-FREQUENTLY ASKED QUESTIONS
- How do I know which rxvt-unicode version I'm using?
- The version number is displayed with the usage (-h). Also the escape
- sequence "ESC [ 8 n" sets the window title to the version number.
-
- I am using Debian GNU/Linux and have a problem...
- The Debian GNU/Linux package of rxvt-unicode contains large patches
- that considerably change the behaviour of rxvt-unicode. Before
- reporting a bug to the original rxvt-unicode author please download
- and install the genuine version
- (<http://software.schmorp.de#rxvt-unicode>) and try to reproduce the
- problem. If you cannot, chances are that the problems are specific
- to Debian GNU/Linux, in which case it should be reported via the
- Debian Bug Tracking System (use "reportbug" to report the bug).
-
- For other problems that also affect the Debian package, you can and
- probably should use the Debian BTS, too, because, after all, it's
- also a bug in the Debian version and it serves as a reminder for
- other users that might encounter the same issue.
-
- When I log-in to another system it tells me about missing terminfo data?
- The terminal description used by rxvt-unicode is not as widely
- available as that for xterm, or even rxvt (for which the same
- problem often arises).
-
- The correct solution for this problem is to install the terminfo,
- this can be done like this (with ncurses' infocmp):
-
- REMOTE=remotesystem.domain
- infocmp rxvt-unicode | ssh $REMOTE "cat >/tmp/ti && tic /tmp/ti"
-
- ... or by installing rxvt-unicode normally on the remote system,
-
- If you cannot or do not want to do this, then you can simply set
- "TERM=rxvt" or even "TERM=xterm", and live with the small number of
- problems arising, which includes wrong keymapping, less and
- different colours and some refresh errors in fullscreen
- applications. It's a nice quick-and-dirty workaround for rare cases,
- though.
-
- If you always want to do this (and are fine with the consequences)
- you can either recompile rxvt-unicode with the desired TERM value or
- use a resource to set it:
-
- URxvt.termName: rxvt
-
- If you don't plan to use rxvt (quite common...) you could also
- replace the rxvt terminfo file with the rxvt-unicode one.
-
- "bash"'s readline does not work correctly under rxvt.
- I need a termcap file entry.
- One reason you might want this is that some distributions or
- operating systems still compile some programs using the
- long-obsoleted termcap (Fedora Core's bash is one example) and rely
- on a termcap entry for "rxvt-unicode".
-
- You could use rxvt's termcap entry with resonable results in many
- cases. You can also create a termcap entry by using terminfo's
- infocmp program like this:
-
- infocmp -C rxvt-unicode
-
- Or you could use this termcap entry, generated by the command above:
-
- rxvt-unicode|rxvt-unicode terminal (X Window System):\
- :am:bw:eo:km:mi:ms:xn:xo:\
- :co#80:it#8:li#24:\
- :AL=\E[%dL:DC=\E[%dP:DL=\E[%dM:DO=\E[%dB:IC=\E[%d@:\
- :K1=\EOw:K2=\EOu:K3=\EOy:K4=\EOq:K5=\EOs:LE=\E[%dD:\
- :RI=\E[%dC:SF=\E[%dS:SR=\E[%dT:UP=\E[%dA:ae=^O:al=\E[L:\
- :as=^N:bl=^G:cd=\E[J:ce=\E[K:cl=\E[H\E[2J:cm=\E[%i%d;%dH:\
- :cr=^M:cs=\E[%i%d;%dr:ct=\E[3g:dc=\E[P:dl=\E[M:do=^J:\
- :ec=\E[%dX:ei=\E[4l:ho=\E[H:i1=\E[?47l\E=\E[?1l:ic=\E[@:\
- :im=\E[4h:is=\E[r\E[m\E[2J\E[H\E[?7h\E[?1;3;4;6l\E[4l:\
- :k0=\E[21~:k1=\E[11~:k2=\E[12~:k3=\E[13~:k4=\E[14~:\
- :k5=\E[15~:k6=\E[17~:k7=\E[18~:k8=\E[19~:k9=\E[20~:\
- :kD=\E[3~:kI=\E[2~:kN=\E[6~:kP=\E[5~:kb=\177:kd=\EOB:\
- :ke=\E[?1l\E>:kh=\E[7~:kl=\EOD:kr=\EOC:ks=\E[?1h\E=:\
- :ku=\EOA:le=^H:mb=\E[5m:md=\E[1m:me=\E[m\017:mr=\E[7m:\
- :nd=\E[C:rc=\E8:sc=\E7:se=\E[27m:sf=^J:so=\E[7m:sr=\EM:\
- :st=\EH:ta=^I:te=\E[r\E[?1049l:ti=\E[?1049h:ue=\E[24m:\
- :up=\E[A:us=\E[4m:vb=\E[?5h\E[?5l:ve=\E[?25h:vi=\E[?25l:\
- :vs=\E[?25h:
-
- Why does "ls" no longer have coloured output?
