1FbTerm(1) FbTerm User Manual FbTerm(1)
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6 FbTerm - a fast Frame Buffer based TERMinal emulator for linux
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9 fbterm [options] [--] [command [arguments]]
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12 FbTerm is a fast terminal emulator for linux with frame buffer device
13 or VESA video card. Features include:
14 * mostly as fast as terminal of linux kernel while accelerated
16 scrolling is enabled
17 * select font with fontconfig and draw text with freetype2, same as
18 Qt/Gtk+ based GUI apps
19 * dynamically create/destroy up to 10 windows initially running
20 default shell
21 * record scroll-back history for every window
22 * auto-detect current locale and convert text encoding, support dou‐
23 ble width scripts like Chinese, Japanese etc
24 * switch between configurable additional text encodings with hot keys
25 on the fly
26 * copy/past selected text between windows with mouse when gpm server
27 is running
28 * change the orientation of screen display, a.k.a. screen rotation
29 * lightweight input method framework with client-server architecture
30 * background image for eye candy
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33 command [arguments] may be given to override the built-in choice of
34 shell program. Normally FbTerm checks the SHELL variable. If that is
35 not set, it tries to use the user's login shell program specified in
36 the password file. If that is not set, /bin/sh will be used. You should
37 use the -- argument to separate FbTerm's options from the arguments
38 supplied to the command.
39 FbTerm first uses option value specified in command line arguments,
41 then in the configure file $HOME/.fbtermrc. If that file doesn't
42 exist, FbTerm will create it with default options on startup.
43 -h, --help
45 display the help and exit
46 -V, --version
48 display FbTerm version and exit
49 -v, --verbose
51 display extra FbTerm's information
52 -n, --font-names=text
54 specify font family names
55 -s, --font-size=num
57 specify font pixel size
58 --font-width=num
60 force font width
61 --font-height=num
63 force font height
64 -f, --color-foreground=num
66 specify foreground color
67 -b, --color-background=num
69 specify background color
70 -e, --text-encodings=text
72 specify additional text encodings
73 -a, --ambiguous-wide
75 treat ambiguous width characters as wide
76 -r, --screen-rotate=num
78 specify the orientation of screen display
79 -i, --input-method=text
81 specify input method program
82 --cursor-shape=num
84 specify default cursor shape
85 --cursor-interval=num
87 specify cursor flash interval
88 --vesa-mode=num
90 specify VESA video mode
91 --vesa-mode=list
93 display available VESA video modes
94 see comments in $HOME/.fbtermrc for details of these options.
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99 keyboard:
100 CTRL_ALT_E: exit from FbTerm
101 CTRL_ALT_C: create a new window
102 CTRL_ALT_D: destroy current window
103 CTRL_ALT_1: switch to window 1
104 CTRL_ALT_2: switch to window 2
105 CTRL_ALT_3: switch to window 3
106 CTRL_ALT_4: switch to window 4
107 CTRL_ALT_5: switch to window 5
108 CTRL_ALT_6: switch to window 6
109 CTRL_ALT_7: switch to window 7
110 CTRL_ALT_8: switch to window 8
111 CTRL_ALT_9: switch to window 9
112 CTRL_ALT_0: switch to window 10
113 SHIFT_LEFT: switch to previous window
114 SHIFT_RIGHT: switch to next window
115 SHIFT_PAGEUP: history scroll up
116 SHIFT_PAGEDOWN: history scroll down
117 CTRL_ALT_F1: switch to encoding of current locale
118 CTRL_ALT_F2 to CTRL_ALT_F6: switch to additional encodings
119 CTRL_SPACE: toggle input method
120 CTRL_ALT_K: kill input method server
121 mouse:
123 move when left button down: select text
124 double click with left button: auto select text
125 click with right button: paste selected text
126 Sometimes above actions will not work, please try to redo them with
128 shift key holding down.
129
131 Before executing FbTerm, make sure there is a frame buffer device in
132 your system, and you have read/write access right with it. Normally
133 FbTerm tries to open /dev/fb0 and /dev/fb/0, environment variable
134 "FRAMEBUFFER" may be used to override this built-in behavior.
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137 From version 1.6, FbTerm adds VESA video card support. By default,
138 FbTerm tries frame buffer device first, if failure, then tries to use
139 VESA device with highest resolution and color depth. option "vesa-mode"
140 may be given to force only open VESA device with the specified video
141 mode. To see available video modes for your VESA card, execute "fbterm
142 --vesa-mode=list".
143 Attention: 1) VESA support requires root privilege to work; 2) do not
145 force to use VESA device on the system with frame buffer device
146 enabled, they maybe conflict with each other.
147
149 FbTerm invokes fontconfig to get a font list, if the first font doesn't
150 contain the glyph for the rendering character, it will try second font,
151 then the third, ... and so on, user can see this ordered font list with
152 "fbterm -v".
153 If you don't like the fonts selected by FbTerm, execute "fc-list" to
155 get available fonts, choose favorites as the value of option "font-
156 names". You may also modify the configure file of fontconfig, which
157 will change the behavior of all programs based on fontconfig!
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160 By using iconv, FbTerm converts other encodings to internal encoding
161 UTF-8. On startup, FbTerm checks variable LC_CTYPE to determine the
162 default text encoding, which is binded to shortcut CTRL_ALT_F1. User
163 can specify up to 5 additional encodings with option "text-encodings",
164 for example, as a Chinese user, you set "text-encodings=gbk,big5",
165 shortcut CTRL_ALT_F2 will bind to gbk, and CTRL_ALT_F3 bind to big5.
