.\" $XConsortium: Xserver.man,v 1.55 94/05/16 12:19:55 dpw Exp $ .\" Copyright (c) 1984 - 1991, 1993, 1994 X Consortium .\" .\" Permission is hereby granted, free of charge, to any person obtaining .\" a copy of this software and associated documentation files (the .\" "Software"), to deal in the Software without restriction, including .\" without limitation the rights to use, copy, modify, merge, publish, .\" distribute, sublicense, and/or sell copies of the Software, and to .\" permit persons to whom the Software is furnished to do so, subject to .\" the following conditions: .\" .\" The above copyright notice and this permission notice shall be included .\" in all copies or substantial portions of the Software. .\" .\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS .\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. .\" IN NO EVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR .\" OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, .\" ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR .\" OTHER DEALINGS IN THE SOFTWARE. .\" .\" Except as contained in this notice, the name of the X Consortium shall .\" not be used in advertising or otherwise to promote the sale, use or .\" other dealings in this Software without prior written authorization .\" from the X Consortium. .TH XSERVER 1 "Release 6" "X Version 11" .SH NAME Xserver \- X Window System display server .SH SYNOPSIS .B X [option ...] .SH DESCRIPTION .I X is the generic name for the X Window System display server. It is frequently a link or a copy of the appropriate server binary for driving the most frequently used server on a given machine. .SH "STARTING THE SERVER" The X server is usually started from the X Display Manager program \fIxdm(1)\fP. This utility is run from the system boot files and takes care of keeping the server running, prompting for usernames and passwords, and starting up the user sessions. .PP Installations that run more than one window system may need to use the \fIxinit(1)\fP utility instead of \fIxdm\fP. However, \fIxinit\fP is to be considered a tool for building startup scripts and is not intended for use by end users. Site administrators are \fBstrongly\fP urged to use \fIxdm\fP, or build other interfaces for novice users. .PP The X server may also be started directly by the user, though this method is usually reserved for testing and is not recommended for normal operation. On some platforms, the user must have special permission to start the X server, often because access to certain devices (e.g. /dev/mouse) is restricted. .PP When the X server starts up, it typically takes over the display. If you are running on a workstation whose console is the display, you may not be able to log into the console while the server is running. .SH OPTIONS All of the X servers accept the following command line options: .TP 8 .B :\fIdisplaynumber\fP the X server runs as the given \fIdisplaynumber\fP, which by default is 0. If multiple X servers are to run simultaneously on a host, each must have a unique display number. See the DISPLAY NAMES section of the \fIX(1)\fP manual page to learn how to specify which display number clients should try to use. .TP 8 .B \-a \fInumber\fP sets pointer acceleration (i.e. the ratio of how much is reported to how much the user actually moved the pointer). .TP 8 .B \-ac disables host-based access control mechanisms. Enables access by any host, and permits any host to modify the access control list. Use with extreme caution. This option exists primarily for running test suites remotely. .TP 8 .B \-audit \fIlevel\fP Sets the audit trail level. The default level is 1, meaning only connection rejections are reported. Level 2 additionally reports all successful connections and disconnects. Level 0 turns off the audit trail. Audit lines are sent as standard error output. .TP 8 .B \-auth \fIauthorization-file\fP Specifies a file which contains a collection of authorization records used to authenticate access. See also the \fIxdm\fP and \fIXsecurity\fP manual pages. .TP 8 .B bc disables certain kinds of error checking, for bug compatibility