- The "ls" in the GNU coreutils unfortunately doesn't use terminfo to
- decide wether a terminal has colour, but uses it's own configuration
- file. Needless to say, "rxvt-unicode" is not in it's default file
- (among with most other terminals supporting colour). Either add:
-
- TERM rxvt-unicode
-
- to "/etc/DIR_COLORS" or simply add:
-
- alias ls='ls --color=auto'
-
- to your ".profile" or ".bashrc".
-
- Why doesn't vim/emacs etc. use the 88 colour mode?
- Why doesn't vim/emacs etc. make use of italic?
- Why are the secondary screen-related options not working properly?
- Make sure you are using "TERM=rxvt-unicode". Some pre-packaged
- distributions (most notably Debian GNU/Linux) break rxvt-unicode by
- setting "TERM" to "rxvt", which doesn't have these extra features.
- Unfortunately, some of these (most notably, again, Debian GNU/Linux)
- furthermore fail to even install the "rxvt-unicode" terminfo file,
- so you will need to install it on your own (See the question When I
- log-in to another system it tells me about missing terminfo data? on
- how to do this).
-
- My numerical keypad acts weird and generates differing output?
- Some Debian GNUL/Linux users seem to have this problem, although no
- specific details were reported so far. It is possible that this is
- caused by the wrong "TERM" setting, although the details of wether
- and how this can happen are unknown, as "TERM=rxvt" should offer a
- compatible keymap. See the answer to the previous question, and
- please report if that helped.
-
- Rxvt-unicode does not seem to understand the selected encoding?
- Unicode does not seem to work?
- If you encounter strange problems like typing an accented character
- but getting two unrelated other characters or similar, or if program
- output is subtly garbled, then you should check your locale
- settings.
-
- Rxvt-unicode must be started with the same "LC_CTYPE" setting as the
- programs. Often rxvt-unicode is started in the "C" locale, while the
- login script running within the rxvt-unicode window changes the
- locale to something else, e.g. "en_GB.UTF-8". Needless to say, this
- is not going to work.
-
- The best thing is to fix your startup environment, as you will
- likely run into other problems. If nothing works you can try this in
- your .profile.
-
- printf '\e]701;%s\007' "$LC_CTYPE"
-
- If this doesn't work, then maybe you use a "LC_CTYPE" specification
- not supported on your systems. Some systems have a "locale" command
- which displays this (also, "perl -e0" can be used to check locale
- settings, as it will complain loudly if it cannot set the locale).
- If it displays something like:
-
- locale: Cannot set LC_CTYPE to default locale: ...
-
- Then the locale you specified is not supported on your system.
-
- If nothing works and you are sure that everything is set correctly
- then you will need to remember a little known fact: Some programs
- just don't support locales :(
-
- Why do some characters look so much different than others?
- How does rxvt-unicode choose fonts?
- Most fonts do not contain the full range of Unicode, which is fine.
- Chances are that the font you (or the admin/package maintainer of
- your system/os) have specified does not cover all the characters you
- want to display.
-
- rxvt-unicode makes a best-effort try at finding a replacement font.