166 In a number of CJK encodings there are ambiguous width characters which
168 have a width of either narrow or wide depending on the context of their
169 use. By default, FbTerm treats them as narrow width characters, option
170 "ambiguous-wide" may be used to change the behavior.
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173 FbTerm doesn't load and parse any image file with various formats
174 directly, instead it takes a screen shot of frame buffer device on
175 startup if variable FBTERM_BACKGROUND_IMAGE is defined, then uses this
176 screen shot as the background for text rendering. In order to enable
177 background image support, user should first put a image to frame buffer
178 device with a image viewer. A wrapper script using fbv is listed below:
179 #!/bin/bash
181 # fbterm-bi: a wrapper script to enable background image with
183 fbterm
184 # usage: fbterm-bi /path/to/image fbterm-options
185 echo -ne "\e[?25l" # hide cursor
187 fbv -ciuker "$1" << EOF
189 q
190 EOF
191 shift
193 export FBTERM_BACKGROUND_IMAGE=1
194 exec fbterm "$@"
195 Attention: 1) do not enable background image on frame buffer device
197 with 8bpp depth, because FbTerm changes color map table for correct
198 text rendering; 2) if the screen shot is different from the original
199 image, try to use a fast scrolling disabled frame buffer device.
200
202 FbTerm supports xterm's 256 color mode extension. The first 16 colors
203 are the default terminal colors. Additionally, there's a 6x6x6 color
204 cube, and 24 grayscale tones. But xterm's 256 color escape sequences
205 conflict with the linux sequences implemented by FbTerm, so private
206 escape sequences were introduced to support this feature:
207 ESC [ 1 ; n } set foreground color to n (0 - 255)
209 ESC [ 2 ; n } set background color to n (0 - 255)
210 ESC [ 3 ; n ; r ; g ; b } set color n to (r, g, b) , n, r,
211 g, b all in (0 - 255)
212 A new terminfo database entry named "fbterm" was added to use these
214 private sequences, all program based on terminfo should work with it.
215 By default, FbTerm sets environment variable "TERM" to value "linux",
216 user need run "TERM=fbterm /path/to/program" to enable 256 color mode.
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219 Instead of adding input method directly in FbTerm, a client-server
220 based input method framework is designed to do this work. FbTerm acts
221 as a client, standalone IM program as a server, and they run in sepa‐
222 rated processes.
223 As a normal IM user, you should install a IM program written for
225 FbTerm, and specify it as the value of option "input-method".
226 CTRL_SPACE is the shortcut to activate/deactivate input method. And
227 CTRL_ALT_K may be used to kill the IM program when it has freezed.
228
231 FbTerm tries to change linux kernel key map table to setup shortcuts,
232 which requires SYS_TTY_CONFIG capability since kernel version 2.6.15.
233 It means FbTerm should be a setuid 0 program to allow non-root users to
234 use shortcuts. FbTerm only switches to root privilege temporarily when
235 changing key map table, we believe it's pretty much free from security
236 problems. If you really don't like this and have a linux kernel with
237 file system capabilities enabled, which allow user to give binaries a
238 subset of root's powers without using setuid 0 (official kernel 2.6.27
239 includes it), you can run command "sudo setcap 'cap_sys_tty_config+ep'
240 /path/to/fbterm".
241 FbTerm redirects /dev/tty0 output to the pseudo terminal of current
243 sub-window. In linux before version 2.6.10, anybody can do this as long
244 as the output was not redirected yet; since version 2.6.10, only root
245 or a process with the CAP_SYS_ADMIN capability may do this. You should
246 do similar work with above ones for FbTerm to enable this feature for
247 non-root users.
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251 According test result, FbTerm spends more than 95% time on painting
252 screen. Speedup painting will significantly increase performance. Here
253 are some suggestions for frame buffer device:
254 * Enable fast scrolling on frame buffer device. The visible screen
256 will be just a window of the video memory, when scrolling, FbTerm only
257 change the start of window, no need to repaint the whole screen.
258 * On Intel P6 family processors the Memory Type Range Registers
260 (MTRRs) may be used to control processor access to memory ranges. If
261 you have video card on a PCI or AGP bus, enabling write-combining
262 allows bus write transfers to be combined into a larger transfer before
263 bursting over the PCI/AGP bus. This can increase performance of
264 FbTerm's paint operations.
265 Maybe you need to enable them manually for your video card. For exam‐
267 ple, by default fast scrolling and write-combining are all disabled on
268 general VESA frame buffer device, GRUB/LILO configure file should be
269 modified to enable them. A GRUB example is showed below:
270 title Ubuntu
272 root (hd0,0)
273 kernel /boot/vmlinuz ro root=LABEL=UBUNTU splash vga=0x317
274 video=vesafb:ywrap,mtrr:3
275 initrd /boot/initrd.img
276 You may check fast scrolling status with "fbterm -v", a message with
278 "scrolling: redraw" means fast scrolling is disabled, otherwise
279 enabled.
280
282 Written by dragchan.
283
285 Please submit bug reports to <http://code.google.com/p/fbterm/issues>.
286
288 Copyright © 2008-2010 dragchan. License GPLv2: GNU GPL version 2 or
289 later <http://gnu.org/licenses/gpl.html>.
290 This is free software: you are free to change and redistribute it.
291 There is NO WARRANTY, to the extent permitted by law.
292FbTerm 1.7 October 2010 FbTerm(1)