with previous releases (e.g., to work around bugs in R2 and R3 xterms and toolkits). Deprecated. .TP 8 .B \-bs disables backing store support on all screens. .TP 8 .B \-c turns off key-click. .TP 8 .B c \fIvolume\fP sets key-click volume (allowable range: 0-100). .TP 8 .B \-cc \fIclass\fP sets the visual class for the root window of color screens. The class numbers are as specified in the X protocol. Not obeyed by all servers. .TP 8 .B \-co \fIfilename\fP sets name of RGB color database. The default is /lib/X11/rgb, where refers to the root of the X11 install tree. .TP 8 .B \-config \fIfilename\fP reads more options from the given file. Options in the file may be separated by newlines if desired. If a '#' character appears on a line, all characters between it and the next newline are ignored, providing a simple commenting facility. The \fB\-config\fP option itself may appear in the file. .TP 8 .B \-core causes the server to generate a core dump on fatal errors. .TP 8 .B \-dpi \fIresolution\fP sets the resolution of the screen, in dots per inch. To be used when the server cannot determine the screen size from the hardware. .TP 8 .B \-deferglyphs \fIwhichfonts\fP specifies the types of fonts for which the server should attempt to use deferred glyph loading. \fIwhichfonts\fP can be all (all fonts), none (no fonts), or 16 (16 bit fonts only). .TP 8 .B \-f \fIvolume\fP sets feep (bell) volume (allowable range: 0-100). .TP 8 .B \-fc \fIcursorFont\fP sets default cursor font. .TP 8 .B \-fn \fIfont\fP sets the default font. .TP 8 .B \-fp \fIfontPath\fP sets the search path for fonts. This path is a comma separated list of directories which the X server searches for font databases. .TP 8 .B \-help prints a usage message. .TP 8 .B \-I causes all remaining command line arguments to be ignored. .TP 8 .B \-kb disables the XKEYBOARD extension if present. .TP 8 .B \-p \fIminutes\fP sets screen-saver pattern cycle time in minutes. .TP 8 .B \-pn permits the server to continue running if it fails to establish all of its well-known sockets (connection points for clients), but establishes at least one. .TP 8 .B \-r turns off auto-repeat. .TP 8 .B r turns on auto-repeat. .TP 8 .B \-s \fIminutes\fP sets screen-saver timeout time in minutes. .TP 8 .B \-su disables save under support on all screens. .TP 8 .B \-t \fInumber\fP sets pointer acceleration threshold in pixels (i.e. after how many pixels pointer acceleration should take effect). .TP 8 .B \-terminate causes the server to terminate at server reset, instead of continuing to run. .TP 8 .B \-to \fIseconds\fP sets default connection timeout in seconds. .TP 8 .B \-tst disables all testing extensions (e.g., XTEST, XTrap, XTestExtension1). .TP 8 .B tty\fIxx\fP ignored, for servers started the ancient way (from init). .TP 8 .B v sets video-off screen-saver preference. .TP 8 .B \-v sets video-on screen-saver preference. .TP 8 .B \-wm forces the default backing-store of all windows to be WhenMapped. This is a backdoor way of getting backing-store to apply to all windows. Although all mapped windows will have backing store, the backing store attribute value reported by the server for a window will be the last value established by a client. If it has never been set by a client, the server will report the default value, NotUseful. This behavior is required by the X protocol, which allows the server to exceed the client's backing store expectations but does not provide a way to tell the client that it is doing so. .TP 8 .B \-x \fIextension\fP loads the specified extension at init. This is a no-op for most implementations. .SH SERVER DEPENDENT OPTIONS Some X servers accept the following options: .TP 8 .B \-ld \fIkilobytes\fP sets the data space limit of the server to the specified number of kilobytes. A value of zero makes the data size as large as possible. The default value of \-1 leaves the data space limit unchanged. .TP 8 .B \-lf \fIfiles\fP sets the number-of-open-files limit of the server to the specified number. A value is zero makes the limit as large as possible. The default value of \-1 leaves the limit unchanged. .TP 8 .B \-ls \fIkilobytes\fP sets the stack space limit of the server to the specified number of kilobytes. A value of zero makes the stack size as large as possible. The default value of \-1 leaves the stack space limit unchanged. .TP 8 .B \-logo turns on the X Window System logo display in the screen-saver. There is currently no way to change this from a client. .TP 8 .B nologo turns off the X Window System logo display in the screen-saver. There is currently no way to change this from a client. .SH XDMCP OPTIONS X servers that support XDMCP have the following options. See the \fIX Display Manager Control Protocol\fP specification for more information. .TP 8 .B \-query \fIhost-name\fP Enable XDMCP and send Query packets to the specified host. .TP 8 .B \-broadcast Enable XDMCP and broadcast BroadcastQuery packets to the network. The first responding display manager will be chosen for the session. .TP 8 .B \-indirect \fIhost-name\fP Enable XDMCP and send IndirectQuery packets to the specified host. .TP 8 .B \-port \fIport-num\fP Use an alternate port number for XDMCP packets. Must be specified before any \-query, \-broadcast or \-indirect options. .TP 8 .B \-class \fIdisplay-class\fP XDMCP has an additional display qualifier used in resource lookup for display-specific options. This option sets that value, by default it is "MIT-Unspecified" (not a very useful value). .TP 8 .B \-cookie \fIxdm-auth-bits\fP When testing XDM-AUTHENTICATION-1, a private key is shared between the server and the manager. This option sets the value of that private data (not that it is very private, being on the command line!). .TP 8 .B \-displayID \fIdisplay-id\fP Yet another XDMCP specific value, this one allows the display manager to identify each display so that it can locate the shared key. .SH XKEYBOARD OPTIONS X servers that support the XKEYBOARD extension accept the following options: .TP 8 .B \-xkbdir \fIdirectory\fP base directory for keyboard layout files .TP 8 .B \-xkbmap \fIfilename\fP keyboard description to load on startup .TP 8 .B [+-]accessx enable(+) or disable(-) AccessX key sequences .TP 8 .B \-ar1 \fImilliseconds\fP sets the length of time in milliseconds that a key must be depressed before autorepeat starts .TP 8 .B \-ar2 \fImilliseconds\fP sets the length of time in milliseconds that should elapse between autorepeat-generated keystrokes .PP Many servers also have device-specific command line options. See the manual pages for the individual servers for more details. .SH "NETWORK CONNECTIONS" The X server supports client connections via a platform-dependent subset of the following transport types: TCP\/IP, Unix Domain sockets, DECnet, and several varieties of SVR4 local connections. See the DISPLAY NAMES section of the \fIX(1)\fP manual page to learn how to specify which transport type clients should try to use. .SH SECURITY The X server implements a platform-dependent subset of the following authorization protocols: MIT-MAGIC-COOKIE-1, XDM-AUTHORIZATION-1, SUN-DES-1, and MIT-KERBEROS-5. See the \fIXsecurity(1)\fP manual page for information on the operation of these protocols. .PP Authorization data required by the above protocols is passed to the server in a private file named with the \fB\-auth\fP command line option. Each time the server is about to accept the first connection after a reset (or when the server is starting), it reads this file. If this file contains any authorization records, the local host is not automatically allowed access to the server, and only clients which send one of the authorization records contained in the file in the connection setup information will be allowed access. See the \fIXau\fP manual page for a description of the binary format of this file. See \fIxauth(1)\fP for maintenance of this file, and distribution of its contents to remote hosts. .PP The X server also uses a host-based access control list for deciding whether or not to accept connections from clients on a particular machine. If no other authorization mechanism is being used, this list initially consists of the host on which the server is running as well as any machines