- Often the result is fine, but sometimes the chosen font looks
- bad/ugly/wrong. Some fonts have totally strange characters that
- don't resemble the correct glyph at all, and rxvt-unicode lacks the
- artificial intelligence to detect that a specific glyph is wrong: it
- has to believe the font that the characters it claims to contain
- indeed look correct.
-
- In that case, select a font of your taste and add it to the font
- list, e.g.:
-
- rxvt -fn basefont,font2,font3...
-
- When rxvt-unicode sees a character, it will first look at the base
- font. If the base font does not contain the character, it will go to
- the next font, and so on. Specifying your own fonts will also speed
- up this search and use less resources within rxvt-unicode and the
- X-server.
-
- The only limitation is that none of the fonts may be larger than the
- base font, as the base font defines the terminal character cell
- size, which must be the same due to the way terminals work.
-
- Why do some chinese characters look so different than others?
- This is because there is a difference between script and language --
- rxvt-unicode does not know which language the text that is output
- is, as it only knows the unicode character codes. If rxvt-unicode
- first sees a japanese/chinese character, it might choose a japanese
- font for display. Subsequent japanese characters will use that font.
- Now, many chinese characters aren't represented in japanese fonts,
- so when the first non-japanese character comes up, rxvt-unicode will
- look for a chinese font -- unfortunately at this point, it will
- still use the japanese font for chinese characters that are also in
- the japanese font.
-
- The workaround is easy: just tag a chinese font at the end of your
- font list (see the previous question). The key is to view the font
- list as a preference list: If you expect more japanese, list a
- japanese font first. If you expect more chinese, put a chinese font
- first.
-
- In the future it might be possible to switch language preferences at
- runtime (the internal data structure has no problem with using
- different fonts for the same character at the same time, but no
- interface for this has been designed yet).
-
- Until then, you might get away with switching fonts at runtime (see
- "Can I switch the fonts at runtime?" later in this document).
-
- Why does rxvt-unicode sometimes leave pixel droppings?
- Most fonts were not designed for terminal use, which means that
- character size varies a lot. A font that is otherwise fine for
- terminal use might contain some characters that are simply too wide.
- Rxvt-unicode will avoid these characters. For characters that are
- just "a bit" too wide a special "careful" rendering mode is used
- that redraws adjacent characters.
-
- All of this requires that fonts do not lie about character sizes,
- however: Xft fonts often draw glyphs larger than their acclaimed
- bounding box, and rxvt-unicode has no way of detecting this (the
- correct way is to ask for the character bounding box, which
- unfortunately is wrong in these cases).
-
- It's not clear (to me at least), wether this is a bug in Xft,
- freetype, or the respective font. If you encounter this problem you
- might try using the "-lsp" option to give the font more height. If
- that doesn't work, you might be forced to use a different font.
-
- All of this is not a problem when using X11 core fonts, as their
- bounding box data is correct.
-
- My Compose (Multi_key) key is no longer working.
- The most common causes for this are that either your locale is not
- set correctly, or you specified a preeditStyle that is not supported
- by your input method. For example, if you specified OverTheSpot and
- your input method (e.g. the default input method handling Compose
- keys) does not support this (for instance because it is not visual),
- then rxvt-unicode will continue without an input method.
-
- In this case either do not specify a preeditStyle or specify more
- than one pre-edit style, such as OverTheSpot,Root,None.
-
- I cannot type "Ctrl-Shift-2" to get an ASCII NUL character due to ISO
- 14755
- Either try "Ctrl-2" alone (it often is mapped to ASCII NUL even on
- international keyboards) or simply use ISO 14755 support to your
- advantage, typing <Ctrl-Shift-0> to get a ASCII NUL. This works for
- other codes, too, such as "Ctrl-Shift-1-d" to type the default
- telnet escape character and so on.
-
- How can I keep rxvt-unicode from using reverse video so much?
- First of all, make sure you are running with the right terminal
- settings ("TERM=rxvt-unicode"), which will get rid of most of these
- effects. Then make sure you have specified colours for italic and
- bold, as otherwise rxvt-unicode might use reverse video to simulate
- the effect:
-
- URxvt.colorBD: white
- URxvt.colorIT: green
-
- Some programs assume totally weird colours (red instead of blue), how
- can I fix that?
- For some unexplainable reason, some rare programs assume a very
- weird colour palette when confronted with a terminal with more than
- the standard 8 colours (rxvt-unicode supports 88). The right fix is,
- of course, to fix these programs not to assume non-ISO colours
- without very good reasons.
-
- In the meantime, you can either edit your "rxvt-unicode" terminfo
- definition to only claim 8 colour support or use "TERM=rxvt", which
- will fix colours but keep you from using other rxvt-unicode
- features.
-
- I am on FreeBSD and rxvt-unicode does not seem to work at all.
- Rxvt-unicode requires the symbol "__STDC_ISO_10646__" to be defined
- in your compile environment, or an implementation that implements
- it, wether it defines the symbol or not. "__STDC_ISO_10646__"
- requires that wchar_t is represented as unicode.
-
- As you might have guessed, FreeBSD does neither define this symobl
- nor does it support it. Instead, it uses it's own internal
- representation of wchar_t. This is, of course, completely fine with
- respect to standards.
-
- However, "__STDC_ISO_10646__" is the only sane way to support
- multi-language apps in an OS, as using a locale-dependent (and
- non-standardized) representation of wchar_t makes it impossible to
- convert between wchar_t (as used by X11 and your applications) and
- any other encoding without implementing OS-specific-wrappers for
- each and every locale. There simply are no APIs to convert wchar_t
- into anything except the current locale encoding.
-
- Some applications (such as the formidable mlterm) work around this
- by carrying their own replacement functions for character set
- handling with them, and either implementing OS-dependent hacks or
- doing multiple conversions (which is slow and unreliable in case the
- OS implements encodings slightly different than the terminal
- emulator).
-
- The rxvt-unicode author insists that the right way to fix this is in
- the system libraries once and for all, instead of forcing every app
- to carry complete replacements for them :)
-
- How does rxvt-unicode determine the encoding to use?
- Is there an option to switch encodings?
- Unlike some other terminals, rxvt-unicode has no encoding switch,
- and no specific "utf-8" mode, such as xterm. In fact, it doesn't
- even know about UTF-8 or any other encodings with respect to
- terminal I/O.
-
- The reasons is that there exists a perfectly fine mechanism for
- selecting the encoding, doing I/O and (most important) communicating
- this to all applications so everybody agrees on character properties
- such as width and code number. This mechanism is the *locale*.
- Applications not using that info will have problems (for example,
- "xterm" gets the width of characters wrong as it uses it's own,
- locale-independent table under all locales).
-
- Rxvt-unicode uses the "LC_CTYPE" locale category to select encoding.
- All programs doing the same (that is, most) will automatically agree
- in the interpretation of characters.
-
- Unfortunately, there is no system-independent way to select locales,
- nor is there a standard on how locale specifiers will look like.
-
- On most systems, the content of the "LC_CTYPE" environment variable
- contains an arbitrary string which corresponds to an
- already-installed locale. Common names for locales are
- "en_US.UTF-8", "de_DE.ISO-8859-15", "ja_JP.EUC-JP", i.e.
- "language_country.encoding", but other forms (i.e. "de" or "german")
- are also common.
-
- Rxvt-unicode ignores all other locale categories, and except for the
- encoding, ignores country or language-specific settings, i.e.
- "de_DE.UTF-8" and "ja_JP.UTF-8" are the normally same to
- rxvt-unicode.
-
- If you want to use a specific encoding you have to make sure you
- start rxvt-unicode with the correct "LC_CTYPE" category.
-
- Can I switch locales at runtime?
- Yes, using an escape sequence. Try something like this, which sets
- rxvt-unicode's idea of "LC_CTYPE".
-
- printf '\e]701;%s\007' ja_JP.SJIS
-
- See also the previous answer.
-
- Sometimes this capability is rather handy when you want to work in
- one locale (e.g. "de_DE.UTF-8") but some programs don't support it
- (e.g. UTF-8). For example, I use this script to start "xjdic", which
- first switches to a locale supported by xjdic and back later:
-
- printf '\e]701;%s\007' ja_JP.SJIS
- xjdic -js
- printf '\e]701;%s\007' de_DE.UTF-8
-
- You can also use xterm's "luit" program, which usually works fine,
- except for some locales where character width differs between
- program- and rxvt-unicode-locales.
-
- Can I switch the fonts at runtime?
- Yes, using an escape sequence. Try something like this, which has
- the same effect as using the "-fn" switch, and takes effect
- immediately:
-
- printf '\e]50;%s\007' "9x15bold,xft:Kochi Gothic"
-
- This is useful if you e.g. work primarily with japanese (and prefer
- a japanese font), but you have to switch to chinese temporarily,
- where japanese fonts would only be in your way.
-
- You can think of this as a kind of manual ISO-2022 switching.
-
- Why do italic characters look as if clipped?
- Many fonts have difficulties with italic characters and hinting. For
- example, the otherwise very nicely hinted font "xft:Bitstream Vera
- Sans Mono" completely fails in it's italic face. A workaround might
- be to enable freetype autohinting, i.e. like this:
-
- URxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
- URxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
-
- My input method wants <some encoding> but I want UTF-8, what can I do?
- You can specify separate locales for the input method and the rest
- of the terminal, using the resource "imlocale":
-
- URxvt*imlocale: ja_JP.EUC-JP
-
- Now you can start your terminal with "LC_CTYPE=ja_JP.UTF-8" and
- still use your input method. Please note, however, that you will not
- be able to input characters outside "EUC-JP" in a normal way then,
- as your input method limits you.
-
- Rxvt-unicode crashes when the X Input Method changes or exits.
- Unfortunately, this is unavoidable, as the XIM protocol is racy by
- design. Applications can avoid some crashes at the expense of memory
- leaks, and Input Methods can avoid some crashes by careful ordering
- at exit time. kinput2 (and derived input methods) generally
- succeeds, while SCIM (or similar input methods) fails. In the end,
- however, crashes cannot be completely avoided even if both sides
- cooperate.
-
- So the only workaround is not to kill your Input Method Servers.
-
- Rxvt-unicode uses gobs of memory, how can I reduce that?
- Rxvt-unicode tries to obey the rule of not charging you for
- something you don't use. One thing you should try is to configure
- out all settings that you don't need, for example, Xft support is a
- resource hog by design, when used. Compiling it out ensures that no
- Xft font will be loaded accidentally when rxvt-unicode tries to find
- a font for your characters.
-
- Also, many people (me included) like large windows and even larger
- scrollback buffers: Without "--enable-unicode3", rxvt-unicode will
- use 6 bytes per screen cell. For a 160x?? window this amounts to
- almost a kilobyte per line. A scrollback buffer of 10000 lines will
- then (if full) use 10 Megabytes of memory. With "--enable-unicode3"
- it gets worse, as rxvt-unicode then uses 8 bytes per screen cell.
-
- Can I speed up Xft rendering somehow?
- Yes, the most obvious way to speed it up is to avoid Xft entirely,
- as it is simply slow. If you still want Xft fonts you might try to
- disable antialiasing (by appending ":antialiasing=false"), which
- saves lots of memory and also speeds up rendering considerably.
-
- Rxvt-unicode doesn't seem to anti-alias its fonts, what is wrong?
- Rxvt-unicode will use whatever you specify as a font. If it needs to
- fall back to it's default font search list it will prefer X11 core
- fonts, because they are small and fast, and then use Xft fonts. It
- has antialiasing disabled for most of them, because the author
- thinks they look best that way.
-
- If you want antialiasing, you have to specify the fonts manually.
-
- Mouse cut/paste suddenly no longer works.
- Make sure that mouse reporting is actually turned off since killing
- some editors prematurely may leave the mouse in mouse report mode.
- I've heard that tcsh may use mouse reporting unless it otherwise
- specified. A quick check is to see if cut/paste works when the Alt
- or Shift keys are depressed. See rxvt(7)
-
- What's with this bold/blink stuff?
- If no bold colour is set via "colorBD:", bold will invert text using
- the standard foreground colour.
