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Revision: 1.63
Committed: Mon Dec 13 16:47:27 2010 UTC (13 years, 5 months ago) by root
Branch: MAIN
CVS Tags: rel-9_10
Changes since 1.62: +4 -4 lines
Log Message:
prepare release, fix faq package download url, re-make docs with 5.10 perl

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     editors prematurely may leave the mouse in mouse report mode. I've heard
520     that tcsh may use mouse reporting unless it otherwise specified. A quick
521     check is to see if cut/paste works when the Alt or Shift keys are
522     depressed.
523    
524     What's with the strange Backspace/Delete key behaviour?
525 root 1.43 Assuming that the physical Backspace key corresponds to the Backspace
526 root 1.42 keysym (not likely for Linux ... see the following question) there are
527     two standard values that can be used for Backspace: "^H" and "^?".
528    
529     Historically, either value is correct, but rxvt-unicode adopts the
530 root 1.47 debian policy of using "^?" when unsure, because it's the one and only
531 root 1.42 correct choice :).
532    
533 root 1.60 It is possible to toggle between "^H" and "^?" with the DECBKM private
534     mode:
535 root 1.42
536     # use Backspace = ^H
537     $ stty erase ^H
538 root 1.60 $ echo -n "^[[?67h"
539 root 1.42
540     # use Backspace = ^?
541     $ stty erase ^?
542 root 1.60 $ echo -n "^[[?67l"
543 root 1.42
544     This helps satisfy some of the Backspace discrepancies that occur, but
545     if you use Backspace = "^H", make sure that the termcap/terminfo value
546     properly reflects that.
547    
548     The Delete key is a another casualty of the ill-defined Backspace
549     problem. To avoid confusion between the Backspace and Delete keys, the
550     Delete key has been assigned an escape sequence to match the vt100 for
551     Execute ("ESC [ 3 ~") and is in the supplied termcap/terminfo.
552    
553     Some other Backspace problems:
554    
555     some editors use termcap/terminfo, some editors (vim I'm told) expect
556     Backspace = ^H, GNU Emacs (and Emacs-like editors) use ^H for help.
557    
558     Perhaps someday this will all be resolved in a consistent manner.
559    
560     I don't like the key-bindings. How do I change them?
561     There are some compile-time selections available via configure. Unless
562     you have run "configure" with the "--disable-resources" option you can
563     use the `keysym' resource to alter the keystrings associated with
564     keysyms.
565    
566     Here's an example for a URxvt session started using "urxvt -name URxvt"
567    
568     URxvt.keysym.Home: \033[1~
569     URxvt.keysym.End: \033[4~
570     URxvt.keysym.C-apostrophe: \033<C-'>
571     URxvt.keysym.C-slash: \033<C-/>
572     URxvt.keysym.C-semicolon: \033<C-;>
573     URxvt.keysym.C-grave: \033<C-`>
574     URxvt.keysym.C-comma: \033<C-,>
575     URxvt.keysym.C-period: \033<C-.>
576     URxvt.keysym.C-0x60: \033<C-`>
577     URxvt.keysym.C-Tab: \033<C-Tab>
578     URxvt.keysym.C-Return: \033<C-Return>
579     URxvt.keysym.S-Return: \033<S-Return>
580     URxvt.keysym.S-space: \033<S-Space>
581     URxvt.keysym.M-Up: \033<M-Up>
582     URxvt.keysym.M-Down: \033<M-Down>
583     URxvt.keysym.M-Left: \033<M-Left>
584     URxvt.keysym.M-Right: \033<M-Right>
585     URxvt.keysym.M-C-0: list \033<M-C- 0123456789 >
586     URxvt.keysym.M-C-a: list \033<M-C- abcdefghijklmnopqrstuvwxyz >
587     URxvt.keysym.F12: command:\033]701;zh_CN.GBK\007
588    
589     See some more examples in the documentation for the keysym resource.
590    
591     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
592     KP_Insert == Insert
593     F22 == Print
594     F27 == Home
595     F29 == Prior
596     F33 == End
597     F35 == Next
598    
599     Rather than have rxvt-unicode try to accommodate all the various
600     possible keyboard mappings, it is better to use `xmodmap' to remap the
601     keys as required for your particular machine.
602    
603     Terminal Configuration
604     Can I see a typical configuration?
605     The default configuration tries to be xterm-like, which I don't like
606     that much, but it's least surprise to regular users.
607    
608     As a rxvt or rxvt-unicode user, you are practically supposed to invest
609     time into customising your terminal. To get you started, here is the
610     author's .Xdefaults entries, with comments on what they do. It's
611     certainly not *typical*, but what's typical...
612    
613     URxvt.cutchars: "()*,<>[]{}|'
614     URxvt.print-pipe: cat >/tmp/xxx
615    
616     These are just for testing stuff.
617    
618     URxvt.imLocale: ja_JP.UTF-8
619     URxvt.preeditType: OnTheSpot,None
620    
621     This tells rxvt-unicode to use a special locale when communicating with
622     the X Input Method, and also tells it to only use the OnTheSpot pre-edit
623     type, which requires the "xim-onthespot" perl extension but rewards me
624     with correct-looking fonts.
625    
626     URxvt.perl-lib: /root/lib/urxvt
627     URxvt.perl-ext-common: default,selection-autotransform,selection-pastebin,xim-onthespot,remote-clipboard
628     URxvt.selection.pattern-0: ( at .*? line \\d+)
629     URxvt.selection.pattern-1: ^(/[^:]+):\
630     URxvt.selection-autotransform.0: s/^([^:[:space:]]+):(\\d+):?$/:e \\Q$1\\E\\x0d:$2\\x0d/
631     URxvt.selection-autotransform.1: s/^ at (.*?) line (\\d+)$/:e \\Q$1\\E\\x0d:$2\\x0d/
632    
633     This is my perl configuration. The first two set the perl library
634     directory and also tells urxvt to use a large number of extensions. I
635     develop for myself mostly, so I actually use most of the extensions I
636     write.
637    
638     The selection stuff mainly makes the selection perl-error-message aware
639 root 1.43 and tells it to convert perl error messages into vi-commands to load the
640 root 1.58 relevant file and go to the error line number.
641 root 1.42
642     URxvt.scrollstyle: plain
643     URxvt.secondaryScroll: true
644    
645     As the documentation says: plain is the preferred scrollbar for the
646 root 1.43 author. The "secondaryScroll" configures urxvt to scroll in full-screen
647     apps, like screen, so lines scrolled out of screen end up in urxvt's
648 root 1.42 scrollback buffer.
649    
650     URxvt.background: #000000
651     URxvt.foreground: gray90
652     URxvt.color7: gray90
653     URxvt.colorBD: #ffffff
654     URxvt.cursorColor: #e0e080
655     URxvt.throughColor: #8080f0
656     URxvt.highlightColor: #f0f0f0
657    
658     Some colours. Not sure which ones are being used or even non-defaults,
659     but these are in my .Xdefaults. Most notably, they set
660     foreground/background to light gray/black, and also make sure that the
661     colour 7 matches the default foreground colour.
662    
663     URxvt.underlineColor: yellow
664    
665     Another colour, makes underline lines look different. Sometimes hurts,
666     but is mostly a nice effect.
667    
668     URxvt.geometry: 154x36
669     URxvt.loginShell: false
670     URxvt.meta: ignore
671     URxvt.utmpInhibit: true
672    
673     Uh, well, should be mostly self-explanatory. By specifying some defaults
674     manually, I can quickly switch them for testing.
675    
676     URxvt.saveLines: 8192
677    
678     A large scrollback buffer is essential. Really.
679    
680     URxvt.mapAlert: true
681    
682     The only case I use it is for my IRC window, which I like to keep
683     iconified till people msg me (which beeps).
684    
685     URxvt.visualBell: true
686    
687     The audible bell is often annoying, especially when in a crowd.
688    
689     URxvt.insecure: true
690    
691     Please don't hack my mutt! Ooops...
692    
693     URxvt.pastableTabs: false
694    
695     I once thought this is a great idea.
696    
697     urxvt.font: 9x15bold,\
698     -misc-fixed-bold-r-normal--15-140-75-75-c-90-iso10646-1,\
699     -misc-fixed-medium-r-normal--15-140-75-75-c-90-iso10646-1, \
700     [codeset=JISX0208]xft:Kochi Gothic, \
701     xft:Bitstream Vera Sans Mono:autohint=true, \
702     xft:Code2000:antialias=false
703     urxvt.boldFont: -xos4-terminus-bold-r-normal--14-140-72-72-c-80-iso8859-15
704     urxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
705     urxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
706    
707     I wrote rxvt-unicode to be able to specify fonts exactly. So don't be
708 root 1.43 overwhelmed. A special note: the "9x15bold" mentioned above is actually
709 root 1.42 the version from XFree-3.3, as XFree-4 replaced it by a totally
710     different font (different glyphs for ";" and many other harmless
711     characters), while the second font is actually the "9x15bold" from
712     XFree4/XOrg. The bold version has less chars than the medium version, so
713 root 1.43 I use it for rare characters, too. When editing sources with vim, I use
714 root 1.42 italic for comments and other stuff, which looks quite good with
715     Bitstream Vera anti-aliased.
716    
717     Terminus is a quite bad font (many very wrong glyphs), but for most of
718     my purposes, it works, and gives a different look, as my normal
719     (Non-bold) font is already bold, and I want to see a difference between
720     bold and normal fonts.
721    
722     Please note that I used the "urxvt" instance name and not the "URxvt"
723 root 1.58 class name. That is because I use different configs for different
724 root 1.42 purposes, for example, my IRC window is started with "-name IRC", and
725     uses these defaults:
726    
727     IRC*title: IRC
728     IRC*geometry: 87x12+535+542
729     IRC*saveLines: 0
730     IRC*mapAlert: true
731     IRC*font: suxuseuro
732     IRC*boldFont: suxuseuro
733     IRC*colorBD: white
734     IRC*keysym.M-C-1: command:\033]710;suxuseuro\007\033]711;suxuseuro\007
735     IRC*keysym.M-C-2: command:\033]710;9x15bold\007\033]711;9x15bold\007
736    
737 root 1.57 "Alt-Ctrl-1" and "Alt-Ctrl-2" switch between two different font sizes.
738 root 1.42 "suxuseuro" allows me to keep an eye (and actually read) stuff while
739     keeping a very small window. If somebody pastes something complicated
740     (e.g. japanese), I temporarily switch to a larger font.
741    
742     The above is all in my ".Xdefaults" (I don't use ".Xresources" nor
743     "xrdb"). I also have some resources in a separate ".Xdefaults-hostname"
744 root 1.60 file for different hosts, for example, on my main desktop, I use:
745 root 1.42
746     URxvt.keysym.C-M-q: command:\033[3;5;5t
747     URxvt.keysym.C-M-y: command:\033[3;5;606t
748     URxvt.keysym.C-M-e: command:\033[3;1605;5t
749     URxvt.keysym.C-M-c: command:\033[3;1605;606t
750     URxvt.keysym.C-M-p: perl:test
751    
752     The first for keysym definitions allow me to quickly bring some windows
753     in the layout I like most. Ion users might start laughing but will stop
754     immediately when I tell them that I use my own Fvwm2 module for much the
755     same effect as Ion provides, and I only very rarely use the above key
756     combinations :->
757    
758     Why doesn't rxvt-unicode read my resources?
759     Well, why, indeed? It does, in a way very similar to other X
760     applications. Most importantly, this means that if you or your OS loads
761     resources into the X display (the right way to do it), rxvt-unicode will
762     ignore any resource files in your home directory. It will only read
763     $HOME/.Xdefaults when no resources are attached to the display.
764    
765     If you have or use an $HOME/.Xresources file, chances are that resources
766     are loaded into your X-server. In this case, you have to re-login after
767     every change (or run xrdb -merge $HOME/.Xresources).
768    
769     Also consider the form resources have to use:
770    
771     URxvt.resource: value
772    
773     If you want to use another form (there are lots of different ways of
774 root 1.43 specifying resources), make sure you understand whether and why it
775     works. If unsure, use the form above.
776 root 1.42
777     When I log-in to another system it tells me about missing terminfo data?
778     The terminal description used by rxvt-unicode is not as widely available
779     as that for xterm, or even rxvt (for which the same problem often
780     arises).
781    
782     The correct solution for this problem is to install the terminfo, this
783 root 1.57 can be done by simply installing rxvt-unicode on the remote system as
784     well (in case you have a nice package manager ready), or you can install
785     the terminfo database manually like this (with ncurses infocmp. works as
786     user and root):
787 root 1.42
788     REMOTE=remotesystem.domain
789 root 1.44 infocmp rxvt-unicode | ssh $REMOTE "mkdir -p .terminfo && cat >/tmp/ti && tic /tmp/ti"
790 root 1.42
791 root 1.44 One some systems you might need to set $TERMINFO to the full path of
792     $HOME/.terminfo for this to work.
793    
794 root 1.42 If you cannot or do not want to do this, then you can simply set
795     "TERM=rxvt" or even "TERM=xterm", and live with the small number of
796     problems arising, which includes wrong keymapping, less and different
797     colours and some refresh errors in fullscreen applications. It's a nice
798     quick-and-dirty workaround for rare cases, though.
799    
800     If you always want to do this (and are fine with the consequences) you
801     can either recompile rxvt-unicode with the desired TERM value or use a
802     resource to set it:
803    
804     URxvt.termName: rxvt
805    
806     If you don't plan to use rxvt (quite common...) you could also replace
807     the rxvt terminfo file with the rxvt-unicode one and use "TERM=rxvt".
808    
809 root 1.57 nano fails with "Error opening terminal: rxvt-unicode"
810     This exceptionally confusing and useless error message is printed by
811     nano when it can't find the terminfo database. Nothing is wrong with
812     your terminal, read the previous answer for a solution.
813    
814 root 1.42 "tic" outputs some error when compiling the terminfo entry.
815     Most likely it's the empty definition for "enacs=". Just replace it by
816     "enacs=\E[0@" and try again.
817    
818     "bash"'s readline does not work correctly under urxvt.
819     See next entry.
820    
821     I need a termcap file entry.
822     One reason you might want this is that some distributions or operating
823     systems still compile some programs using the long-obsoleted termcap
824     library (Fedora Core's bash is one example) and rely on a termcap entry
825     for "rxvt-unicode".
826    
827 root 1.43 You could use rxvt's termcap entry with reasonable results in many
828     cases. You can also create a termcap entry by using terminfo's infocmp
829     program like this:
830 root 1.42
831     infocmp -C rxvt-unicode
832    
833 root 1.55 Or you could use the termcap entry in doc/etc/rxvt-unicode.termcap,
834     generated by the command above.
835 root 1.42
836     Why does "ls" no longer have coloured output?
837     The "ls" in the GNU coreutils unfortunately doesn't use terminfo to
838 root 1.43 decide whether a terminal has colour, but uses its own configuration
839 root 1.42 file. Needless to say, "rxvt-unicode" is not in its default file (among
840     with most other terminals supporting colour). Either add:
841    
842     TERM rxvt-unicode
843    
844     to "/etc/DIR_COLORS" or simply add:
845    
846     alias ls='ls --color=auto'
847    
848     to your ".profile" or ".bashrc".
849    
850     Why doesn't vim/emacs etc. use the 88 colour mode?
851     See next entry.
852    
853     Why doesn't vim/emacs etc. make use of italic?
854     See next entry.
855    
856     Why are the secondary screen-related options not working properly?
857     Make sure you are using "TERM=rxvt-unicode". Some pre-packaged
858     distributions (most notably Debian GNU/Linux) break rxvt-unicode by
859     setting "TERM" to "rxvt", which doesn't have these extra features.
860     Unfortunately, some of these (most notably, again, Debian GNU/Linux)
861     furthermore fail to even install the "rxvt-unicode" terminfo file, so
862     you will need to install it on your own (See the question When I log-in
863     to another system it tells me about missing terminfo data? on how to do
864     this).
865    
866     Encoding / Locale / Input Method Issues
867     Rxvt-unicode does not seem to understand the selected encoding?
868     See next entry.
869    
870     Unicode does not seem to work?
871     If you encounter strange problems like typing an accented character but
872     getting two unrelated other characters or similar, or if program output
873     is subtly garbled, then you should check your locale settings.
874    
875     Rxvt-unicode must be started with the same "LC_CTYPE" setting as the
876 root 1.46 programs running in it. Often rxvt-unicode is started in the "C" locale,
877     while the login script running within the rxvt-unicode window changes
878     the locale to something else, e.g. "en_GB.UTF-8". Needless to say, this
879     is not going to work, and is the most common cause for problems.
880 root 1.42
881     The best thing is to fix your startup environment, as you will likely
882     run into other problems. If nothing works you can try this in your
883     .profile.
884    
885 root 1.46 printf '\33]701;%s\007' "$LC_CTYPE" # $LANG or $LC_ALL are worth a try, too
886 root 1.42
887     If this doesn't work, then maybe you use a "LC_CTYPE" specification not
888     supported on your systems. Some systems have a "locale" command which
889     displays this (also, "perl -e0" can be used to check locale settings, as
890     it will complain loudly if it cannot set the locale). If it displays
891     something like:
892    
893     locale: Cannot set LC_CTYPE to default locale: ...
894    
895     Then the locale you specified is not supported on your system.
896    
897     If nothing works and you are sure that everything is set correctly then
898     you will need to remember a little known fact: Some programs just don't
899     support locales :(
900    
901     How does rxvt-unicode determine the encoding to use?
902     See next entry.
903    
904     Is there an option to switch encodings?
905     Unlike some other terminals, rxvt-unicode has no encoding switch, and no
906     specific "utf-8" mode, such as xterm. In fact, it doesn't even know
907     about UTF-8 or any other encodings with respect to terminal I/O.
908    
909     The reasons is that there exists a perfectly fine mechanism for
910     selecting the encoding, doing I/O and (most important) communicating
911     this to all applications so everybody agrees on character properties
912     such as width and code number. This mechanism is the *locale*.
913     Applications not using that info will have problems (for example,
914     "xterm" gets the width of characters wrong as it uses its own,
915     locale-independent table under all locales).
916    
917     Rxvt-unicode uses the "LC_CTYPE" locale category to select encoding. All
918     programs doing the same (that is, most) will automatically agree in the
919     interpretation of characters.
920    
921     Unfortunately, there is no system-independent way to select locales, nor
922     is there a standard on how locale specifiers will look like.
923    
924     On most systems, the content of the "LC_CTYPE" environment variable
925     contains an arbitrary string which corresponds to an already-installed
926     locale. Common names for locales are "en_US.UTF-8", "de_DE.ISO-8859-15",
927     "ja_JP.EUC-JP", i.e. "language_country.encoding", but other forms (i.e.
928     "de" or "german") are also common.
929    
930     Rxvt-unicode ignores all other locale categories, and except for the
931     encoding, ignores country or language-specific settings, i.e.
932     "de_DE.UTF-8" and "ja_JP.UTF-8" are the normally same to rxvt-unicode.
933    
934     If you want to use a specific encoding you have to make sure you start
935     rxvt-unicode with the correct "LC_CTYPE" category.
936    
937     Can I switch locales at runtime?
938     Yes, using an escape sequence. Try something like this, which sets
939     rxvt-unicode's idea of "LC_CTYPE".
940    
941     printf '\33]701;%s\007' ja_JP.SJIS
942    
943     See also the previous answer.
944    
945     Sometimes this capability is rather handy when you want to work in one
946     locale (e.g. "de_DE.UTF-8") but some programs don't support it (e.g.
