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Revision: 1.64
Committed: Mon May 2 08:25:23 2011 UTC (13 years ago) by sf-exg
Branch: MAIN
CVS Tags: rel-9_14, rel-9_11, rel-9_12
Changes since 1.63: +11 -24 lines
Log Message:
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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     There are three big problems with Gentoo Linux: first of all, most if
10     not all Gentoo systems are completely broken (missing or mismatched
11     header files, broken compiler etc. are just the tip of the iceberg);
12     secondly, the Gentoo maintainer thinks it is a good idea to add broken
13     patches to the code; and lastly, it should be called Gentoo GNU/Linux.
14    
15     For these reasons, it is impossible to support rxvt-unicode on Gentoo.
16     Problems appearing on Gentoo systems will usually simply be ignored
17     unless they can be reproduced on non-Gentoo systems.
18    
19 root 1.42 Does it support tabs, can I have a tabbed rxvt-unicode?
20     Beginning with version 7.3, there is a perl extension that implements a
21     simple tabbed terminal. It is installed by default, so any of these
22     should give you tabs:
23    
24     urxvt -pe tabbed
25    
26     URxvt.perl-ext-common: default,tabbed
27    
28     It will also work fine with tabbing functionality of many window
29     managers or similar tabbing programs, and its embedding-features allow
30     it to be embedded into other programs, as witnessed by doc/rxvt-tabbed
31     or the upcoming "Gtk2::URxvt" perl module, which features a tabbed urxvt
32     (murxvt) terminal as an example embedding application.
33    
34     How do I know which rxvt-unicode version I'm using?
35     The version number is displayed with the usage (-h). Also the escape
36     sequence "ESC [ 8 n" sets the window title to the version number. When
37     using the urxvtc client, the version displayed is that of the daemon.
38    
39     Rxvt-unicode uses gobs of memory, how can I reduce that?
40     Rxvt-unicode tries to obey the rule of not charging you for something
41     you don't use. One thing you should try is to configure out all settings
42     that you don't need, for example, Xft support is a resource hog by
43     design, when used. Compiling it out ensures that no Xft font will be
44     loaded accidentally when rxvt-unicode tries to find a font for your
45     characters.
46    
47     Also, many people (me included) like large windows and even larger
48     scrollback buffers: Without "--enable-unicode3", rxvt-unicode will use 6
49     bytes per screen cell. For a 160x?? window this amounts to almost a
50     kilobyte per line. A scrollback buffer of 10000 lines will then (if
51     full) use 10 Megabytes of memory. With "--enable-unicode3" it gets
52     worse, as rxvt-unicode then uses 8 bytes per screen cell.
53    
54     How can I start urxvtd in a race-free way?
55     Try "urxvtd -f -o", which tells urxvtd to open the display, create the
56     listening socket and then fork.
57    
58 root 1.45 How can I start urxvtd automatically when I run urxvtc?
59 root 1.42 If you want to start urxvtd automatically whenever you run urxvtc and
60     the daemon isn't running yet, use this script:
61    
62     #!/bin/sh
63     urxvtc "$@"
64     if [ $? -eq 2 ]; then
65     urxvtd -q -o -f
66     urxvtc "$@"
67     fi
68    
69     This tries to create a new terminal, and if fails with exit status 2,
70     meaning it couldn't connect to the daemon, it will start the daemon and
71     re-run the command. Subsequent invocations of the script will re-use the
72     existing daemon.
73    
74 sf-exg 1.59 How do I distinguish whether I'm running rxvt-unicode or a regular
75     xterm? I need this to decide about setting colours etc.
76 root 1.42 The original rxvt and rxvt-unicode always export the variable
77     "COLORTERM", so you can check and see if that is set. Note that several
78     programs, JED, slrn, Midnight Commander automatically check this
79 sf-exg 1.59 variable to decide whether or not to use colour.
80 root 1.42
81     How do I set the correct, full IP address for the DISPLAY variable?
82     If you've compiled rxvt-unicode with DISPLAY_IS_IP and have enabled
83     insecure mode then it is possible to use the following shell script
84     snippets to correctly set the display. If your version of rxvt-unicode
85     wasn't also compiled with ESCZ_ANSWER (as assumed in these snippets)
86     then the COLORTERM variable can be used to distinguish rxvt-unicode from
87     a regular xterm.
88    
89     Courtesy of Chuck Blake <cblake@BBN.COM> with the following shell script
90     snippets:
91    
92     # Bourne/Korn/POSIX family of shells:
93     [ ${TERM:-foo} = foo ] && TERM=xterm # assume an xterm if we don't know
94     if [ ${TERM:-foo} = xterm ]; then
95     stty -icanon -echo min 0 time 15 # see if enhanced rxvt or not
96     echo -n '^[Z'
97     read term_id
98     stty icanon echo
99     if [ ""${term_id} = '^[[?1;2C' -a ${DISPLAY:-foo} = foo ]; then
100     echo -n '^[[7n' # query the rxvt we are in for the DISPLAY string
101     read DISPLAY # set it in our local shell
102     fi
103     fi
104    
105     How do I compile the manual pages on my own?
106     You need to have a recent version of perl installed as /usr/bin/perl,
107 root 1.49 one that comes with pod2man, pod2text and pod2xhtml (from Pod::Xhtml).
108 root 1.48 Then go to the doc subdirectory and enter "make alldoc".
109 root 1.42
110     Isn't rxvt-unicode supposed to be small? Don't all those features bloat?
111     I often get asked about this, and I think, no, they didn't cause extra
112     bloat. If you compare a minimal rxvt and a minimal urxvt, you can see
113     that the urxvt binary is larger (due to some encoding tables always
114     being compiled in), but it actually uses less memory (RSS) after
115     startup. Even with "--disable-everything", this comparison is a bit
116     unfair, as many features unique to urxvt (locale, encoding conversion,
117     iso14755 etc.) are already in use in this mode.
118    
119     text data bss drs rss filename
120     98398 1664 24 15695 1824 rxvt --disable-everything
121     188985 9048 66616 18222 1788 urxvt --disable-everything
122    
123     When you "--enable-everything" (which *is* unfair, as this involves xft
124     and full locale/XIM support which are quite bloaty inside libX11 and my
125 root 1.43 libc), the two diverge, but not unreasonably so.