listed in the file \fI/etc/X\fBn\fI.hosts\fR, where \fBn\fP is the display number of the server. Each line of the file should contain either an Internet hostname (e.g. expo.lcs.mit.edu) or a DECnet hostname in double colon format (e.g. hydra::). There should be no leading or trailing spaces on any lines. For example: .sp .in +8 .nf joesworkstation corporate.company.com star:: bigcpu:: .fi .in -8 .PP Users can add or remove hosts from this list and enable or disable access control using the \fIxhost\fP command from the same machine as the server. .PP The X protocol intrinsically does not have any notion of window operation permissions or place any restrictions on what a client can do; if a program can connect to a display, it has full run of the screen. Sites that have better authentication and authorization systems might wish to make use of the hooks in the libraries and the server to provide additional security models. .SH SIGNALS The X server attaches special meaning to the following signals: .TP 8 .I SIGHUP This signal causes the server to close all existing connections, free all resources, and restore all defaults. It is sent by the display manager whenever the main user's main application (usually an \fIxterm\fP or window manager) exits to force the server to clean up and prepare for the next user. .TP 8 .I SIGTERM This signal causes the server to exit cleanly. .TP 8 .I SIGUSR1 This signal is used quite differently from either of the above. When the server starts, it checks to see if it has inherited SIGUSR1 as SIG_IGN instead of the usual SIG_DFL. In this case, the server sends a SIGUSR1 to its parent process after it has set up the various connection schemes. \fIXdm\fP uses this feature to recognize when connecting to the server is possible. .SH FONTS The X server can obtain fonts from directories and/or from font servers. The list of directories and font servers the X server uses when trying to open a font is controlled by the \fIfont path\fP. .LP The default font path is "/lib/X11/fonts/misc/, /lib/X11/fonts/Speedo/, /lib/X11/fonts/Type1/, /lib/X11/fonts/75dpi/, /lib/X11/fonts/100dpi/\" . where refers to the root of the X11 install tree. .LP The font path can be set with the \fB\-fp\fP option or by \fIxset(1)\fP after the server has started. .SH FILES .TP 30 /etc/X\fBn\fP.hosts Initial access control list for display number \fBn\fP .TP 30 /lib/X11/fonts/misc, /lib/X11/fonts/75dpi, /lib/X11/fonts/100dpi Bitmap font directories .TP 30 /lib/X11/fonts/Speedo, /lib/X11/fonts/Type1 Outline font directories .TP 30 /lib/X11/fonts/PEX PEX font directories .TP 30 /lib/X11/rgb.txt Color database .TP 30 /tmp/.X11-unix/X\fBn\fP Unix domain socket for display number \fBn\fP .TP 30 /tmp/rcX\fBn\fP Kerberos 5 replay cache for display number \fBn\fP .TP 30 /usr/adm/X\fBn\fPmsgs Error log file for display number \fBn\fP if run from \fIinit(8)\fP .TP 30 /lib/X11/xdm/xdm-errors Default error log file if the server is run from \fIxdm(1)\fP .LP Note: refers to the root of the X11 install tree. .SH "SEE ALSO" General information: X(1) .PP Protocols: .I "X Window System Protocol," .I "The X Font Service Protocol," .I "X Display Manager Control Protocol" .PP Fonts: bdftopcf(1), mkfontdir(1), xfs(1), xlsfonts(1), xfontsel(1), xfd(1), .I "X Logical Font Description Conventions" .PP Security: Xsecurity(1), xauth(1), Xau(1), xdm(1), xhost(1) .PP Starting the server: xdm(1), xinit(1) .PP Controlling the server once started: xset(1), xsetroot(1), xhost(1) .PP Server-specific man pages: Xdec(1), XmacII(1), Xsun(1), Xnest(1), Xvfb(1), XF86_Acc(1), XF86_Mono(1), XF86_SVGA(1), XF86_VGA16(1), XFree86(1) .PP Server internal documentation: .I "Definition of the Porting Layer for the X v11 Sample Server," .I "Strategies for Porting the X v11 Sample Server," .I "Godzilla's Guide to Porting the X V11 Sample Server" .SH AUTHORS The sample server was originally written by Susan Angebranndt, Raymond Drewry, Philip Karlton, and Todd Newman, from Digital Equipment Corporation, with support from a large cast. It has since been extensively rewritten by Keith Packard and Bob Scheifler, from MIT.