.\" .\" Copyright 1991, 1998 The Open Group .\" .\" Permission to use, copy, modify, distribute, and sell this software and its .\" documentation for any purpose is hereby granted without fee, provided that .\" the above copyright notice appear in all copies and that both that .\" copyright notice and this permission notice appear in supporting .\" documentation. .\" .\" 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. 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Network Computing Devices make .\" no representations about the .\" suitability of this software for any purpose. It is provided "as is" .\" without express or implied warranty. .TH xfs __appmansuffix__ __xorgversion__ .SH NAME xfs \- X font server .SH SYNOPSIS .B xfs [ .BI "\-config " configuration_file ] [ .B \-daemon ] [ .B \-droppriv ] [ .B \-inetd ] [ .BI "\-ls " listen_socket ] [ .B \-nodaemon ] [ .BI "\-port " tcp_port ] [ .BI "\-user " username ] .SH DESCRIPTION .B xfs is the X Window System font server. It supplies fonts to X Window System display servers. The server is usually run by a system administrator, and started via .BR init (__adminmansuffix__) or .BR inetd (__adminmansuffix__). Users may also wish to start private font servers for specific sets of fonts. .PP To connect to a font server, see the documentation for your X server; it likely supports the syntax documented in the \(lqFONT SERVER NAMES\(rq section of .BR X (__miscmansuffix__). .SH OPTIONS .TP .BI "\-config " configuration_file specifies the configuration file .B xfs will use. If this parameter is not specified, xfs will read its configuration from __configfiledesc__ .IR __configfilepath__ . .TP .B \-daemon instructs .B xfs to fork and go into the background automatically at startup. If this option is not specified, .B xfs will run as a regular process (unless it was built to daemonize by default). When running as a daemon, .B xfs will attempt to create a file in which it stores its process ID, and will delete that file upon exit; .TP .B \-droppriv instructs .B xfs to attempt to run as user and group .I xfs (unless the .B \-user option is used). This has been implemented for security reasons, as .B xfs may have undiscovered buffer overflows or other paths for possible exploit, both local and remote. When using this option, you may also wish to specify \(oqno\-listen = tcp\(cq in the config file, which ensures that .B xfs will not to use a TCP port at all. By default, .B xfs runs with the user and group IDs of the user who invoked it. .TP .B \-inetd informs .B xfs that it is being started by inetd, and that a listening socket on the appropriate port is being passed as standard input. Assumes that inetd is configured to "wait" mode, and will thus allow xfs to handle listening for and accepting further connections on this port. This allows xfs to be started on demand when the first font client connects. When using this option, the -daemon and -port flags are ignored. .TP .BI "\-ls " listen_socket specifies a file descriptor which is already set up to be used as the listen socket. This option is only intended to be used by the font server itself when automatically spawning another copy of itself to handle additional connections. .TP .B \-nodaemon instructs .B xfs not to daemonize (fork and detach from its controlling terminal). This option only has an effect if .B xfs is built to daemonize by default, which is not the stock configuration. .TP .BI "\-port " tcp_port specifies the TCP port number on which the server will listen for connections. The default port number is 7100. This option is ignored if .B xfs is configured to not listen to TCP transports at all (see \(lqConfiguration File Format\(rq below). .TP .BI "\-user " username instructs .B xfs to run as the user .IR username. See .B \-droppriv for why this may be desired. By default, .B xfs runs with the user and group IDs of the user who invoked it. .SH "INPUT FILES" .B xfs reads and serves any font file format recognized by the X server itself. It locates font files through the specification of a .IR catalogue , which is declared in .BR xfs 's configuration file. .SS "Configuration File Format" .B xfs reads its configuration from a text file (see the .B \-config option in the \(lqOPTIONS\(rq section above). The configuration language is a list of keyword and value pairs. Each keyword is followed by an equals sign (\(oq=\(cq) and then the desired value. .PP Recognized keywords include: .TP .BR alternate\-servers " (list of \fIstring\fPs)" lists alternate servers for this font server. See the \(lqFONT SERVER NAMES\(rq section of .BR X (__miscmansuffix__) for the syntax of the string. .\" .TP .\" .BR cache\-size " (\fIcardinal\fP)" .\" determines the size (in bytes) of the font server cache. .TP .BR catalogue " (list of \fIstring\fPs)" declares as ordered list of font path element names from which fonts will be served. The current implementation only supports a single catalogue ("all") containing all of the specified fonts. A special directory with symlinks to font paths can be specified using a catalogue: entry. See the CATALOGUE DIR section below for details. .TP .BR client\-limit " (\fIcardinal\fP)" determines the number of clients this font server will support before refusing service. This is useful for tuning the load on each individual font server. .TP .BR clone\-self " (\fIboolean\fP)" indicates whether this font server should attempt to clone itself when the number of connected clients reaches the .BR client\-limit . .TP .BR default\-point\-size " (\fIcardinal\fP)" The default pointsize (in decipoints) for font requests that don't specify a point size. The default is 120. .TP .BR default\-resolutions " (list of \fIresolution\fPs)" indicates the resolutions the server supports by default. This information may be used as a hint for pre-rendering, and substituted into requests for scaled fonts which do not specify a resolution. A .I resolution is a comma-separated pair of horizontal and vertical resolutions in pixels per inch. Multiple resolutions are separated by commas. .TP .BR deferglyphs " (\fIstring\fP)" sets the mode for delayed fetching and caching of glyphs. .I string should be one of \(oqnone\(cq, meaning glyphs deferment is disabled, \(oqall\(cq, meaning it is enabled for all fonts, and \(oq16\(cq, meaning it is enabled only for 16-bit fonts. .TP .BR error\-file " (\fIstring\fP)" indicates the filename of the error file. All warnings and errors will be logged here, unless .B use\-syslog is set to a true value (see below). .TP .BR no\-listen " (\fItrans-type\fP)" disables the specified transport type. For example, TCP/IP connections can be disabled with \(oqno\-listen = tcp\(cq. .TP .BR port " (\fIcardinal\fP)" indicates the TCP port on which the server will listen for connections. .\" .TP .\" .BR trusted-clients " (list of \fIstring\fPs)" .\" identifies the clients the font server will talk to. .\" Others will be refused for the initial connection. .\" An empty list means the server will talk to any client. .TP .BR use\-syslog " (\fIboolean\fP)" determines whether errors and diagnostics should be reported via .BR syslog (__libmansuffix__) (on supported systems) instead of being written to the .B error\-file (see above). .SH "CATALOGUE DIR" You can specify a special kind of font path in the form \fBcatalogue:\fR. The directory specified after the catalogue: prefix will be scanned for symlinks and each symlink destination will be added as a local fontfile FPE. .PP The symlink can be suffixed by attributes such as '\fBunscaled\fR', which will be passed through to the underlying fontfile FPE. The only exception is the newly introduced '\fBpri\fR' attribute, which will be used for ordering the font paths specified by the symlinks. An example configuration: .nf 75dpi:unscaled:pri=20 \-> /usr/share/X11/fonts/75dpi ghostscript:pri=60 \-> /usr/share/fonts/default/ghostscript misc:unscaled:pri=10 \-> /usr/share/X11/fonts/misc type1:pri=40 \-> /usr/share/X11/fonts/Type1 type1:pri=50 \-> /usr/share/fonts/default/Type1 .fi This will add /usr/share/X11/fonts/misc as the first FPE with the attribute 'unscaled', second FPE will be /usr/share/X11/fonts/75dpi, also with the attribute unscaled etc. This is functionally equivalent to setting the following font path: .nf /usr/share/X11/fonts/misc:unscaled, /usr/share/X11/fonts/75dpi:unscaled, /usr/share/X11/fonts/Type1, /usr/share/fonts/default/Type1, /usr/share/fonts/default/ghostscript .fi .SS "Example Configuration File" .nf # # sample font server configuration file # # allow a max of 10 clients to connect to this font server. client\-limit = 10 # When a font server reaches the above limit, start up a new one. clone\-self = on # Identify alternate font servers for clients to use. alternate\-servers = hansen:7101,hansen:7102 # Look for fonts in the following directories. The first is a set of # TrueType outlines, the second is a set of misc bitmaps (such as terminal # and cursor fonts), and the last is a set of 100dpi bitmaps. # catalogue = /usr/share/X11/fonts/TTF, /usr/share/X11/fonts/misc, /usr/share/X11/fonts/100dpi/ # in 12 points, decipoints default\-point\-size = 120 # 100 x 100 and 75 x 75 default\-resolutions = 100,100,75,75 # Specify our log filename. error\-file = /var/log/xfs.log # Direct diagnostics to our own log file instead of using syslog. use\-syslog = off .fi .SH "OUTPUT FILES" When operating in daemon mode, .B xfs sends diagnostic messages (errors and warnings) to the log file specified by the .B error-file configuration variable by default. However, these messages can be sent to an alternate location via the .B error\-file and .B use\-syslog configuration variables; see \(lqConfiguration File Format\(rq, above. .SH "ASYNCHRONOUS EVENTS" .B xfs handles the following signals specially: .TP .I SIGTERM causes the font server to exit cleanly. .TP .I SIGUSR1 causes .B xfs to re-read its configuration file. .TP .I SIGUSR2 causes .B xfs to flush any cached data it may have. .TP .I SIGHUP causes .B xfs to reset, closing all active connections and re-reading the configuration file. .SH BUGS Multiple catalogues should be supported. .SH "FUTURE DIRECTIONS" Significant further development of .B xfs is unlikely. One of the original motivations behind it was the single-threaded nature of the X server \(em a user's X session could seem to \(oqfreeze up\(cq while the X server took a moment to rasterize a font. This problem with the X server, which remains single-threaded in all popular implementations to this day, has been mitigated on two fronts: machines have gotten much faster, and client-side font rendering (particularly via the Xft library) is the norm in contemporary software. .SH AUTHORS Dave Lemke, Network Computing Devices, Inc .br Keith Packard, Massachusetts Institute of Technology .SH "SEE ALSO" .BR X (__miscmansuffix__), .BR xfsinfo (__appmansuffix__), .BR fslsfonts (__appmansuffix__), .BR init (__adminmansuffix__), .BR inetd (__adminmansuffix__), .BR syslog (__libmansuffix__), .IR "The X Font Service Protocol" , .I Font Server Implementation Overview