126 root 1.42
127     text data bss drs rss filename
128     163431 2152 24 20123 2060 rxvt --enable-everything
129     1035683 49680 66648 29096 3680 urxvt --enable-everything
130    
131     The very large size of the text section is explained by the east-asian
132     encoding tables, which, if unused, take up disk space but nothing else
133     and can be compiled out unless you rely on X11 core fonts that use those
134     encodings. The BSS size comes from the 64k emergency buffer that my c++
135     compiler allocates (but of course doesn't use unless you are out of
136     memory). Also, using an xft font instead of a core font immediately adds
137     a few megabytes of RSS. Xft indeed is responsible for a lot of RSS even
138     when not used.
139    
140     Of course, due to every character using two or four bytes instead of
141     one, a large scrollback buffer will ultimately make rxvt-unicode use
142     more memory.
143    
144     Compared to e.g. Eterm (5112k), aterm (3132k) and xterm (4680k), this
145     still fares rather well. And compared to some monsters like
146     gnome-terminal (21152k + extra 4204k in separate processes) or konsole
147     (22200k + extra 43180k in daemons that stay around after exit, plus half
148     a minute of startup time, including the hundreds of warnings it spits
149     out), it fares extremely well *g*.
150    
151     Why C++, isn't that unportable/bloated/uncool?
152     Is this a question? :) It comes up very often. The simple answer is: I
153     had to write it, and C++ allowed me to write and maintain it in a
154     fraction of the time and effort (which is a scarce resource for me). Put
155     even shorter: It simply wouldn't exist without C++.
156    
157     My personal stance on this is that C++ is less portable than C, but in
158     the case of rxvt-unicode this hardly matters, as its portability limits
159     are defined by things like X11, pseudo terminals, locale support and
160     unix domain sockets, which are all less portable than C++ itself.
161    
162     Regarding the bloat, see the above question: It's easy to write programs
163 root 1.62 in C that use gobs of memory, and certainly possible to write programs
164     in C++ that don't. C++ also often comes with large libraries, but this
165     is not necessarily the case with GCC. Here is what rxvt links against on
166     my system with a minimal config:
167 root 1.42
168     libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
169     libc.so.6 => /lib/libc.so.6 (0x00002aaaaadde000)
170     libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab01d000)
171     /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
172    
173     And here is rxvt-unicode:
174    
175     libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
176     libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00002aaaaada2000)
177 root 1.51 libc.so.6 => /lib/libc.so.6 (0x00002aaaaaeb0000)
178     libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab0ee000)
179     /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
180 root 1.42
181     No large bloated libraries (of course, none were linked in statically),
182     except maybe libX11 :)
183    
184     Rendering, Font & Look and Feel Issues
185     I can't get transparency working, what am I doing wrong?
186 root 1.61 First of all, transparency isn't officially supported in rxvt-unicode,
187     so you are mostly on your own. Do not bug the author about it (but you
188     may bug everybody else). Also, if you can't get it working consider it a
189     rite of passage: ... and you failed.
190 root 1.42
191     Here are four ways to get transparency. Do read the manpage and option
192     descriptions for the programs mentioned and rxvt-unicode. Really, do it!
193    
194 root 1.51 1. Use transparent mode:
195 root 1.42
196     Esetroot wallpaper.jpg
197 root 1.51 urxvt -tr -tint red -sh 40
198 root 1.42
199     That works. If you think it doesn't, you lack transparency and tinting
200 root 1.62 support, or you are unable to read. This method requires that the
201     background-setting program sets the _XROOTPMAP_ID or ESETROOT_PMAP_ID
202     property. Compatible programs are Esetroot, hsetroot and feh.
203 root 1.42
204     2. Use a simple pixmap and emulate pseudo-transparency. This enables you
205     to use effects other than tinting and shading: Just shade/tint/whatever
206     your picture with gimp or any other tool:
207    
208 root 1.50 convert wallpaper.jpg -blur 20x20 -modulate 30 background.jpg
209 root 1.51 urxvt -pixmap "background.jpg;:root"
210 root 1.42
211 root 1.60 That works. If you think it doesn't, you lack libAfterImage or
212     GDK-PixBuf support, or you are unable to read.
213 root 1.42
214     3. Use an ARGB visual:
215    
216     urxvt -depth 32 -fg grey90 -bg rgba:0000/0000/4444/cccc
217    
218     This requires XFT support, and the support of your X-server. If that
219     doesn't work for you, blame Xorg and Keith Packard. ARGB visuals aren't
220     there yet, no matter what they claim. Rxvt-Unicode contains the
221 root 1.43 necessary bugfixes and workarounds for Xft and Xlib to make it work, but
222     that doesn't mean that your WM has the required kludges in place.
223 root 1.42
224     4. Use xcompmgr and let it do the job:
225    
226     xprop -frame -f _NET_WM_WINDOW_OPACITY 32c \
227     -set _NET_WM_WINDOW_OPACITY 0xc0000000
228    
229     Then click on a window you want to make transparent. Replace 0xc0000000
230     by other values to change the degree of opacity. If it doesn't work and
231     your server crashes, you got to keep the pieces.
232    
233     Why does rxvt-unicode sometimes leave pixel droppings?
234     Most fonts were not designed for terminal use, which means that
235     character size varies a lot. A font that is otherwise fine for terminal
236     use might contain some characters that are simply too wide. Rxvt-unicode
237     will avoid these characters. For characters that are just "a bit" too
238     wide a special "careful" rendering mode is used that redraws adjacent
239     characters.
240    
241     All of this requires that fonts do not lie about character sizes,
242     however: Xft fonts often draw glyphs larger than their acclaimed
243     bounding box, and rxvt-unicode has no way of detecting this (the correct
244     way is to ask for the character bounding box, which unfortunately is
245     wrong in these cases).
246    
247 root 1.43 It's not clear (to me at least), whether this is a bug in Xft, freetype,
248 root 1.42 or the respective font. If you encounter this problem you might try
249     using the "-lsp" option to give the font more height. If that doesn't
250     work, you might be forced to use a different font.
251    
252     All of this is not a problem when using X11 core fonts, as their
253     bounding box data is correct.