947     UTF-8). For example, I use this script to start "xjdic", which first
948     switches to a locale supported by xjdic and back later:
949    
950     printf '\33]701;%s\007' ja_JP.SJIS
951     xjdic -js
952     printf '\33]701;%s\007' de_DE.UTF-8
953    
954     You can also use xterm's "luit" program, which usually works fine,
955     except for some locales where character width differs between program-
956     and rxvt-unicode-locales.
957    
958     I have problems getting my input method working.
959     Try a search engine, as this is slightly different for every input
960     method server.
961    
962     Here is a checklist:
963    
964     - Make sure your locale *and* the imLocale are supported on your OS.
965     Try "locale -a" or check the documentation for your OS.
966    
967     - Make sure your locale or imLocale matches a locale supported by your
968     XIM.
969     For example, kinput2 does not support UTF-8 locales, you should use
970     "ja_JP.EUC-JP" or equivalent.
971    
972     - Make sure your XIM server is actually running.
973     - Make sure the "XMODIFIERS" environment variable is set correctly when
974     *starting* rxvt-unicode.
975     When you want to use e.g. kinput2, it must be set to "@im=kinput2".
976 root 1.43 For scim, use "@im=SCIM". You can see what input method servers are
977 root 1.42 running with this command:
978    
979     xprop -root XIM_SERVERS
980    
981 root 1.54
982 root 1.42
983     My input method wants <some encoding> but I want UTF-8, what can I do?
984     You can specify separate locales for the input method and the rest of
985     the terminal, using the resource "imlocale":
986    
987     URxvt.imlocale: ja_JP.EUC-JP
988    
989     Now you can start your terminal with "LC_CTYPE=ja_JP.UTF-8" and still
990     use your input method. Please note, however, that, depending on your
991     Xlib version, you may not be able to input characters outside "EUC-JP"
992     in a normal way then, as your input method limits you.
993    
994     Rxvt-unicode crashes when the X Input Method changes or exits.
995     Unfortunately, this is unavoidable, as the XIM protocol is racy by
996     design. Applications can avoid some crashes at the expense of memory
997     leaks, and Input Methods can avoid some crashes by careful ordering at
998     exit time. kinput2 (and derived input methods) generally succeeds, while
999     SCIM (or similar input methods) fails. In the end, however, crashes
1000     cannot be completely avoided even if both sides cooperate.
1001    
1002     So the only workaround is not to kill your Input Method Servers.
1003    
1004     Operating Systems / Package Maintaining
1005     I am using Debian GNU/Linux and have a problem...
1006     The Debian GNU/Linux package of rxvt-unicode in sarge contains large
1007     patches that considerably change the behaviour of rxvt-unicode (but
1008     unfortunately this notice has been removed). Before reporting a bug to
1009     the original rxvt-unicode author please download and install the genuine
1010 root 1.63 version (<http://software.schmorp.de/pkg/rxvt-unicode.html>) and try to
1011     reproduce the problem. If you cannot, chances are that the problems are
1012     specific to Debian GNU/Linux, in which case it should be reported via
1013     the Debian Bug Tracking System (use "reportbug" to report the bug).
1014 root 1.42
1015     For other problems that also affect the Debian package, you can and
1016     probably should use the Debian BTS, too, because, after all, it's also a
1017     bug in the Debian version and it serves as a reminder for other users
1018     that might encounter the same issue.
1019    
1020     I am maintaining rxvt-unicode for distribution/OS XXX, any recommendation?
1021     You should build one binary with the default options. configure now
1022     enables most useful options, and the trend goes to making them
1023 root 1.43 runtime-switchable, too, so there is usually no drawback to enabling
1024 root 1.42 them, except higher disk and possibly memory usage. The perl interpreter
1025     should be enabled, as important functionality (menus, selection, likely
1026     more in the future) depends on it.
1027    
1028 root 1.58 You should not overwrite the "perl-ext-common" and "perl-ext" resources
1029 root 1.42 system-wide (except maybe with "defaults"). This will result in useful
1030     behaviour. If your distribution aims at low memory, add an empty
1031     "perl-ext-common" resource to the app-defaults file. This will keep the
1032     perl interpreter disabled until the user enables it.
1033    
1034     If you can/want build more binaries, I recommend building a minimal one
1035     with "--disable-everything" (very useful) and a maximal one with
1036     "--enable-everything" (less useful, it will be very big due to a lot of
1037     encodings built-in that increase download times and are rarely used).
1038    
1039     I need to make it setuid/setgid to support utmp/ptys on my OS, is this safe?
1040     It should be, starting with release 7.1. You are encouraged to properly
1041     install urxvt with privileges necessary for your OS now.
1042    
1043     When rxvt-unicode detects that it runs setuid or setgid, it will fork
1044     into a helper process for privileged operations (pty handling on some
1045     systems, utmp/wtmp/lastlog handling on others) and drop privileges
1046     immediately. This is much safer than most other terminals that keep
1047     privileges while running (but is more relevant to urxvt, as it contains
1048     things as perl interpreters, which might be "helpful" to attackers).
1049    
1050     This forking is done as the very first within main(), which is very
1051     early and reduces possible bugs to initialisation code run before
1052     main(), or things like the dynamic loader of your system, which should
1053     result in very little risk.
1054    
1055     I am on FreeBSD and rxvt-unicode does not seem to work at all.
1056     Rxvt-unicode requires the symbol "__STDC_ISO_10646__" to be defined in
1057     your compile environment, or an implementation that implements it,
1058 root 1.43 whether it defines the symbol or not. "__STDC_ISO_10646__" requires that
1059 root 1.42 wchar_t is represented as unicode.
1060    
1061 root 1.43 As you might have guessed, FreeBSD does neither define this symbol nor
1062 root 1.42 does it support it. Instead, it uses its own internal representation of
1063     wchar_t. This is, of course, completely fine with respect to standards.
1064    
1065     However, that means rxvt-unicode only works in "POSIX", "ISO-8859-1" and
1066 root 1.55 "UTF-8" locales under FreeBSD (which all use Unicode as wchar_t).
1067 root 1.42
1068     "__STDC_ISO_10646__" is the only sane way to support multi-language apps
1069     in an OS, as using a locale-dependent (and non-standardized)
1070     representation of wchar_t makes it impossible to convert between wchar_t
1071     (as used by X11 and your applications) and any other encoding without
1072     implementing OS-specific-wrappers for each and every locale. There
1073     simply are no APIs to convert wchar_t into anything except the current
1074     locale encoding.
1075    
1076     Some applications (such as the formidable mlterm) work around this by
1077     carrying their own replacement functions for character set handling with
1078     them, and either implementing OS-dependent hacks or doing multiple
1079     conversions (which is slow and unreliable in case the OS implements
1080     encodings slightly different than the terminal emulator).
1081    
1082     The rxvt-unicode author insists that the right way to fix this is in the
1083     system libraries once and for all, instead of forcing every app to carry
1084     complete replacements for them :)
1085    
1086     How can I use rxvt-unicode under cygwin?
1087     rxvt-unicode should compile and run out of the box on cygwin, using the
1088     X11 libraries that come with cygwin. libW11 emulation is no longer
1089     supported (and makes no sense, either, as it only supported a single
1090     font). I recommend starting the X-server in "-multiwindow" or
1091     "-rootless" mode instead, which will result in similar look&feel as the
1092     old libW11 emulation.
1093    
1094     At the time of this writing, cygwin didn't seem to support any
1095     multi-byte encodings (you might try "LC_CTYPE=C-UTF-8"), so you are
1096     likely limited to 8-bit encodings.
1097    
1098 root 1.49 Character widths are not correct.
1099     urxvt uses the system wcwidth function to know the information about the
1100     width of characters, so on systems with incorrect locale data you will
1101     likely get bad results. Two notorious examples are Solaris 9, where
1102     single-width characters like U+2514 are reported as double-width, and
1103     Darwin 8, where combining chars are reported having width 1.
1104    
1105     The solution is to upgrade your system or switch to a better one. A
1106     possibly working workaround is to use a wcwidth implementation like
1107    
1108     http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
1109