Xvfb.man (5498B)
1 .\" $XdotOrg: xc/programs/Xserver/hw/vfb/Xvfb.man,v 1.3 2005/03/23 20:49:52 gisburn Exp $ 2 .\" $Xorg: Xvfb.man,v 1.4 2001/02/09 02:04:45 xorgcvs Exp $ 3 .\" Copyright 1993, 1998 The Open Group 4 .\" 5 .\" Permission to use, copy, modify, distribute, and sell this software and its 6 .\" documentation for any purpose is hereby granted without fee, provided that 7 .\" the above copyright notice appear in all copies and that both that 8 .\" copyright notice and this permission notice appear in supporting 9 .\" documentation. 10 .\" 11 .\" The above copyright notice and this permission notice shall be included 12 .\" in all copies or substantial portions of the Software. 13 .\" 14 .\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 15 .\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 16 .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 17 .\" IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 .\" OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 .\" ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 .\" OTHER DEALINGS IN THE SOFTWARE. 21 .\" 22 .\" Except as contained in this notice, the name of The Open Group shall 23 .\" not be used in advertising or otherwise to promote the sale, use or 24 .\" other dealings in this Software without prior written authorization 25 .\" from The Open Group. 26 .\" 27 .\" $XFree86: xc/programs/Xserver/hw/vfb/Xvfb.man,v 1.9 2001/12/14 19:59:45 dawes Exp $ 28 .\" 29 .TH XVFB 1 @xorgversion@ 30 .SH NAME 31 Xvfb \- virtual framebuffer X server for X Version 11 32 .SH SYNOPSIS 33 .B Xvfb 34 [ option ] ... 35 .SH DESCRIPTION 36 .I Xvfb 37 is an X server that can run on machines with no display hardware 38 and no physical input devices. It emulates a dumb framebuffer using 39 virtual memory. 40 .PP 41 The primary use of this server was intended to be server testing. The 42 fb code for any depth can be exercised with this server 43 without the need for real hardware that supports the desired depths. 44 The X community has found many other novel uses for \fIXvfb\fP, 45 including testing clients against unusual depths and screen 46 configurations, doing batch processing with \fIXvfb\fP as a background 47 rendering engine, load testing, as an aid to porting the X server to a 48 new platform, and providing an unobtrusive way to run applications 49 that don't really need an X server but insist on having one anyway. 50 .SH OPTIONS 51 .PP 52 In addition to the normal server options described in the \fIXserver(1)\fP 53 manual page, \fIXvfb\fP accepts the following command line switches: 54 .TP 4 55 .B "\-screen \fIscreennum\fP \fIWxHxD\fP" 56 This option creates screen \fIscreennum\fP and sets its width, height, 57 and depth to W, H, and D respectively. By default, only screen 0 exists 58 and has the dimensions 1280x1024x24. 59 .TP 4 60 .B "\-pixdepths \fIlist-of-depths\fP" 61 This option specifies a list of pixmap depths that the server should 62 support in addition to the depths implied by the supported screens. 63 \fIlist-of-depths\fP is a space-separated list of integers that can 64 have values from 1 to 32. 65 .TP 4 66 .B "\-fbdir \fIframebuffer-directory\fP" 67 This option specifies the directory in which the memory mapped files 68 containing the framebuffer memory should be created. 69 See FILES. 70 This option only exists on machines that have the mmap and msync system 71 calls. 72 .TP 4 73 .B "\-shmem" 74 This option specifies that the framebuffer should be put in shared memory. 75 The shared memory ID for each screen will be printed by the server. 76 The shared memory is in xwd format. 77 This option only exists on machines that support the System V shared memory 78 interface. 79 .PP 80 If neither \fB\-shmem\fP nor \fB\-fbdir\fP is specified, 81 the framebuffer memory will be allocated with malloc(). 82 .TP 4 83 .B "\-linebias \fIn\fP" 84 This option specifies how to adjust the pixelization of thin lines. 85 The value \fIn\fP is a bitmask of octants in which to prefer an axial 86 step when the Bresenham error term is exactly zero. See the file 87 Xserver/mi/miline.h for more information. This option is probably only useful 88 to server developers to experiment with the range of line pixelization 89 possible with the fb code. 90 .TP 4 91 .B "\-blackpixel \fIpixel-value\fP, \-whitepixel \fIpixel-value\fP" 92 These options specify the black and white pixel values the server should use. 93 .SH FILES 94 The following files are created if the \-fbdir option is given. 95 .TP 4 96 \fIframebuffer-directory\fP/Xvfb_screen<n> 97 Memory mapped file containing screen n's framebuffer memory, one file 98 per screen. The file is in xwd format. Thus, taking a full-screen 99 snapshot can be done with a file copy command, and the resulting 100 snapshot will even contain the cursor image. 101 .SH EXAMPLES 102 .TP 8 103 Xvfb :1 -screen 0 1600x1200x24 104 The server will listen for connections as server number 1, and screen 0 105 will be depth 24 1600x1200. 106 .TP 8 107 Xvfb :1 -screen 1 1600x1200x16 108 The server will listen for connections as server number 1, screen 0 will have the 109 default screen configuration (1280x1024x24), and screen 1 will be depth 16 1600x1200. 110 .TP 8 111 Xvfb -pixdepths 3 27 -fbdir /var/tmp 112 The server will listen for connections as server number 0, will have the 113 default screen configuration (one screen, 1280x1024x24), 114 will also support pixmap 115 depths of 3 and 27, 116 and will use memory mapped files in /var/tmp for the framebuffer. 117 .TP 8 118 xwud -in /var/tmp/Xvfb_screen0 119 Displays screen 0 of the server started by the preceding example. 120 .SH "SEE ALSO" 121 .PP 122 X(@miscmansuffix@), Xserver(1), xwd(1), xwud(1), XWDFile.h 123 .SH AUTHORS 124 David P. Wiggins, The Open Group, Inc.