254    
255     How can I keep rxvt-unicode from using reverse video so much?
256     First of all, make sure you are running with the right terminal settings
257     ("TERM=rxvt-unicode"), which will get rid of most of these effects. Then
258     make sure you have specified colours for italic and bold, as otherwise
259     rxvt-unicode might use reverse video to simulate the effect:
260    
261     URxvt.colorBD: white
262     URxvt.colorIT: green
263    
264     Some programs assume totally weird colours (red instead of blue), how can I fix that?
265     For some unexplainable reason, some rare programs assume a very weird
266     colour palette when confronted with a terminal with more than the
267     standard 8 colours (rxvt-unicode supports 88). The right fix is, of
268     course, to fix these programs not to assume non-ISO colours without very
269     good reasons.
270    
271     In the meantime, you can either edit your "rxvt-unicode" terminfo
272     definition to only claim 8 colour support or use "TERM=rxvt", which will
273     fix colours but keep you from using other rxvt-unicode features.
274    
275     Can I switch the fonts at runtime?
276     Yes, using an escape sequence. Try something like this, which has the
277     same effect as using the "-fn" switch, and takes effect immediately:
278    
279     printf '\33]50;%s\007' "9x15bold,xft:Kochi Gothic"
280    
281     This is useful if you e.g. work primarily with japanese (and prefer a
282     japanese font), but you have to switch to chinese temporarily, where
283     japanese fonts would only be in your way.
284    
285     You can think of this as a kind of manual ISO-2022 switching.
286    
287     Why do italic characters look as if clipped?
288     Many fonts have difficulties with italic characters and hinting. For
289     example, the otherwise very nicely hinted font "xft:Bitstream Vera Sans
290     Mono" completely fails in its italic face. A workaround might be to
291     enable freetype autohinting, i.e. like this:
292    
293     URxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
294     URxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
295    
296     Can I speed up Xft rendering somehow?
297     Yes, the most obvious way to speed it up is to avoid Xft entirely, as it
298     is simply slow. If you still want Xft fonts you might try to disable
299     antialiasing (by appending ":antialias=false"), which saves lots of
300     memory and also speeds up rendering considerably.
301    
302     Rxvt-unicode doesn't seem to anti-alias its fonts, what is wrong?
303     Rxvt-unicode will use whatever you specify as a font. If it needs to
304     fall back to its default font search list it will prefer X11 core fonts,
305     because they are small and fast, and then use Xft fonts. It has
306     antialiasing disabled for most of them, because the author thinks they
307     look best that way.
308    
309     If you want antialiasing, you have to specify the fonts manually.
310    
311     What's with this bold/blink stuff?
312     If no bold colour is set via "colorBD:", bold will invert text using the
313     standard foreground colour.
314    
315     For the standard background colour, blinking will actually make the text
316 root 1.52 blink when compiled with "--enable-text-blink". Without
317     "--enable-text-blink", the blink attribute will be ignored.
318 root 1.42
319     On ANSI colours, bold/blink attributes are used to set high-intensity
320 sf-exg 1.59 foreground/background colours.
321 root 1.42
322 sf-exg 1.59 color0-7 are the low-intensity colours.
323 root 1.42
324 sf-exg 1.59 color8-15 are the corresponding high-intensity colours.
325 root 1.42
326 sf-exg 1.59 I don't like the screen colours. How do I change them?
327     You can change the screen colours at run-time using ~/.Xdefaults
328 root 1.42 resources (or as long-options).
329    
330     Here are values that are supposed to resemble a VGA screen, including
331     the murky brown that passes for low-intensity yellow:
332    
333     URxvt.color0: #000000
334     URxvt.color1: #A80000
335     URxvt.color2: #00A800
336     URxvt.color3: #A8A800
337     URxvt.color4: #0000A8
338     URxvt.color5: #A800A8
339     URxvt.color6: #00A8A8
340     URxvt.color7: #A8A8A8
341    
342     URxvt.color8: #000054
343     URxvt.color9: #FF0054
344     URxvt.color10: #00FF54
345     URxvt.color11: #FFFF54
346     URxvt.color12: #0000FF
347     URxvt.color13: #FF00FF
348     URxvt.color14: #00FFFF
349     URxvt.color15: #FFFFFF
350    
351 sf-exg 1.59 And here is a more complete set of non-standard colours.
352 root 1.42
353     URxvt.cursorColor: #dc74d1
354     URxvt.pointerColor: #dc74d1
355     URxvt.background: #0e0e0e
356     URxvt.foreground: #4ad5e1
357     URxvt.color0: #000000
358     URxvt.color8: #8b8f93
359     URxvt.color1: #dc74d1
360     URxvt.color9: #dc74d1
361     URxvt.color2: #0eb8c7
362     URxvt.color10: #0eb8c7
363     URxvt.color3: #dfe37e
364     URxvt.color11: #dfe37e
365     URxvt.color5: #9e88f0
366     URxvt.color13: #9e88f0
367     URxvt.color6: #73f7ff
368     URxvt.color14: #73f7ff
369     URxvt.color7: #e1dddd
370     URxvt.color15: #e1dddd
371    
372     They have been described (not by me) as "pretty girly".
373    
374     Why do some characters look so much different than others?
375     See next entry.
376    
377     How does rxvt-unicode choose fonts?
378     Most fonts do not contain the full range of Unicode, which is fine.
379     Chances are that the font you (or the admin/package maintainer of your
380     system/os) have specified does not cover all the characters you want to
381     display.
382    
383     rxvt-unicode makes a best-effort try at finding a replacement font.
384     Often the result is fine, but sometimes the chosen font looks
385     bad/ugly/wrong. Some fonts have totally strange characters that don't
386     resemble the correct glyph at all, and rxvt-unicode lacks the artificial
387     intelligence to detect that a specific glyph is wrong: it has to believe
388     the font that the characters it claims to contain indeed look correct.
389    
390     In that case, select a font of your taste and add it to the font list,
391     e.g.:
392    
393     urxvt -fn basefont,font2,font3...
394    
395     When rxvt-unicode sees a character, it will first look at the base font.
396     If the base font does not contain the character, it will go to the next
397     font, and so on. Specifying your own fonts will also speed up this
398     search and use less resources within rxvt-unicode and the X-server.
399    
400     The only limitation is that none of the fonts may be larger than the
401     base font, as the base font defines the terminal character cell size,
402     which must be the same due to the way terminals work.
403    
404     Why do some chinese characters look so different than others?
405     This is because there is a difference between script and language --
406     rxvt-unicode does not know which language the text that is output is, as
407     it only knows the unicode character codes. If rxvt-unicode first sees a
408     japanese/chinese character, it might choose a japanese font for display.
409     Subsequent japanese characters will use that font. Now, many chinese
410     characters aren't represented in japanese fonts, so when the first
411     non-japanese character comes up, rxvt-unicode will look for a chinese
412     font -- unfortunately at this point, it will still use the japanese font
413     for chinese characters that are also in the japanese font.
414    
415     The workaround is easy: just tag a chinese font at the end of your font
416     list (see the previous question). The key is to view the font list as a
417     preference list: If you expect more japanese, list a japanese font
418     first. If you expect more chinese, put a chinese font first.
419    
420     In the future it might be possible to switch language preferences at
421     runtime (the internal data structure has no problem with using different
422     fonts for the same character at the same time, but no interface for this
423     has been designed yet).
424    
425     Until then, you might get away with switching fonts at runtime (see "Can
426     I switch the fonts at runtime?" later in this document).
427    
428 root 1.50 How can I make mplayer display video correctly?
429     We are working on it, in the meantime, as a workaround, use something
430     like:
431    
432     urxvt -b 600 -geometry 20x1 -e sh -c 'mplayer -wid $WINDOWID file...'
433    
434 root 1.42 Keyboard, Mouse & User Interaction
435     The new selection selects pieces that are too big, how can I select single words?
436     If you want to select e.g. alphanumeric words, you can use the following
437     setting:
438    
439     URxvt.selection.pattern-0: ([[:word:]]+)
440    
441     If you click more than twice, the selection will be extended more and
442     more.
443    
444     To get a selection that is very similar to the old code, try this
445     pattern:
446    
447     URxvt.selection.pattern-0: ([^"&'()*,;<=>?@[\\\\]^`{|})]+)
448    
449 root 1.53 Please also note that the *LeftClick Shift-LeftClick* combination also
450 root 1.42 selects words like the old code.
451    
452     I don't like the new selection/popups/hotkeys/perl, how do I change/disable it?
453     You can disable the perl extension completely by setting the
454     perl-ext-common resource to the empty string, which also keeps
455     rxvt-unicode from initialising perl, saving memory.
456    
457     If you only want to disable specific features, you first have to
458     identify which perl extension is responsible. For this, read the section
459     PREPACKAGED EXTENSIONS in the urxvtperl(3) manpage. For example, to
460     disable the selection-popup and option-popup, specify this
461     perl-ext-common resource:
462    
463     URxvt.perl-ext-common: default,-selection-popup,-option-popup
464    
465     This will keep the default extensions, but disable the two popup
466     extensions. Some extensions can also be configured, for example,
467     scrollback search mode is triggered by M-s. You can move it to any other
468     combination either by setting the searchable-scrollback resource:
469    
470     URxvt.searchable-scrollback: CM-s
471    
472     The cursor moves when selecting text in the current input line, how do I switch this off?
473     See next entry.
474    
475     During rlogin/ssh/telnet/etc. sessions, clicking near the cursor outputs strange escape sequences, how do I fix this?
476     These are caused by the "readline" perl extension. Under normal
477     circumstances, it will move your cursor around when you click into the
478     line that contains it. It tries hard not to do this at the wrong moment,
479     but when running a program that doesn't parse cursor movements or in
480     some cases during rlogin sessions, it fails to detect this properly.
481    
482 root 1.43 You can permanently switch this feature off by disabling the "readline"
483 root 1.42 extension:
484    
485     URxvt.perl-ext-common: default,-readline
486    
487     My numerical keypad acts weird and generates differing output?
488     Some Debian GNUL/Linux users seem to have this problem, although no
489     specific details were reported so far. It is possible that this is
490 root 1.43 caused by the wrong "TERM" setting, although the details of whether and
491 root 1.42 how this can happen are unknown, as "TERM=rxvt" should offer a
492     compatible keymap. See the answer to the previous question, and please
493     report if that helped.
494    
495     My Compose (Multi_key) key is no longer working.
496     The most common causes for this are that either your locale is not set
497     correctly, or you specified a preeditStyle that is not supported by your
498     input method. For example, if you specified OverTheSpot and your input
499     method (e.g. the default input method handling Compose keys) does not
500     support this (for instance because it is not visual), then rxvt-unicode
501     will continue without an input method.
502    
503     In this case either do not specify a preeditStyle or specify more than
504     one pre-edit style, such as OverTheSpot,Root,None.
505    
506 root 1.57 If it still doesn't work, then maybe your input method doesn't support
507     compose sequences - to fall back to the built-in one, make sure you
508     don't specify an input method via "-im" or "XMODIFIERS".
509    
510 root 1.42 I cannot type "Ctrl-Shift-2" to get an ASCII NUL character due to ISO 14755
511     Either try "Ctrl-2" alone (it often is mapped to ASCII NUL even on
512     international keyboards) or simply use ISO 14755 support to your
513     advantage, typing <Ctrl-Shift-0> to get a ASCII NUL. This works for
514     other codes, too, such as "Ctrl-Shift-1-d" to type the default telnet
515     escape character and so on.
516    
517     Mouse cut/paste suddenly no longer works.
518     Make sure that mouse reporting is actually turned off since killing some
519 sf-exg 1.64 editors prematurely may leave it active. I've heard that tcsh may use
520     mouse reporting unless it is otherwise specified. A quick check is to
521     see if cut/paste works when the Alt or Shift keys are pressed.
522 root 1.42
523     What's with the strange Backspace/Delete key behaviour?
524 root 1.43 Assuming that the physical Backspace key corresponds to the Backspace
525 root 1.42 keysym (not likely for Linux ... see the following question) there are
526     two standard values that can be used for Backspace: "^H" and "^?".
527    
528     Historically, either value is correct, but rxvt-unicode adopts the
529 root 1.47 debian policy of using "^?" when unsure, because it's the one and only
530 root 1.42 correct choice :).
531    
532 root 1.60 It is possible to toggle between "^H" and "^?" with the DECBKM private
533     mode:
534 root 1.42
535     # use Backspace = ^H
536     $ stty erase ^H
537 root 1.60 $ echo -n "^[[?67h"
538 root 1.42
539     # use Backspace = ^?
540     $ stty erase ^?
541 root 1.60 $ echo -n "^[[?67l"
542 root 1.42
543     This helps satisfy some of the Backspace discrepancies that occur, but
544     if you use Backspace = "^H", make sure that the termcap/terminfo value
545     properly reflects that.
546    
547     The Delete key is a another casualty of the ill-defined Backspace
548     problem. To avoid confusion between the Backspace and Delete keys, the
549     Delete key has been assigned an escape sequence to match the vt100 for
550     Execute ("ESC [ 3 ~") and is in the supplied termcap/terminfo.
551    
552     Some other Backspace problems:
553    
554     some editors use termcap/terminfo, some editors (vim I'm told) expect
555     Backspace = ^H, GNU Emacs (and Emacs-like editors) use ^H for help.
556    
557     Perhaps someday this will all be resolved in a consistent manner.
558    
559     I don't like the key-bindings. How do I change them?
560     There are some compile-time selections available via configure. Unless
561     you have run "configure" with the "--disable-resources" option you can
562     use the `keysym' resource to alter the keystrings associated with
563     keysyms.
564    
565     Here's an example for a URxvt session started using "urxvt -name URxvt"
566    
567 sf-exg 1.64 URxvt.keysym.Prior: \033[5~
568     URxvt.keysym.Next: \033[6~
569     URxvt.keysym.Home: \033[7~
570     URxvt.keysym.End: \033[8~
571     URxvt.keysym.Up: \033[A
572     URxvt.keysym.Down: \033[B
573     URxvt.keysym.Right: \033[C
574     URxvt.keysym.Left: \033[D
575 root 1.42
576     See some more examples in the documentation for the keysym resource.
577    
578     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
579     KP_Insert == Insert
580     F22 == Print
581     F27 == Home
582     F29 == Prior
583     F33 == End
584     F35 == Next
585    
586     Rather than have rxvt-unicode try to accommodate all the various
587     possible keyboard mappings, it is better to use `xmodmap' to remap the
588     keys as required for your particular machine.
589    
590     Terminal Configuration
591     Can I see a typical configuration?
592     The default configuration tries to be xterm-like, which I don't like
593     that much, but it's least surprise to regular users.
594    
595     As a rxvt or rxvt-unicode user, you are practically supposed to invest
596     time into customising your terminal. To get you started, here is the
597     author's .Xdefaults entries, with comments on what they do. It's
598     certainly not *typical*, but what's typical...
599    
600     URxvt.cutchars: "()*,<>[]{}|'
601     URxvt.print-pipe: cat >/tmp/xxx
602    
603     These are just for testing stuff.
604    
605     URxvt.imLocale: ja_JP.UTF-8
606     URxvt.preeditType: OnTheSpot,None
607    
608     This tells rxvt-unicode to use a special locale when communicating with
609     the X Input Method, and also tells it to only use the OnTheSpot pre-edit
610     type, which requires the "xim-onthespot" perl extension but rewards me
611     with correct-looking fonts.
612    
613     URxvt.perl-lib: /root/lib/urxvt
614     URxvt.perl-ext-common: default,selection-autotransform,selection-pastebin,xim-onthespot,remote-clipboard
615     URxvt.selection.pattern-0: ( at .*? line \\d+)
616     URxvt.selection.pattern-1: ^(/[^:]+):\
617     URxvt.selection-autotransform.0: s/^([^:[:space:]]+):(\\d+):?$/:e \\Q$1\\E\\x0d:$2\\x0d/
618     URxvt.selection-autotransform.1: s/^ at (.*?) line (\\d+)$/:e \\Q$1\\E\\x0d:$2\\x0d/
619    
620     This is my perl configuration. The first two set the perl library
621     directory and also tells urxvt to use a large number of extensions. I
622     develop for myself mostly, so I actually use most of the extensions I
623     write.
624    
625     The selection stuff mainly makes the selection perl-error-message aware
626 root 1.43 and tells it to convert perl error messages into vi-commands to load the
627 root 1.58 relevant file and go to the error line number.
628 root 1.42
629     URxvt.scrollstyle: plain
630     URxvt.secondaryScroll: true
631    
632     As the documentation says: plain is the preferred scrollbar for the
633 root 1.43 author. The "secondaryScroll" configures urxvt to scroll in full-screen
634     apps, like screen, so lines scrolled out of screen end up in urxvt's
635 root 1.42 scrollback buffer.
636    
637     URxvt.background: #000000
638     URxvt.foreground: gray90
639     URxvt.color7: gray90
640     URxvt.colorBD: #ffffff
641     URxvt.cursorColor: #e0e080
642     URxvt.throughColor: #8080f0
643     URxvt.highlightColor: #f0f0f0
644    
645     Some colours. Not sure which ones are being used or even non-defaults,
646     but these are in my .Xdefaults. Most notably, they set
647     foreground/background to light gray/black, and also make sure that the
648     colour 7 matches the default foreground colour.
649    
650     URxvt.underlineColor: yellow
651    
652     Another colour, makes underline lines look different. Sometimes hurts,
653     but is mostly a nice effect.
654    
655     URxvt.geometry: 154x36
656     URxvt.loginShell: false
657     URxvt.meta: ignore
658     URxvt.utmpInhibit: true
659    
660     Uh, well, should be mostly self-explanatory. By specifying some defaults
661     manually, I can quickly switch them for testing.
662    
663     URxvt.saveLines: 8192
664    
665     A large scrollback buffer is essential. Really.
666    
667     URxvt.mapAlert: true
668    
669     The only case I use it is for my IRC window, which I like to keep
670     iconified till people msg me (which beeps).
671    
672     URxvt.visualBell: true
673    
674     The audible bell is often annoying, especially when in a crowd.
675    
676     URxvt.insecure: true
677    
678     Please don't hack my mutt! Ooops...
679    
680     URxvt.pastableTabs: false
681    
682     I once thought this is a great idea.
683    
684     urxvt.font: 9x15bold,\
685     -misc-fixed-bold-r-normal--15-140-75-75-c-90-iso10646-1,\
686     -misc-fixed-medium-r-normal--15-140-75-75-c-90-iso10646-1, \
687     [codeset=JISX0208]xft:Kochi Gothic, \
688     xft:Bitstream Vera Sans Mono:autohint=true, \
689     xft:Code2000:antialias=false
690     urxvt.boldFont: -xos4-terminus-bold-r-normal--14-140-72-72-c-80-iso8859-15
691     urxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
692     urxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
693    
694     I wrote rxvt-unicode to be able to specify fonts exactly. So don't be
695 root 1.43 overwhelmed. A special note: the "9x15bold" mentioned above is actually
696 root 1.42 the version from XFree-3.3, as XFree-4 replaced it by a totally
697     different font (different glyphs for ";" and many other harmless
698     characters), while the second font is actually the "9x15bold" from
699     XFree4/XOrg. The bold version has less chars than the medium version, so
700 root 1.43 I use it for rare characters, too. When editing sources with vim, I use
701 root 1.42 italic for comments and other stuff, which looks quite good with
702     Bitstream Vera anti-aliased.
703    
704     Terminus is a quite bad font (many very wrong glyphs), but for most of
705     my purposes, it works, and gives a different look, as my normal
706     (Non-bold) font is already bold, and I want to see a difference between
707     bold and normal fonts.
708    
709     Please note that I used the "urxvt" instance name and not the "URxvt"
710 root 1.58 class name. That is because I use different configs for different
711 root 1.42 purposes, for example, my IRC window is started with "-name IRC", and
712     uses these defaults:
713    
714     IRC*title: IRC
715     IRC*geometry: 87x12+535+542
716     IRC*saveLines: 0
717     IRC*mapAlert: true
718     IRC*font: suxuseuro
719     IRC*boldFont: suxuseuro
720     IRC*colorBD: white
721     IRC*keysym.M-C-1: command:\033]710;suxuseuro\007\033]711;suxuseuro\007
722     IRC*keysym.M-C-2: command:\033]710;9x15bold\007\033]711;9x15bold\007
723    
724 root 1.57 "Alt-Ctrl-1" and "Alt-Ctrl-2" switch between two different font sizes.
725 root 1.42 "suxuseuro" allows me to keep an eye (and actually read) stuff while
726     keeping a very small window. If somebody pastes something complicated
727     (e.g. japanese), I temporarily switch to a larger font.
728    
729     The above is all in my ".Xdefaults" (I don't use ".Xresources" nor
730     "xrdb"). I also have some resources in a separate ".Xdefaults-hostname"
731 root 1.60 file for different hosts, for example, on my main desktop, I use:
732 root 1.42
733     URxvt.keysym.C-M-q: command:\033[3;5;5t
734     URxvt.keysym.C-M-y: command:\033[3;5;606t
735     URxvt.keysym.C-M-e: command:\033[3;1605;5t
736     URxvt.keysym.C-M-c: command:\033[3;1605;606t
737     URxvt.keysym.C-M-p: perl:test
738    
739     The first for keysym definitions allow me to quickly bring some windows
740     in the layout I like most. Ion users might start laughing but will stop
741     immediately when I tell them that I use my own Fvwm2 module for much the
742     same effect as Ion provides, and I only very rarely use the above key
743     combinations :->
744    
745     Why doesn't rxvt-unicode read my resources?
746     Well, why, indeed? It does, in a way very similar to other X
747     applications. Most importantly, this means that if you or your OS loads
748     resources into the X display (the right way to do it), rxvt-unicode will
749     ignore any resource files in your home directory. It will only read
750     $HOME/.Xdefaults when no resources are attached to the display.
751    
752     If you have or use an $HOME/.Xresources file, chances are that resources
753     are loaded into your X-server. In this case, you have to re-login after
754     every change (or run xrdb -merge $HOME/.Xresources).
755    
756     Also consider the form resources have to use:
757    
758     URxvt.resource: value
759    
760     If you want to use another form (there are lots of different ways of
761 root 1.43 specifying resources), make sure you understand whether and why it
762     works. If unsure, use the form above.
763 root 1.42
764     When I log-in to another system it tells me about missing terminfo data?
765     The terminal description used by rxvt-unicode is not as widely available
766     as that for xterm, or even rxvt (for which the same problem often
767     arises).
768    
769     The correct solution for this problem is to install the terminfo, this
770 root 1.57 can be done by simply installing rxvt-unicode on the remote system as
771     well (in case you have a nice package manager ready), or you can install
772     the terminfo database manually like this (with ncurses infocmp. works as
773     user and root):
774 root 1.42
775     REMOTE=remotesystem.domain
776 root 1.44 infocmp rxvt-unicode | ssh $REMOTE "mkdir -p .terminfo && cat >/tmp/ti && tic /tmp/ti"
777 root 1.42
778 root 1.44 One some systems you might need to set $TERMINFO to the full path of
779     $HOME/.terminfo for this to work.
780    
781 root 1.42 If you cannot or do not want to do this, then you can simply set
782     "TERM=rxvt" or even "TERM=xterm", and live with the small number of
783     problems arising, which includes wrong keymapping, less and different
784     colours and some refresh errors in fullscreen applications. It's a nice
785     quick-and-dirty workaround for rare cases, though.
786    
787     If you always want to do this (and are fine with the consequences) you
788     can either recompile rxvt-unicode with the desired TERM value or use a
789     resource to set it:
790    
791     URxvt.termName: rxvt
792    
793     If you don't plan to use rxvt (quite common...) you could also replace
794     the rxvt terminfo file with the rxvt-unicode one and use "TERM=rxvt".
795    
796 root 1.57 nano fails with "Error opening terminal: rxvt-unicode"
797     This exceptionally confusing and useless error message is printed by
798     nano when it can't find the terminfo database. Nothing is wrong with
799     your terminal, read the previous answer for a solution.
800    
801 root 1.42 "tic" outputs some error when compiling the terminfo entry.
802     Most likely it's the empty definition for "enacs=". Just replace it by
803     "enacs=\E[0@" and try again.
804    
805     "bash"'s readline does not work correctly under urxvt.
806     See next entry.
807    
808     I need a termcap file entry.
809     One reason you might want this is that some distributions or operating
810     systems still compile some programs using the long-obsoleted termcap
811     library (Fedora Core's bash is one example) and rely on a termcap entry
812     for "rxvt-unicode".
813    
814 root 1.43 You could use rxvt's termcap entry with reasonable results in many
815     cases. You can also create a termcap entry by using terminfo's infocmp
816     program like this:
817 root 1.42
818     infocmp -C rxvt-unicode
819    
820 root 1.55 Or you could use the termcap entry in doc/etc/rxvt-unicode.termcap,
821     generated by the command above.
822 root 1.42
823     Why does "ls" no longer have coloured output?
824     The "ls" in the GNU coreutils unfortunately doesn't use terminfo to
825 root 1.43 decide whether a terminal has colour, but uses its own configuration
826 root 1.42 file. Needless to say, "rxvt-unicode" is not in its default file (among
827     with most other terminals supporting colour). Either add:
828    
829     TERM rxvt-unicode
830    
831     to "/etc/DIR_COLORS" or simply add:
832    
833     alias ls='ls --color=auto'
834    
835     to your ".profile" or ".bashrc".
836    
837     Why doesn't vim/emacs etc. use the 88 colour mode?
838     See next entry.
839    
840     Why doesn't vim/emacs etc. make use of italic?
841     See next entry.
842    
843     Why are the secondary screen-related options not working properly?
844     Make sure you are using "TERM=rxvt-unicode". Some pre-packaged
845     distributions (most notably Debian GNU/Linux) break rxvt-unicode by
846     setting "TERM" to "rxvt", which doesn't have these extra features.
847     Unfortunately, some of these (most notably, again, Debian GNU/Linux)
848     furthermore fail to even install the "rxvt-unicode" terminfo file, so
849     you will need to install it on your own (See the question When I log-in
850     to another system it tells me about missing terminfo data? on how to do
851     this).
852    
853     Encoding / Locale / Input Method Issues
854     Rxvt-unicode does not seem to understand the selected encoding?
855     See next entry.
856    
857     Unicode does not seem to work?
858     If you encounter strange problems like typing an accented character but
859     getting two unrelated other characters or similar, or if program output
860     is subtly garbled, then you should check your locale settings.
861    
862     Rxvt-unicode must be started with the same "LC_CTYPE" setting as the
863 root 1.46 programs running in it. Often rxvt-unicode is started in the "C" locale,
864     while the login script running within the rxvt-unicode window changes
865     the locale to something else, e.g. "en_GB.UTF-8". Needless to say, this
866     is not going to work, and is the most common cause for problems.
867 root 1.42
868     The best thing is to fix your startup environment, as you will likely
869     run into other problems. If nothing works you can try this in your
870     .profile.
871    
872 root 1.46 printf '\33]701;%s\007' "$LC_CTYPE" # $LANG or $LC_ALL are worth a try, too
873 root 1.42
874     If this doesn't work, then maybe you use a "LC_CTYPE" specification not
875     supported on your systems. Some systems have a "locale" command which
876     displays this (also, "perl -e0" can be used to check locale settings, as
877     it will complain loudly if it cannot set the locale). If it displays
878     something like:
879    
880     locale: Cannot set LC_CTYPE to default locale: ...
881    
882     Then the locale you specified is not supported on your system.
883    
884     If nothing works and you are sure that everything is set correctly then
885     you will need to remember a little known fact: Some programs just don't
886     support locales :(
887    
888     How does rxvt-unicode determine the encoding to use?
889     See next entry.
890    
891     Is there an option to switch encodings?
892     Unlike some other terminals, rxvt-unicode has no encoding switch, and no
893     specific "utf-8" mode, such as xterm. In fact, it doesn't even know
894     about UTF-8 or any other encodings with respect to terminal I/O.
895    
896     The reasons is that there exists a perfectly fine mechanism for
897     selecting the encoding, doing I/O and (most important) communicating
898     this to all applications so everybody agrees on character properties
899     such as width and code number. This mechanism is the *locale*.
900     Applications not using that info will have problems (for example,
901     "xterm" gets the width of characters wrong as it uses its own,
902     locale-independent table under all locales).
903    
904     Rxvt-unicode uses the "LC_CTYPE" locale category to select encoding. All
905     programs doing the same (that is, most) will automatically agree in the
906     interpretation of characters.
907    
908     Unfortunately, there is no system-independent way to select locales, nor
909     is there a standard on how locale specifiers will look like.
910    
911     On most systems, the content of the "LC_CTYPE" environment variable
912     contains an arbitrary string which corresponds to an already-installed
913     locale. Common names for locales are "en_US.UTF-8", "de_DE.ISO-8859-15",
914     "ja_JP.EUC-JP", i.e. "language_country.encoding", but other forms (i.e.
915     "de" or "german") are also common.
916    
917     Rxvt-unicode ignores all other locale categories, and except for the
918     encoding, ignores country or language-specific settings, i.e.
919     "de_DE.UTF-8" and "ja_JP.UTF-8" are the normally same to rxvt-unicode.
920    
921     If you want to use a specific encoding you have to make sure you start
922     rxvt-unicode with the correct "LC_CTYPE" category.
923    
924     Can I switch locales at runtime?
925     Yes, using an escape sequence. Try something like this, which sets
926     rxvt-unicode's idea of "LC_CTYPE".
927    
928     printf '\33]701;%s\007' ja_JP.SJIS
929    
930     See also the previous answer.
931    
932     Sometimes this capability is rather handy when you want to work in one
933     locale (e.g. "de_DE.UTF-8") but some programs don't support it (e.g.
934     UTF-8). For example, I use this script to start "xjdic", which first
935     switches to a locale supported by xjdic and back later:
936    
937     printf '\33]701;%s\007' ja_JP.SJIS
938     xjdic -js
939     printf '\33]701;%s\007' de_DE.UTF-8
940    
941     You can also use xterm's "luit" program, which usually works fine,
942     except for some locales where character width differs between program-
943     and rxvt-unicode-locales.
944    
945     I have problems getting my input method working.
946     Try a search engine, as this is slightly different for every input
947     method server.
948    
949     Here is a checklist:
950    
951     - Make sure your locale *and* the imLocale are supported on your OS.
952     Try "locale -a" or check the documentation for your OS.
953    
954     - Make sure your locale or imLocale matches a locale supported by your
955     XIM.
956     For example, kinput2 does not support UTF-8 locales, you should use
957     "ja_JP.EUC-JP" or equivalent.
958    
959     - Make sure your XIM server is actually running.
960     - Make sure the "XMODIFIERS" environment variable is set correctly when
961     *starting* rxvt-unicode.
962     When you want to use e.g. kinput2, it must be set to "@im=kinput2".
963 root 1.43 For scim, use "@im=SCIM". You can see what input method servers are
964 root 1.42 running with this command:
965    
966     xprop -root XIM_SERVERS
967    
968 root 1.54
969 root 1.42
970     My input method wants <some encoding> but I want UTF-8, what can I do?
971     You can specify separate locales for the input method and the rest of
972     the terminal, using the resource "imlocale":
973    
974     URxvt.imlocale: ja_JP.EUC-JP
975    
976     Now you can start your terminal with "LC_CTYPE=ja_JP.UTF-8" and still
977     use your input method. Please note, however, that, depending on your
978     Xlib version, you may not be able to input characters outside "EUC-JP"
979     in a normal way then, as your input method limits you.
980    
981     Rxvt-unicode crashes when the X Input Method changes or exits.
982     Unfortunately, this is unavoidable, as the XIM protocol is racy by
983     design. Applications can avoid some crashes at the expense of memory
984     leaks, and Input Methods can avoid some crashes by careful ordering at
985     exit time. kinput2 (and derived input methods) generally succeeds, while
986     SCIM (or similar input methods) fails. In the end, however, crashes
987     cannot be completely avoided even if both sides cooperate.
988    
989     So the only workaround is not to kill your Input Method Servers.
990    
991     Operating Systems / Package Maintaining
992     I am using Debian GNU/Linux and have a problem...
993     The Debian GNU/Linux package of rxvt-unicode in sarge contains large
994     patches that considerably change the behaviour of rxvt-unicode (but
995     unfortunately this notice has been removed). Before reporting a bug to
996     the original rxvt-unicode author please download and install the genuine
997 root 1.63 version (<http://software.schmorp.de/pkg/rxvt-unicode.html>) and try to
998     reproduce the problem. If you cannot, chances are that the problems are
999     specific to Debian GNU/Linux, in which case it should be reported via
1000     the Debian Bug Tracking System (use "reportbug" to report the bug).
1001 root 1.42
1002     For other problems that also affect the Debian package, you can and
1003     probably should use the Debian BTS, too, because, after all, it's also a
1004     bug in the Debian version and it serves as a reminder for other users
1005     that might encounter the same issue.
1006    
1007     I am maintaining rxvt-unicode for distribution/OS XXX, any recommendation?
1008     You should build one binary with the default options. configure now
1009     enables most useful options, and the trend goes to making them
1010 root 1.43 runtime-switchable, too, so there is usually no drawback to enabling
1011 root 1.42 them, except higher disk and possibly memory usage. The perl interpreter
1012     should be enabled, as important functionality (menus, selection, likely
1013     more in the future) depends on it.
1014    
1015 root 1.58 You should not overwrite the "perl-ext-common" and "perl-ext" resources
1016 root 1.42 system-wide (except maybe with "defaults"). This will result in useful
1017     behaviour. If your distribution aims at low memory, add an empty
1018     "perl-ext-common" resource to the app-defaults file. This will keep the
1019     perl interpreter disabled until the user enables it.
1020    
1021     If you can/want build more binaries, I recommend building a minimal one
1022     with "--disable-everything" (very useful) and a maximal one with
1023     "--enable-everything" (less useful, it will be very big due to a lot of
1024     encodings built-in that increase download times and are rarely used).
1025    
1026     I need to make it setuid/setgid to support utmp/ptys on my OS, is this safe?
1027     It should be, starting with release 7.1. You are encouraged to properly
1028     install urxvt with privileges necessary for your OS now.
1029    
1030     When rxvt-unicode detects that it runs setuid or setgid, it will fork
1031     into a helper process for privileged operations (pty handling on some
1032     systems, utmp/wtmp/lastlog handling on others) and drop privileges
1033     immediately. This is much safer than most other terminals that keep
1034     privileges while running (but is more relevant to urxvt, as it contains
1035     things as perl interpreters, which might be "helpful" to attackers).
1036    
1037     This forking is done as the very first within main(), which is very
1038     early and reduces possible bugs to initialisation code run before
1039     main(), or things like the dynamic loader of your system, which should
1040     result in very little risk.
1041    
1042     I am on FreeBSD and rxvt-unicode does not seem to work at all.
1043     Rxvt-unicode requires the symbol "__STDC_ISO_10646__" to be defined in
1044     your compile environment, or an implementation that implements it,
1045 root 1.43 whether it defines the symbol or not. "__STDC_ISO_10646__" requires that
1046 root 1.42 wchar_t is represented as unicode.
1047    
1048 root 1.43 As you might have guessed, FreeBSD does neither define this symbol nor
1049 root 1.42 does it support it. Instead, it uses its own internal representation of
1050     wchar_t. This is, of course, completely fine with respect to standards.
1051    
1052     However, that means rxvt-unicode only works in "POSIX", "ISO-8859-1" and
1053 root 1.55 "UTF-8" locales under FreeBSD (which all use Unicode as wchar_t).
1054 root 1.42
1055     "__STDC_ISO_10646__" is the only sane way to support multi-language apps
1056     in an OS, as using a locale-dependent (and non-standardized)
1057     representation of wchar_t makes it impossible to convert between wchar_t
1058     (as used by X11 and your applications) and any other encoding without
1059     implementing OS-specific-wrappers for each and every locale. There
1060     simply are no APIs to convert wchar_t into anything except the current
1061     locale encoding.
1062    
1063     Some applications (such as the formidable mlterm) work around this by
1064     carrying their own replacement functions for character set handling with
1065     them, and either implementing OS-dependent hacks or doing multiple
1066     conversions (which is slow and unreliable in case the OS implements
1067     encodings slightly different than the terminal emulator).
1068    
1069     The rxvt-unicode author insists that the right way to fix this is in the
1070     system libraries once and for all, instead of forcing every app to carry
1071     complete replacements for them :)
1072    
1073     How can I use rxvt-unicode under cygwin?
1074     rxvt-unicode should compile and run out of the box on cygwin, using the
1075     X11 libraries that come with cygwin. libW11 emulation is no longer
1076     supported (and makes no sense, either, as it only supported a single
1077     font). I recommend starting the X-server in "-multiwindow" or
1078     "-rootless" mode instead, which will result in similar look&feel as the
1079     old libW11 emulation.
1080    
1081     At the time of this writing, cygwin didn't seem to support any
1082     multi-byte encodings (you might try "LC_CTYPE=C-UTF-8"), so you are
1083     likely limited to 8-bit encodings.
1084    
1085 root 1.49 Character widths are not correct.
1086     urxvt uses the system wcwidth function to know the information about the
1087     width of characters, so on systems with incorrect locale data you will
1088     likely get bad results. Two notorious examples are Solaris 9, where
1089     single-width characters like U+2514 are reported as double-width, and
1090     Darwin 8, where combining chars are reported having width 1.
1091    
1092     The solution is to upgrade your system or switch to a better one. A
1093     possibly working workaround is to use a wcwidth implementation like
1094    
1095     http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
1096