X server:

Supported X11 Applications

The Solaris X server supports the following client applications available from the X Consortium. These clients are also included as part of the Solaris environment.

Unsupported Applications

The following are some applications and libraries, all of which are available from the X Consortium, that run on the server but are not distributed or supported by Sun:

OpenWindows Directory Structure

The OpenWindows directory structure, which includes the Solaris X server executable and X11 core distribution libraries, is shown in Figure 1–3. Note that /openwin/etc is a symbolic link to /openwin/share/etc, /openwin/include is a link to /openwin/share/include, and /openwin/man is a link to /openwin/share/man. The /share directory contains architecture-independent files.

For more information on the X11 libraries in /openwin/lib, see X11 Libraries.

Figure 1–3 OpenWindows Directory Structure


Table 1–2 briefly describes the contents of the top level directories in the OpenWindows directory structure.

Table 1–2 OpenWindows Directories
 Directory Subdirectory Content



US and international keytables, and



ToolTalk® data files



/patterns (.xbm files and attributes)



X11 header files, /DPS, /Xaw, /Xmu, /bitmaps, /extensions



Symbolic link to /include/X11



OLIT header files 



generic.h header file 



Classing engine header files 



dga.h header file 



libhelp header files



Various bitmap files  



olgx header file



Pixrect header files 



c_varieties.h and portable.h header files



XView header files 



Server support files, /fonts, and DPS .upr files



OLIT data files 



X applications default files 



Classing Engine tables 



imake files



Symbolic link to /locale/C/help



Profiles libraries 



Locale libraries (/C, /iso_8859_1)



Xdm configuration files



64-bit X libraries 


/man1, /man1m

OpenWindows command man pages 



Library man pages, for XView, OLIT, Xt, Xlib, etc. 



AnswerBook man pages 



File format man pages 



Demos man pages 



Non-command man pages 


Server private files for internal use only 



Location of files in /etc



/PostScript, /fish, /raster



Location of files in /include



Location of files in /lib/locale



Location of files in /man



/dig_samples, /extensions, /fonts, /olit, /tooltalk, /xview




Notes on X11 Programming

Common X11 programming issues are discussed in the following sections.

Compose Key Support

The OpenWindows version of Xlib supports Compose Key processing through calls to XLookupString.

x86 only –

On IA keyboards, use the Control-Shift-F1 key sequence for the Compose Key functionality.

NumLock Key Support

The OpenWindows version of Xlib supports NumLock Key processing through calls to XLookupString. This change does not affect the NumLock processing that exists in XView, OLIT, Motif, or X applications.

x86 only –

On IA keyboards, the NumLock Key resides in the top line of the keypad section of the keyboard.

Color Name Database

The color name database provides a mapping between ASCII color names and RGB color values. This mapping increases the portability of color programs and eases programming. Note that this mapping is subjective and has no objective scientific basis.

The source of the database is /usr/openwin/lib/X11/rgb.txt. This file is identical to the one provided in X11R6 from the X Consortium. rgb.txt is compiled into the dbm(3) database files, rgb.dir and rgb.pag. When the server starts up, it builds an internal representation of rgb.dir and rgb.pag used to map a color name to a color value.

X11 clients use XLookupColor or XAllocNamedColor to map a color name to a color value. The color name string passed to these routines is converted to lowercase before it is looked up in the database.

Color Recommendations

This section contains recommendations for using the Solaris X server color support facilities. Use these hints to maximize portability and color sharing:

Further Reading

There are numerous books on all aspects of X and the X Window System. For more information on the X Window System, see Related Booksof the preface for a list of recommended books available through SunExpress and your local book store. For more information on the Solaris X server and the X Consortium sample server, see the following manual pages: