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Revision: 1.71
Committed: Wed Dec 31 14:40:24 2014 UTC (9 years, 4 months ago) by root
Branch: MAIN
CVS Tags: rxvt-unicode-rel-9_21
Changes since 1.70: +20 -0 lines
Log Message:
cvvis faq

File Contents

# User Rev Content
1 root 1.42 RXVT-UNICODE/URXVT FREQUENTLY ASKED QUESTIONS
2     Meta, Features & Commandline Issues
3     My question isn't answered here, can I ask a human?
4     Before sending me mail, you could go to IRC: "irc.freenode.net", channel
5     "#rxvt-unicode" has some rxvt-unicode enthusiasts that might be
6     interested in learning about new and exciting problems (but not FAQs :).
7    
8 root 1.56 I use Gentoo, and I have a problem...
9 root 1.70 There are two big problems with Gentoo Linux: first, most if not all
10     Gentoo systems are completely broken (missing or mismatched header
11     files, broken compiler etc. are just the tip of the iceberg); secondly,
12     it should be called Gentoo GNU/Linux.
13 root 1.56
14     For these reasons, it is impossible to support rxvt-unicode on Gentoo.
15     Problems appearing on Gentoo systems will usually simply be ignored
16     unless they can be reproduced on non-Gentoo systems.
17    
18 root 1.42 Does it support tabs, can I have a tabbed rxvt-unicode?
19     Beginning with version 7.3, there is a perl extension that implements a
20     simple tabbed terminal. It is installed by default, so any of these
21     should give you tabs:
22    
23     urxvt -pe tabbed
24    
25     URxvt.perl-ext-common: default,tabbed
26    
27     It will also work fine with tabbing functionality of many window
28     managers or similar tabbing programs, and its embedding-features allow
29     it to be embedded into other programs, as witnessed by doc/rxvt-tabbed
30     or the upcoming "Gtk2::URxvt" perl module, which features a tabbed urxvt
31     (murxvt) terminal as an example embedding application.
32    
33     How do I know which rxvt-unicode version I'm using?
34     The version number is displayed with the usage (-h). Also the escape
35     sequence "ESC [ 8 n" sets the window title to the version number. When
36     using the urxvtc client, the version displayed is that of the daemon.
37    
38     Rxvt-unicode uses gobs of memory, how can I reduce that?
39     Rxvt-unicode tries to obey the rule of not charging you for something
40     you don't use. One thing you should try is to configure out all settings
41     that you don't need, for example, Xft support is a resource hog by
42     design, when used. Compiling it out ensures that no Xft font will be
43     loaded accidentally when rxvt-unicode tries to find a font for your
44     characters.
45    
46     Also, many people (me included) like large windows and even larger
47     scrollback buffers: Without "--enable-unicode3", rxvt-unicode will use 6
48     bytes per screen cell. For a 160x?? window this amounts to almost a
49     kilobyte per line. A scrollback buffer of 10000 lines will then (if
50     full) use 10 Megabytes of memory. With "--enable-unicode3" it gets
51     worse, as rxvt-unicode then uses 8 bytes per screen cell.
52    
53     How can I start urxvtd in a race-free way?
54     Try "urxvtd -f -o", which tells urxvtd to open the display, create the
55     listening socket and then fork.
56    
57 root 1.45 How can I start urxvtd automatically when I run urxvtc?
58 root 1.42 If you want to start urxvtd automatically whenever you run urxvtc and
59     the daemon isn't running yet, use this script:
60    
61     #!/bin/sh
62     urxvtc "$@"
63     if [ $? -eq 2 ]; then
64     urxvtd -q -o -f
65     urxvtc "$@"
66     fi
67    
68     This tries to create a new terminal, and if fails with exit status 2,
69     meaning it couldn't connect to the daemon, it will start the daemon and
70     re-run the command. Subsequent invocations of the script will re-use the
71     existing daemon.
72    
73 sf-exg 1.59 How do I distinguish whether I'm running rxvt-unicode or a regular
74     xterm? I need this to decide about setting colours etc.
75 root 1.42 The original rxvt and rxvt-unicode always export the variable
76     "COLORTERM", so you can check and see if that is set. Note that several
77     programs, JED, slrn, Midnight Commander automatically check this
78 sf-exg 1.59 variable to decide whether or not to use colour.
79 root 1.42
80     How do I set the correct, full IP address for the DISPLAY variable?
81     If you've compiled rxvt-unicode with DISPLAY_IS_IP and have enabled
82     insecure mode then it is possible to use the following shell script
83     snippets to correctly set the display. If your version of rxvt-unicode
84     wasn't also compiled with ESCZ_ANSWER (as assumed in these snippets)
85     then the COLORTERM variable can be used to distinguish rxvt-unicode from
86     a regular xterm.
87    
88     Courtesy of Chuck Blake <cblake@BBN.COM> with the following shell script
89     snippets:
90    
91     # Bourne/Korn/POSIX family of shells:
92     [ ${TERM:-foo} = foo ] && TERM=xterm # assume an xterm if we don't know
93     if [ ${TERM:-foo} = xterm ]; then
94     stty -icanon -echo min 0 time 15 # see if enhanced rxvt or not
95 root 1.67 printf "\eZ"
96 root 1.42 read term_id
97     stty icanon echo
98     if [ ""${term_id} = '^[[?1;2C' -a ${DISPLAY:-foo} = foo ]; then
99 root 1.67 printf '\e[7n' # query the rxvt we are in for the DISPLAY string
100     read DISPLAY # set it in our local shell
101 root 1.42 fi
102     fi
103    
104     How do I compile the manual pages on my own?
105     You need to have a recent version of perl installed as /usr/bin/perl,
106 root 1.49 one that comes with pod2man, pod2text and pod2xhtml (from Pod::Xhtml).
107 root 1.48 Then go to the doc subdirectory and enter "make alldoc".
108 root 1.42
109     Isn't rxvt-unicode supposed to be small? Don't all those features bloat?
110     I often get asked about this, and I think, no, they didn't cause extra
111     bloat. If you compare a minimal rxvt and a minimal urxvt, you can see
112     that the urxvt binary is larger (due to some encoding tables always
113     being compiled in), but it actually uses less memory (RSS) after
114     startup. Even with "--disable-everything", this comparison is a bit
115     unfair, as many features unique to urxvt (locale, encoding conversion,
116     iso14755 etc.) are already in use in this mode.
117    
118     text data bss drs rss filename
119     98398 1664 24 15695 1824 rxvt --disable-everything
120     188985 9048 66616 18222 1788 urxvt --disable-everything
121    
122     When you "--enable-everything" (which *is* unfair, as this involves xft
123     and full locale/XIM support which are quite bloaty inside libX11 and my
124 root 1.43 libc), the two diverge, but not unreasonably so.
125 root 1.42
126     text data bss drs rss filename
127     163431 2152 24 20123 2060 rxvt --enable-everything
128     1035683 49680 66648 29096 3680 urxvt --enable-everything
129    
130     The very large size of the text section is explained by the east-asian
131     encoding tables, which, if unused, take up disk space but nothing else
132     and can be compiled out unless you rely on X11 core fonts that use those
133     encodings. The BSS size comes from the 64k emergency buffer that my c++
134     compiler allocates (but of course doesn't use unless you are out of
135     memory). Also, using an xft font instead of a core font immediately adds
136     a few megabytes of RSS. Xft indeed is responsible for a lot of RSS even
137     when not used.
138    
139     Of course, due to every character using two or four bytes instead of
140     one, a large scrollback buffer will ultimately make rxvt-unicode use
141     more memory.
142    
143     Compared to e.g. Eterm (5112k), aterm (3132k) and xterm (4680k), this
144     still fares rather well. And compared to some monsters like
145     gnome-terminal (21152k + extra 4204k in separate processes) or konsole
146     (22200k + extra 43180k in daemons that stay around after exit, plus half
147     a minute of startup time, including the hundreds of warnings it spits
148     out), it fares extremely well *g*.
149    
150     Why C++, isn't that unportable/bloated/uncool?
151     Is this a question? :) It comes up very often. The simple answer is: I
152     had to write it, and C++ allowed me to write and maintain it in a
153     fraction of the time and effort (which is a scarce resource for me). Put
154     even shorter: It simply wouldn't exist without C++.
155    
156     My personal stance on this is that C++ is less portable than C, but in
157     the case of rxvt-unicode this hardly matters, as its portability limits
158     are defined by things like X11, pseudo terminals, locale support and
159     unix domain sockets, which are all less portable than C++ itself.
160    
161     Regarding the bloat, see the above question: It's easy to write programs
162 root 1.62 in C that use gobs of memory, and certainly possible to write programs
163     in C++ that don't. C++ also often comes with large libraries, but this
164     is not necessarily the case with GCC. Here is what rxvt links against on
165     my system with a minimal config:
166 root 1.42
167     libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
168     libc.so.6 => /lib/libc.so.6 (0x00002aaaaadde000)
169     libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab01d000)
170     /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
171    
172     And here is rxvt-unicode:
173    
174     libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
175     libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00002aaaaada2000)
176 root 1.51 libc.so.6 => /lib/libc.so.6 (0x00002aaaaaeb0000)
177     libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab0ee000)
178     /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
179 root 1.42
180     No large bloated libraries (of course, none were linked in statically),
181     except maybe libX11 :)
182    
183     Rendering, Font & Look and Feel Issues
184     I can't get transparency working, what am I doing wrong?
185 root 1.61 First of all, transparency isn't officially supported in rxvt-unicode,
186     so you are mostly on your own. Do not bug the author about it (but you
187     may bug everybody else). Also, if you can't get it working consider it a
188     rite of passage: ... and you failed.
189 root 1.42
190     Here are four ways to get transparency. Do read the manpage and option
191     descriptions for the programs mentioned and rxvt-unicode. Really, do it!
192    
193 root 1.51 1. Use transparent mode:
194 root 1.42
195     Esetroot wallpaper.jpg
196 root 1.51 urxvt -tr -tint red -sh 40
197 root 1.42
198     That works. If you think it doesn't, you lack transparency and tinting
199 root 1.62 support, or you are unable to read. This method requires that the
200     background-setting program sets the _XROOTPMAP_ID or ESETROOT_PMAP_ID
201     property. Compatible programs are Esetroot, hsetroot and feh.
202 root 1.42
203     2. Use a simple pixmap and emulate pseudo-transparency. This enables you
204     to use effects other than tinting and shading: Just shade/tint/whatever
205     your picture with gimp or any other tool:
206    
207 root 1.50 convert wallpaper.jpg -blur 20x20 -modulate 30 background.jpg
208 root 1.51 urxvt -pixmap "background.jpg;:root"
209 root 1.42
210 root 1.66 That works. If you think it doesn't, you lack GDK-PixBuf support, or you
211     are unable to read.
212 root 1.42
213     3. Use an ARGB visual:
214    
215     urxvt -depth 32 -fg grey90 -bg rgba:0000/0000/4444/cccc
216    
217     This requires XFT support, and the support of your X-server. If that
218     doesn't work for you, blame Xorg and Keith Packard. ARGB visuals aren't
219     there yet, no matter what they claim. Rxvt-Unicode contains the
220 root 1.43 necessary bugfixes and workarounds for Xft and Xlib to make it work, but
221     that doesn't mean that your WM has the required kludges in place.
222 root 1.42
223     4. Use xcompmgr and let it do the job:
224    
225     xprop -frame -f _NET_WM_WINDOW_OPACITY 32c \
226     -set _NET_WM_WINDOW_OPACITY 0xc0000000
227    
228     Then click on a window you want to make transparent. Replace 0xc0000000
229     by other values to change the degree of opacity. If it doesn't work and
230     your server crashes, you got to keep the pieces.
231    
232     Why does rxvt-unicode sometimes leave pixel droppings?
233     Most fonts were not designed for terminal use, which means that
234     character size varies a lot. A font that is otherwise fine for terminal
235     use might contain some characters that are simply too wide. Rxvt-unicode
236     will avoid these characters. For characters that are just "a bit" too
237     wide a special "careful" rendering mode is used that redraws adjacent
238     characters.
239    
240     All of this requires that fonts do not lie about character sizes,
241     however: Xft fonts often draw glyphs larger than their acclaimed
242     bounding box, and rxvt-unicode has no way of detecting this (the correct
243     way is to ask for the character bounding box, which unfortunately is
244     wrong in these cases).
245    
246 root 1.43 It's not clear (to me at least), whether this is a bug in Xft, freetype,
247 root 1.42 or the respective font. If you encounter this problem you might try
248     using the "-lsp" option to give the font more height. If that doesn't
249     work, you might be forced to use a different font.
250    
251     All of this is not a problem when using X11 core fonts, as their
252     bounding box data is correct.
253    
254     How can I keep rxvt-unicode from using reverse video so much?
255     First of all, make sure you are running with the right terminal settings
256     ("TERM=rxvt-unicode"), which will get rid of most of these effects. Then
257     make sure you have specified colours for italic and bold, as otherwise
258     rxvt-unicode might use reverse video to simulate the effect:
259    
260     URxvt.colorBD: white
261     URxvt.colorIT: green
262    
263     Some programs assume totally weird colours (red instead of blue), how can I fix that?
264     For some unexplainable reason, some rare programs assume a very weird
265     colour palette when confronted with a terminal with more than the
266     standard 8 colours (rxvt-unicode supports 88). The right fix is, of
267     course, to fix these programs not to assume non-ISO colours without very
268     good reasons.
269    
270     In the meantime, you can either edit your "rxvt-unicode" terminfo
271     definition to only claim 8 colour support or use "TERM=rxvt", which will
272     fix colours but keep you from using other rxvt-unicode features.
273    
274     Can I switch the fonts at runtime?
275     Yes, using an escape sequence. Try something like this, which has the
276     same effect as using the "-fn" switch, and takes effect immediately:
277    
278     printf '\33]50;%s\007' "9x15bold,xft:Kochi Gothic"
279    
280     This is useful if you e.g. work primarily with japanese (and prefer a
281     japanese font), but you have to switch to chinese temporarily, where
282     japanese fonts would only be in your way.
283    
284     You can think of this as a kind of manual ISO-2022 switching.
285    
286     Why do italic characters look as if clipped?
287     Many fonts have difficulties with italic characters and hinting. For
288     example, the otherwise very nicely hinted font "xft:Bitstream Vera Sans
289     Mono" completely fails in its italic face. A workaround might be to
290     enable freetype autohinting, i.e. like this:
291    
292     URxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
293     URxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
294    
295     Can I speed up Xft rendering somehow?
296     Yes, the most obvious way to speed it up is to avoid Xft entirely, as it
297     is simply slow. If you still want Xft fonts you might try to disable
298     antialiasing (by appending ":antialias=false"), which saves lots of
299     memory and also speeds up rendering considerably.
300    
301     Rxvt-unicode doesn't seem to anti-alias its fonts, what is wrong?
302     Rxvt-unicode will use whatever you specify as a font. If it needs to
303     fall back to its default font search list it will prefer X11 core fonts,
304     because they are small and fast, and then use Xft fonts. It has
305     antialiasing disabled for most of them, because the author thinks they
306     look best that way.
307    
308     If you want antialiasing, you have to specify the fonts manually.
309    
310     What's with this bold/blink stuff?
311     If no bold colour is set via "colorBD:", bold will invert text using the
312     standard foreground colour.
313    
314     For the standard background colour, blinking will actually make the text
315 root 1.52 blink when compiled with "--enable-text-blink". Without
316     "--enable-text-blink", the blink attribute will be ignored.
317 root 1.42
318     On ANSI colours, bold/blink attributes are used to set high-intensity
319 sf-exg 1.59 foreground/background colours.
320 root 1.42
321 sf-exg 1.59 color0-7 are the low-intensity colours.
322 root 1.42
323 sf-exg 1.59 color8-15 are the corresponding high-intensity colours.
324 root 1.42
325 sf-exg 1.59 I don't like the screen colours. How do I change them?
326     You can change the screen colours at run-time using ~/.Xdefaults
327 root 1.42 resources (or as long-options).
328    
329     Here are values that are supposed to resemble a VGA screen, including
330     the murky brown that passes for low-intensity yellow:
331    
332     URxvt.color0: #000000
333     URxvt.color1: #A80000
334     URxvt.color2: #00A800
335     URxvt.color3: #A8A800
336     URxvt.color4: #0000A8
337     URxvt.color5: #A800A8
338     URxvt.color6: #00A8A8
339     URxvt.color7: #A8A8A8
340    
341     URxvt.color8: #000054
342     URxvt.color9: #FF0054
343     URxvt.color10: #00FF54
344     URxvt.color11: #FFFF54
345     URxvt.color12: #0000FF
346     URxvt.color13: #FF00FF
347     URxvt.color14: #00FFFF
348     URxvt.color15: #FFFFFF
349    
350 sf-exg 1.59 And here is a more complete set of non-standard colours.
351 root 1.42
352     URxvt.cursorColor: #dc74d1
353     URxvt.pointerColor: #dc74d1
354     URxvt.background: #0e0e0e
355     URxvt.foreground: #4ad5e1
356     URxvt.color0: #000000
357     URxvt.color8: #8b8f93
358     URxvt.color1: #dc74d1
359     URxvt.color9: #dc74d1
360     URxvt.color2: #0eb8c7
361     URxvt.color10: #0eb8c7
362     URxvt.color3: #dfe37e
363     URxvt.color11: #dfe37e
364     URxvt.color5: #9e88f0
365     URxvt.color13: #9e88f0
366     URxvt.color6: #73f7ff
367     URxvt.color14: #73f7ff
368     URxvt.color7: #e1dddd
369     URxvt.color15: #e1dddd
370    
371     They have been described (not by me) as "pretty girly".
372    
373     Why do some characters look so much different than others?
374     See next entry.
375    
376     How does rxvt-unicode choose fonts?
377     Most fonts do not contain the full range of Unicode, which is fine.
378     Chances are that the font you (or the admin/package maintainer of your
379     system/os) have specified does not cover all the characters you want to
380     display.
381    
382     rxvt-unicode makes a best-effort try at finding a replacement font.
383     Often the result is fine, but sometimes the chosen font looks
384     bad/ugly/wrong. Some fonts have totally strange characters that don't
385     resemble the correct glyph at all, and rxvt-unicode lacks the artificial
386     intelligence to detect that a specific glyph is wrong: it has to believe
387     the font that the characters it claims to contain indeed look correct.
388    
389     In that case, select a font of your taste and add it to the font list,
390     e.g.:
391    
392     urxvt -fn basefont,font2,font3...
393    
394     When rxvt-unicode sees a character, it will first look at the base font.
395     If the base font does not contain the character, it will go to the next
396     font, and so on. Specifying your own fonts will also speed up this
397     search and use less resources within rxvt-unicode and the X-server.
398    
399     The only limitation is that none of the fonts may be larger than the
400     base font, as the base font defines the terminal character cell size,
401     which must be the same due to the way terminals work.
402    
403     Why do some chinese characters look so different than others?
404     This is because there is a difference between script and language --
405     rxvt-unicode does not know which language the text that is output is, as
406     it only knows the unicode character codes. If rxvt-unicode first sees a
407     japanese/chinese character, it might choose a japanese font for display.
408     Subsequent japanese characters will use that font. Now, many chinese
409     characters aren't represented in japanese fonts, so when the first
410     non-japanese character comes up, rxvt-unicode will look for a chinese
411     font -- unfortunately at this point, it will still use the japanese font
412     for chinese characters that are also in the japanese font.
413    
414     The workaround is easy: just tag a chinese font at the end of your font
415     list (see the previous question). The key is to view the font list as a
416     preference list: If you expect more japanese, list a japanese font
417     first. If you expect more chinese, put a chinese font first.
418    
419     In the future it might be possible to switch language preferences at
420     runtime (the internal data structure has no problem with using different
421     fonts for the same character at the same time, but no interface for this
422     has been designed yet).
423    
424     Until then, you might get away with switching fonts at runtime (see "Can
425     I switch the fonts at runtime?" later in this document).
426    
427 root 1.50 How can I make mplayer display video correctly?
428     We are working on it, in the meantime, as a workaround, use something
429     like:
430    
431     urxvt -b 600 -geometry 20x1 -e sh -c 'mplayer -wid $WINDOWID file...'
432    
433 root 1.71 Why is the cursor now blinking in emacs/vi/...?
434     This is likely caused by your editor/program's use of the "cvvis"
435     terminfo capability. Emacs uses it by default, as well as some versions
436     of vi and possibly other programs.
437    
438     In emacs, you can switch that off by adding this to your ".emacs" file:
439    
440     (setq visible-cursor nil)
441    
442     For other programs, if they do not have an option, your have to remove
443     the "cvvis" capability from the terminfo description.
444    
445     When urxvt first added the blinking cursor option, it didn't add a
446     "cvvis" capability, which served no purpose before. Version 9.21
447     introduced "cvvis" (and the ability to control blinking independent of
448     cursor shape) for compatibility with other terminals, which
449     traditionally use a blinking cursor for "cvvis". This also reflects the
450     intent of programs such as emacs, who expect "cvvis" to enable a
451     blinking cursor.
452    
453 root 1.42 Keyboard, Mouse & User Interaction
454     The new selection selects pieces that are too big, how can I select single words?
455     If you want to select e.g. alphanumeric words, you can use the following
456     setting:
457    
458     URxvt.selection.pattern-0: ([[:word:]]+)
459    
460     If you click more than twice, the selection will be extended more and
461     more.
462    
463     To get a selection that is very similar to the old code, try this
464     pattern:
465    
466     URxvt.selection.pattern-0: ([^"&'()*,;<=>?@[\\\\]^`{|})]+)
467    
468 root 1.53 Please also note that the *LeftClick Shift-LeftClick* combination also
469 root 1.42 selects words like the old code.
470    
471     I don't like the new selection/popups/hotkeys/perl, how do I change/disable it?
472     You can disable the perl extension completely by setting the
473     perl-ext-common resource to the empty string, which also keeps
474     rxvt-unicode from initialising perl, saving memory.
475    
476     If you only want to disable specific features, you first have to
477     identify which perl extension is responsible. For this, read the section
478     PREPACKAGED EXTENSIONS in the urxvtperl(3) manpage. For example, to
479     disable the selection-popup and option-popup, specify this
480     perl-ext-common resource:
481    
482     URxvt.perl-ext-common: default,-selection-popup,-option-popup
483    
484     This will keep the default extensions, but disable the two popup
485     extensions. Some extensions can also be configured, for example,
486     scrollback search mode is triggered by M-s. You can move it to any other
487     combination either by setting the searchable-scrollback resource:
488    
489     URxvt.searchable-scrollback: CM-s
490    
491     The cursor moves when selecting text in the current input line, how do I switch this off?
492     See next entry.
493    
494     During rlogin/ssh/telnet/etc. sessions, clicking near the cursor outputs strange escape sequences, how do I fix this?
495     These are caused by the "readline" perl extension. Under normal
496     circumstances, it will move your cursor around when you click into the
497     line that contains it. It tries hard not to do this at the wrong moment,
498     but when running a program that doesn't parse cursor movements or in
499     some cases during rlogin sessions, it fails to detect this properly.
500    
501 root 1.43 You can permanently switch this feature off by disabling the "readline"
502 root 1.42 extension:
503    
504     URxvt.perl-ext-common: default,-readline
505    
506 root 1.70 My numeric keypad acts weird and generates differing output?
507     Some Debian GNU/Linux users seem to have this problem, although no
508 root 1.42 specific details were reported so far. It is possible that this is
509 root 1.43 caused by the wrong "TERM" setting, although the details of whether and
510 root 1.42 how this can happen are unknown, as "TERM=rxvt" should offer a
511     compatible keymap. See the answer to the previous question, and please
512     report if that helped.
513    
514     My Compose (Multi_key) key is no longer working.
515     The most common causes for this are that either your locale is not set
516 root 1.69 correctly, or you specified a preeditType that is not supported by your
517 root 1.42 input method. For example, if you specified OverTheSpot and your input
518     method (e.g. the default input method handling Compose keys) does not
519     support this (for instance because it is not visual), then rxvt-unicode
520     will continue without an input method.
521    
522 root 1.69 In this case either do not specify a preeditType or specify more than
523 root 1.42 one pre-edit style, such as OverTheSpot,Root,None.
524    
525 root 1.57 If it still doesn't work, then maybe your input method doesn't support
526     compose sequences - to fall back to the built-in one, make sure you
527     don't specify an input method via "-im" or "XMODIFIERS".
528    
529 root 1.42 I cannot type "Ctrl-Shift-2" to get an ASCII NUL character due to ISO 14755
530     Either try "Ctrl-2" alone (it often is mapped to ASCII NUL even on
531     international keyboards) or simply use ISO 14755 support to your
532     advantage, typing <Ctrl-Shift-0> to get a ASCII NUL. This works for
533     other codes, too, such as "Ctrl-Shift-1-d" to type the default telnet
534     escape character and so on.
535    
536     Mouse cut/paste suddenly no longer works.
537     Make sure that mouse reporting is actually turned off since killing some
538 sf-exg 1.64 editors prematurely may leave it active. I've heard that tcsh may use
539     mouse reporting unless it is otherwise specified. A quick check is to
540     see if cut/paste works when the Alt or Shift keys are pressed.
541 root 1.42
542     What's with the strange Backspace/Delete key behaviour?
543 root 1.43 Assuming that the physical Backspace key corresponds to the Backspace
544 root 1.42 keysym (not likely for Linux ... see the following question) there are
545     two standard values that can be used for Backspace: "^H" and "^?".
546    
547     Historically, either value is correct, but rxvt-unicode adopts the
548 root 1.47 debian policy of using "^?" when unsure, because it's the one and only
549 root 1.42 correct choice :).
550    
551 root 1.60 It is possible to toggle between "^H" and "^?" with the DECBKM private
552     mode:
553 root 1.42
554     # use Backspace = ^H
555     $ stty erase ^H
556 root 1.67 $ printf "\e[?67h"
557 root 1.42
558     # use Backspace = ^?
559     $ stty erase ^?
560 root 1.67 $ printf "\e[?67l"
561 root 1.42
562     This helps satisfy some of the Backspace discrepancies that occur, but
563     if you use Backspace = "^H", make sure that the termcap/terminfo value
564     properly reflects that.
565    
566     The Delete key is a another casualty of the ill-defined Backspace
567     problem. To avoid confusion between the Backspace and Delete keys, the
568     Delete key has been assigned an escape sequence to match the vt100 for
569     Execute ("ESC [ 3 ~") and is in the supplied termcap/terminfo.
570    
571     Some other Backspace problems:
572    
573     some editors use termcap/terminfo, some editors (vim I'm told) expect
574     Backspace = ^H, GNU Emacs (and Emacs-like editors) use ^H for help.
575    
576     Perhaps someday this will all be resolved in a consistent manner.
577    
578     I don't like the key-bindings. How do I change them?
579     There are some compile-time selections available via configure. Unless
580     you have run "configure" with the "--disable-resources" option you can
581     use the `keysym' resource to alter the keystrings associated with
582     keysyms.
583    
584     Here's an example for a URxvt session started using "urxvt -name URxvt"
585    
586 sf-exg 1.64 URxvt.keysym.Prior: \033[5~
587     URxvt.keysym.Next: \033[6~
588     URxvt.keysym.Home: \033[7~
589     URxvt.keysym.End: \033[8~
590     URxvt.keysym.Up: \033[A
591     URxvt.keysym.Down: \033[B
592     URxvt.keysym.Right: \033[C
593     URxvt.keysym.Left: \033[D
594 root 1.42
595     See some more examples in the documentation for the keysym resource.
596    
597     I'm using keyboard model XXX that has extra Prior/Next/Insert keys. How do I make use of them? For example, the Sun Keyboard type 4 has the following map
598     KP_Insert == Insert
599     F22 == Print
600     F27 == Home
601     F29 == Prior
602     F33 == End
603     F35 == Next
604    
605     Rather than have rxvt-unicode try to accommodate all the various
606     possible keyboard mappings, it is better to use `xmodmap' to remap the
607     keys as required for your particular machine.
608    
609     Terminal Configuration
610     Can I see a typical configuration?
611     The default configuration tries to be xterm-like, which I don't like
612     that much, but it's least surprise to regular users.
613    
614     As a rxvt or rxvt-unicode user, you are practically supposed to invest
615     time into customising your terminal. To get you started, here is the
616     author's .Xdefaults entries, with comments on what they do. It's
617     certainly not *typical*, but what's typical...
618    
619     URxvt.cutchars: "()*,<>[]{}|'
620     URxvt.print-pipe: cat >/tmp/xxx
621    
622     These are just for testing stuff.
623    
624     URxvt.imLocale: ja_JP.UTF-8
625     URxvt.preeditType: OnTheSpot,None
626    
627     This tells rxvt-unicode to use a special locale when communicating with
628     the X Input Method, and also tells it to only use the OnTheSpot pre-edit
629     type, which requires the "xim-onthespot" perl extension but rewards me
630     with correct-looking fonts.
631    
632     URxvt.perl-lib: /root/lib/urxvt
633     URxvt.perl-ext-common: default,selection-autotransform,selection-pastebin,xim-onthespot,remote-clipboard
634     URxvt.selection.pattern-0: ( at .*? line \\d+)
635     URxvt.selection.pattern-1: ^(/[^:]+):\
636     URxvt.selection-autotransform.0: s/^([^:[:space:]]+):(\\d+):?$/:e \\Q$1\\E\\x0d:$2\\x0d/
637     URxvt.selection-autotransform.1: s/^ at (.*?) line (\\d+)$/:e \\Q$1\\E\\x0d:$2\\x0d/
638    
639     This is my perl configuration. The first two set the perl library
640     directory and also tells urxvt to use a large number of extensions. I
641     develop for myself mostly, so I actually use most of the extensions I
642     write.
643    
644     The selection stuff mainly makes the selection perl-error-message aware
645 root 1.43 and tells it to convert perl error messages into vi-commands to load the
646 root 1.58 relevant file and go to the error line number.
647 root 1.42
648     URxvt.scrollstyle: plain
649     URxvt.secondaryScroll: true
650    
651     As the documentation says: plain is the preferred scrollbar for the
652 root 1.43 author. The "secondaryScroll" configures urxvt to scroll in full-screen
653     apps, like screen, so lines scrolled out of screen end up in urxvt's
654 root 1.42 scrollback buffer.
655    
656     URxvt.background: #000000
657     URxvt.foreground: gray90
658     URxvt.color7: gray90
659     URxvt.colorBD: #ffffff
660     URxvt.cursorColor: #e0e080
661     URxvt.throughColor: #8080f0
662     URxvt.highlightColor: #f0f0f0
663    
664     Some colours. Not sure which ones are being used or even non-defaults,
665     but these are in my .Xdefaults. Most notably, they set
666     foreground/background to light gray/black, and also make sure that the
667     colour 7 matches the default foreground colour.
668    
669     URxvt.underlineColor: yellow
670    
671     Another colour, makes underline lines look different. Sometimes hurts,
672     but is mostly a nice effect.
673    
674     URxvt.geometry: 154x36
675     URxvt.loginShell: false
676     URxvt.meta: ignore
677     URxvt.utmpInhibit: true
678    
679     Uh, well, should be mostly self-explanatory. By specifying some defaults
680     manually, I can quickly switch them for testing.
681    
682     URxvt.saveLines: 8192
683    
684     A large scrollback buffer is essential. Really.
685    
686     URxvt.mapAlert: true
687    
688     The only case I use it is for my IRC window, which I like to keep
689     iconified till people msg me (which beeps).
690    
691     URxvt.visualBell: true
692    
693     The audible bell is often annoying, especially when in a crowd.
694    
695     URxvt.insecure: true
696    
697     Please don't hack my mutt! Ooops...
698    
699     URxvt.pastableTabs: false
700    
701     I once thought this is a great idea.
702    
703     urxvt.font: 9x15bold,\
704     -misc-fixed-bold-r-normal--15-140-75-75-c-90-iso10646-1,\
705     -misc-fixed-medium-r-normal--15-140-75-75-c-90-iso10646-1, \
706     [codeset=JISX0208]xft:Kochi Gothic, \
707     xft:Bitstream Vera Sans Mono:autohint=true, \
708     xft:Code2000:antialias=false
709     urxvt.boldFont: -xos4-terminus-bold-r-normal--14-140-72-72-c-80-iso8859-15
710     urxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
711     urxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
712    
713     I wrote rxvt-unicode to be able to specify fonts exactly. So don't be
714 root 1.43 overwhelmed. A special note: the "9x15bold" mentioned above is actually
715 root 1.42 the version from XFree-3.3, as XFree-4 replaced it by a totally
716     different font (different glyphs for ";" and many other harmless
717     characters), while the second font is actually the "9x15bold" from
718     XFree4/XOrg. The bold version has less chars than the medium version, so
719 root 1.43 I use it for rare characters, too. When editing sources with vim, I use
720 root 1.42 italic for comments and other stuff, which looks quite good with
721     Bitstream Vera anti-aliased.
722    
723     Terminus is a quite bad font (many very wrong glyphs), but for most of
724     my purposes, it works, and gives a different look, as my normal
725     (Non-bold) font is already bold, and I want to see a difference between
726     bold and normal fonts.
727    
728     Please note that I used the "urxvt" instance name and not the "URxvt"
729 root 1.58 class name. That is because I use different configs for different
730 root 1.42 purposes, for example, my IRC window is started with "-name IRC", and
731     uses these defaults:
732    
733     IRC*title: IRC
734     IRC*geometry: 87x12+535+542
735     IRC*saveLines: 0
736     IRC*mapAlert: true
737     IRC*font: suxuseuro
738     IRC*boldFont: suxuseuro
739     IRC*colorBD: white
740     IRC*keysym.M-C-1: command:\033]710;suxuseuro\007\033]711;suxuseuro\007
741     IRC*keysym.M-C-2: command:\033]710;9x15bold\007\033]711;9x15bold\007
742    
743 root 1.57 "Alt-Ctrl-1" and "Alt-Ctrl-2" switch between two different font sizes.
744 root 1.42 "suxuseuro" allows me to keep an eye (and actually read) stuff while
745     keeping a very small window. If somebody pastes something complicated
746     (e.g. japanese), I temporarily switch to a larger font.
747    
748     The above is all in my ".Xdefaults" (I don't use ".Xresources" nor
749     "xrdb"). I also have some resources in a separate ".Xdefaults-hostname"
750 root 1.60 file for different hosts, for example, on my main desktop, I use:
751 root 1.42
752     URxvt.keysym.C-M-q: command:\033[3;5;5t
753     URxvt.keysym.C-M-y: command:\033[3;5;606t
754     URxvt.keysym.C-M-e: command:\033[3;1605;5t
755     URxvt.keysym.C-M-c: command:\033[3;1605;606t
756     URxvt.keysym.C-M-p: perl:test
757    
758     The first for keysym definitions allow me to quickly bring some windows
759     in the layout I like most. Ion users might start laughing but will stop
760     immediately when I tell them that I use my own Fvwm2 module for much the
761     same effect as Ion provides, and I only very rarely use the above key
762     combinations :->
763    
764     Why doesn't rxvt-unicode read my resources?
765     Well, why, indeed? It does, in a way very similar to other X
766     applications. Most importantly, this means that if you or your OS loads
767     resources into the X display (the right way to do it), rxvt-unicode will
768     ignore any resource files in your home directory. It will only read
769     $HOME/.Xdefaults when no resources are attached to the display.
770    
771     If you have or use an $HOME/.Xresources file, chances are that resources
772     are loaded into your X-server. In this case, you have to re-login after
773     every change (or run xrdb -merge $HOME/.Xresources).
774    
775     Also consider the form resources have to use:
776    
777     URxvt.resource: value
778    
779     If you want to use another form (there are lots of different ways of
780 root 1.43 specifying resources), make sure you understand whether and why it
781     works. If unsure, use the form above.
782 root 1.42
783     When I log-in to another system it tells me about missing terminfo data?
784     The terminal description used by rxvt-unicode is not as widely available
785     as that for xterm, or even rxvt (for which the same problem often
786     arises).
787    
788     The correct solution for this problem is to install the terminfo, this
789 root 1.57 can be done by simply installing rxvt-unicode on the remote system as
790     well (in case you have a nice package manager ready), or you can install
791     the terminfo database manually like this (with ncurses infocmp. works as
792     user and root):
793 root 1.42
794     REMOTE=remotesystem.domain
795 root 1.44 infocmp rxvt-unicode | ssh $REMOTE "mkdir -p .terminfo && cat >/tmp/ti && tic /tmp/ti"
796 root 1.42
797 root 1.44 One some systems you might need to set $TERMINFO to the full path of
798 root 1.70 $HOME/.terminfo for this to work.
799 root 1.44
800 root 1.42 If you cannot or do not want to do this, then you can simply set
801     "TERM=rxvt" or even "TERM=xterm", and live with the small number of
802     problems arising, which includes wrong keymapping, less and different
803     colours and some refresh errors in fullscreen applications. It's a nice
804     quick-and-dirty workaround for rare cases, though.
805    
806     If you always want to do this (and are fine with the consequences) you
807     can either recompile rxvt-unicode with the desired TERM value or use a
808     resource to set it:
809    
810     URxvt.termName: rxvt
811    
812     If you don't plan to use rxvt (quite common...) you could also replace
813     the rxvt terminfo file with the rxvt-unicode one and use "TERM=rxvt".
814    
815 root 1.57 nano fails with "Error opening terminal: rxvt-unicode"
816     This exceptionally confusing and useless error message is printed by
817     nano when it can't find the terminfo database. Nothing is wrong with
818     your terminal, read the previous answer for a solution.
819    
820 root 1.42 "tic" outputs some error when compiling the terminfo entry.
821     Most likely it's the empty definition for "enacs=". Just replace it by
822     "enacs=\E[0@" and try again.
823    
824     "bash"'s readline does not work correctly under urxvt.
825     See next entry.
826    
827     I need a termcap file entry.
828     One reason you might want this is that some distributions or operating
829     systems still compile some programs using the long-obsoleted termcap
830     library (Fedora Core's bash is one example) and rely on a termcap entry
831     for "rxvt-unicode".
832    
833 root 1.43 You could use rxvt's termcap entry with reasonable results in many
834     cases. You can also create a termcap entry by using terminfo's infocmp
835     program like this:
836 root 1.42
837     infocmp -C rxvt-unicode
838    
839 root 1.55 Or you could use the termcap entry in doc/etc/rxvt-unicode.termcap,
840     generated by the command above.
841 root 1.42
842     Why does "ls" no longer have coloured output?
843     The "ls" in the GNU coreutils unfortunately doesn't use terminfo to
844 root 1.43 decide whether a terminal has colour, but uses its own configuration
845 root 1.42 file. Needless to say, "rxvt-unicode" is not in its default file (among
846     with most other terminals supporting colour). Either add:
847    
848     TERM rxvt-unicode
849    
850     to "/etc/DIR_COLORS" or simply add:
851    
852     alias ls='ls --color=auto'
853    
854     to your ".profile" or ".bashrc".
855    
856     Why doesn't vim/emacs etc. use the 88 colour mode?
857     See next entry.
858    
859     Why doesn't vim/emacs etc. make use of italic?
860     See next entry.
861    
862     Why are the secondary screen-related options not working properly?
863     Make sure you are using "TERM=rxvt-unicode". Some pre-packaged
864 root 1.70 distributions break rxvt-unicode by setting "TERM" to "rxvt", which
865     doesn't have these extra features. Unfortunately, some of these
866 root 1.42 furthermore fail to even install the "rxvt-unicode" terminfo file, so
867     you will need to install it on your own (See the question When I log-in
868     to another system it tells me about missing terminfo data? on how to do
869     this).
870    
871     Encoding / Locale / Input Method Issues
872     Rxvt-unicode does not seem to understand the selected encoding?
873     See next entry.
874    
875     Unicode does not seem to work?
876     If you encounter strange problems like typing an accented character but
877     getting two unrelated other characters or similar, or if program output
878     is subtly garbled, then you should check your locale settings.
879    
880     Rxvt-unicode must be started with the same "LC_CTYPE" setting as the
881 root 1.46 programs running in it. Often rxvt-unicode is started in the "C" locale,
882     while the login script running within the rxvt-unicode window changes
883     the locale to something else, e.g. "en_GB.UTF-8". Needless to say, this
884     is not going to work, and is the most common cause for problems.
885 root 1.42
886     The best thing is to fix your startup environment, as you will likely
887     run into other problems. If nothing works you can try this in your
888     .profile.
889    
890 root 1.46 printf '\33]701;%s\007' "$LC_CTYPE" # $LANG or $LC_ALL are worth a try, too
891 root 1.42
892     If this doesn't work, then maybe you use a "LC_CTYPE" specification not
893     supported on your systems. Some systems have a "locale" command which
894     displays this (also, "perl -e0" can be used to check locale settings, as
895     it will complain loudly if it cannot set the locale). If it displays
896     something like:
897    
898     locale: Cannot set LC_CTYPE to default locale: ...
899    
900     Then the locale you specified is not supported on your system.
901    
902     If nothing works and you are sure that everything is set correctly then
903     you will need to remember a little known fact: Some programs just don't
904     support locales :(
905    
906     How does rxvt-unicode determine the encoding to use?
907     See next entry.
908    
909     Is there an option to switch encodings?
910     Unlike some other terminals, rxvt-unicode has no encoding switch, and no
911     specific "utf-8" mode, such as xterm. In fact, it doesn't even know
912     about UTF-8 or any other encodings with respect to terminal I/O.
913    
914     The reasons is that there exists a perfectly fine mechanism for
915     selecting the encoding, doing I/O and (most important) communicating
916     this to all applications so everybody agrees on character properties
917     such as width and code number. This mechanism is the *locale*.
918     Applications not using that info will have problems (for example,
919     "xterm" gets the width of characters wrong as it uses its own,
920     locale-independent table under all locales).
921    
922     Rxvt-unicode uses the "LC_CTYPE" locale category to select encoding. All
923     programs doing the same (that is, most) will automatically agree in the
924     interpretation of characters.
925    
926     Unfortunately, there is no system-independent way to select locales, nor
927     is there a standard on how locale specifiers will look like.
928    
929     On most systems, the content of the "LC_CTYPE" environment variable
930     contains an arbitrary string which corresponds to an already-installed
931     locale. Common names for locales are "en_US.UTF-8", "de_DE.ISO-8859-15",
932     "ja_JP.EUC-JP", i.e. "language_country.encoding", but other forms (i.e.
933     "de" or "german") are also common.
934    
935     Rxvt-unicode ignores all other locale categories, and except for the
936     encoding, ignores country or language-specific settings, i.e.
937     "de_DE.UTF-8" and "ja_JP.UTF-8" are the normally same to rxvt-unicode.
938    
939     If you want to use a specific encoding you have to make sure you start
940     rxvt-unicode with the correct "LC_CTYPE" category.
941    
942     Can I switch locales at runtime?
943     Yes, using an escape sequence. Try something like this, which sets
944     rxvt-unicode's idea of "LC_CTYPE".
945    
946     printf '\33]701;%s\007' ja_JP.SJIS
947    
948     See also the previous answer.
949    
950     Sometimes this capability is rather handy when you want to work in one
951     locale (e.g. "de_DE.UTF-8") but some programs don't support it (e.g.
952     UTF-8). For example, I use this script to start "xjdic", which first
953     switches to a locale supported by xjdic and back later:
954    
955     printf '\33]701;%s\007' ja_JP.SJIS
956     xjdic -js
957     printf '\33]701;%s\007' de_DE.UTF-8
958    
959     You can also use xterm's "luit" program, which usually works fine,
960     except for some locales where character width differs between program-
961     and rxvt-unicode-locales.
962    
963     I have problems getting my input method working.
964     Try a search engine, as this is slightly different for every input
965     method server.
966    
967     Here is a checklist:
968    
969     - Make sure your locale *and* the imLocale are supported on your OS.
970     Try "locale -a" or check the documentation for your OS.
971    
972     - Make sure your locale or imLocale matches a locale supported by your
973     XIM.
974     For example, kinput2 does not support UTF-8 locales, you should use
975     "ja_JP.EUC-JP" or equivalent.
976    
977     - Make sure your XIM server is actually running.
978     - Make sure the "XMODIFIERS" environment variable is set correctly when
979     *starting* rxvt-unicode.
980     When you want to use e.g. kinput2, it must be set to "@im=kinput2".
981 root 1.43 For scim, use "@im=SCIM". You can see what input method servers are
982 root 1.42 running with this command:
983    
984     xprop -root XIM_SERVERS
985    
986     My input method wants <some encoding> but I want UTF-8, what can I do?
987     You can specify separate locales for the input method and the rest of
988     the terminal, using the resource "imlocale":
989    
990     URxvt.imlocale: ja_JP.EUC-JP
991    
992     Now you can start your terminal with "LC_CTYPE=ja_JP.UTF-8" and still
993     use your input method. Please note, however, that, depending on your
994     Xlib version, you may not be able to input characters outside "EUC-JP"
995     in a normal way then, as your input method limits you.
996    
997     Rxvt-unicode crashes when the X Input Method changes or exits.
998     Unfortunately, this is unavoidable, as the XIM protocol is racy by
999     design. Applications can avoid some crashes at the expense of memory
1000     leaks, and Input Methods can avoid some crashes by careful ordering at
1001     exit time. kinput2 (and derived input methods) generally succeeds, while
1002     SCIM (or similar input methods) fails. In the end, however, crashes
1003     cannot be completely avoided even if both sides cooperate.
1004    
1005     So the only workaround is not to kill your Input Method Servers.
1006    
1007     Operating Systems / Package Maintaining
1008     I am maintaining rxvt-unicode for distribution/OS XXX, any recommendation?
1009     You should build one binary with the default options. configure now
1010     enables most useful options, and the trend goes to making them
1011 root 1.43 runtime-switchable, too, so there is usually no drawback to enabling
1012 root 1.42 them, except higher disk and possibly memory usage. The perl interpreter
1013     should be enabled, as important functionality (menus, selection, likely
1014     more in the future) depends on it.
1015    
1016 root 1.58 You should not overwrite the "perl-ext-common" and "perl-ext" resources
1017 root 1.42 system-wide (except maybe with "defaults"). This will result in useful
1018     behaviour. If your distribution aims at low memory, add an empty
1019     "perl-ext-common" resource to the app-defaults file. This will keep the
1020     perl interpreter disabled until the user enables it.
1021    
1022     If you can/want build more binaries, I recommend building a minimal one
1023     with "--disable-everything" (very useful) and a maximal one with
1024     "--enable-everything" (less useful, it will be very big due to a lot of
1025     encodings built-in that increase download times and are rarely used).
1026    
1027     I need to make it setuid/setgid to support utmp/ptys on my OS, is this safe?
1028     It should be, starting with release 7.1. You are encouraged to properly
1029     install urxvt with privileges necessary for your OS now.
1030    
1031     When rxvt-unicode detects that it runs setuid or setgid, it will fork
1032     into a helper process for privileged operations (pty handling on some
1033     systems, utmp/wtmp/lastlog handling on others) and drop privileges
1034     immediately. This is much safer than most other terminals that keep
1035     privileges while running (but is more relevant to urxvt, as it contains
1036     things as perl interpreters, which might be "helpful" to attackers).
1037    
1038     This forking is done as the very first within main(), which is very
1039     early and reduces possible bugs to initialisation code run before
1040     main(), or things like the dynamic loader of your system, which should
1041     result in very little risk.
1042    
1043     I am on FreeBSD and rxvt-unicode does not seem to work at all.
1044     Rxvt-unicode requires the symbol "__STDC_ISO_10646__" to be defined in
1045     your compile environment, or an implementation that implements it,
1046 root 1.43 whether it defines the symbol or not. "__STDC_ISO_10646__" requires that
1047 root 1.42 wchar_t is represented as unicode.
1048    
1049 root 1.43 As you might have guessed, FreeBSD does neither define this symbol nor
1050 root 1.42 does it support it. Instead, it uses its own internal representation of
1051     wchar_t. This is, of course, completely fine with respect to standards.
1052    
1053     However, that means rxvt-unicode only works in "POSIX", "ISO-8859-1" and
1054 root 1.55 "UTF-8" locales under FreeBSD (which all use Unicode as wchar_t).
1055 root 1.42
1056     "__STDC_ISO_10646__" is the only sane way to support multi-language apps
1057     in an OS, as using a locale-dependent (and non-standardized)
1058     representation of wchar_t makes it impossible to convert between wchar_t
1059     (as used by X11 and your applications) and any other encoding without
1060     implementing OS-specific-wrappers for each and every locale. There
1061     simply are no APIs to convert wchar_t into anything except the current
1062     locale encoding.
1063    
1064     Some applications (such as the formidable mlterm) work around this by
1065     carrying their own replacement functions for character set handling with
1066     them, and either implementing OS-dependent hacks or doing multiple
1067     conversions (which is slow and unreliable in case the OS implements
1068     encodings slightly different than the terminal emulator).
1069    
1070     The rxvt-unicode author insists that the right way to fix this is in the
1071     system libraries once and for all, instead of forcing every app to carry
1072     complete replacements for them :)
1073    
1074     How can I use rxvt-unicode under cygwin?
1075     rxvt-unicode should compile and run out of the box on cygwin, using the
1076     X11 libraries that come with cygwin. libW11 emulation is no longer
1077     supported (and makes no sense, either, as it only supported a single
1078     font). I recommend starting the X-server in "-multiwindow" or
1079     "-rootless" mode instead, which will result in similar look&feel as the
1080     old libW11 emulation.
1081    
1082     At the time of this writing, cygwin didn't seem to support any
1083     multi-byte encodings (you might try "LC_CTYPE=C-UTF-8"), so you are
1084     likely limited to 8-bit encodings.
1085    
1086 root 1.49 Character widths are not correct.
1087     urxvt uses the system wcwidth function to know the information about the
1088     width of characters, so on systems with incorrect locale data you will
1089     likely get bad results. Two notorious examples are Solaris 9, where
1090     single-width characters like U+2514 are reported as double-width, and
1091     Darwin 8, where combining chars are reported having width 1.
1092    
1093     The solution is to upgrade your system or switch to a better one. A
1094     possibly working workaround is to use a wcwidth implementation like
1095    
1096     http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
1097