-
- For the standard background colour, blinking will actually make the
- text blink when compiled with "--enable-blinking". with standard
- colours. Without "--enable-blinking", the blink attribute will be
- ignored.
-
- On ANSI colours, bold/blink attributes are used to set
- high-intensity foreground/background colors.
-
- color0-7 are the low-intensity colors.
-
- color8-15 are the corresponding high-intensity colors.
-
- I don't like the screen colors. How do I change them?
- You can change the screen colors at run-time using ~/.Xdefaults
- resources (or as long-options).
-
- Here are values that are supposed to resemble a VGA screen,
- including the murky brown that passes for low-intensity yellow:
-
- URxvt.color0: #000000
- URxvt.color1: #A80000
- URxvt.color2: #00A800
- URxvt.color3: #A8A800
- URxvt.color4: #0000A8
- URxvt.color5: #A800A8
- URxvt.color6: #00A8A8
- URxvt.color7: #A8A8A8
-
- URxvt.color8: #000054
- URxvt.color9: #FF0054
- URxvt.color10: #00FF54
- URxvt.color11: #FFFF54
- URxvt.color12: #0000FF
- URxvt.color13: #FF00FF
- URxvt.color14: #00FFFF
- URxvt.color15: #FFFFFF
-
- And here is a more complete set of non-standard colors described
- (not by me) as "pretty girly".
-
- URxvt.cursorColor: #dc74d1
- URxvt.pointerColor: #dc74d1
- URxvt.background: #0e0e0e
- URxvt.foreground: #4ad5e1
- URxvt.color0: #000000
- URxvt.color8: #8b8f93
- URxvt.color1: #dc74d1
- URxvt.color9: #dc74d1
- URxvt.color2: #0eb8c7
- URxvt.color10: #0eb8c7
- URxvt.color3: #dfe37e
- URxvt.color11: #dfe37e
- URxvt.color5: #9e88f0
- URxvt.color13: #9e88f0
- URxvt.color6: #73f7ff
- URxvt.color14: #73f7ff
- URxvt.color7: #e1dddd
- URxvt.color15: #e1dddd
-
- How can I start rxvtd in a race-free way?
- Despite it's name, rxvtd is not a real daemon, but more like a
- server that answers rxvtc's requests, so it doesn't background
- itself.
-
- To ensure rxvtd is listening on it's socket, you can use the
- following method to wait for the startup message before continuing:
-
- { rxvtd & } | read
-
- What's with the strange Backspace/Delete key behaviour?
- Assuming that the physical Backspace key corresponds to the
- BackSpace keysym (not likely for Linux ... see the following
- question) there are two standard values that can be used for
- Backspace: "^H" and "^?".
-
- Historically, either value is correct, but rxvt-unicode adopts the
- debian policy of using "^?" when unsure, because it's the one only
- only correct choice :).
-
- Rxvt-unicode tries to inherit the current stty settings and uses the
- value of `erase' to guess the value for backspace. If rxvt-unicode
- wasn't started from a terminal (say, from a menu or by remote
- shell), then the system value of `erase', which corresponds to
- CERASE in <termios.h>, will be used (which may not be the same as
- your stty setting).
-
- For starting a new rxvt-unicode:
-
- # use Backspace = ^H
- $ stty erase ^H
- $ rxvt
-
- # use Backspace = ^?
- $ stty erase ^?
- $ rxvt
-
- Toggle with "ESC [ 36 h" / "ESC [ 36 l" as documented in rxvt(7).
-
- For an existing rxvt-unicode:
-
- # use Backspace = ^H
- $ stty erase ^H
- $ echo -n "^[[36h"
-
- # use Backspace = ^?
- $ stty erase ^?
- $ echo -n "^[[36l"
-
- This helps satisfy some of the Backspace discrepancies that occur,
- but if you use Backspace = "^H", make sure that the termcap/terminfo
- value properly reflects that.
-
- The Delete key is a another casualty of the ill-defined Backspace
- problem. To avoid confusion between the Backspace and Delete keys,
- the Delete key has been assigned an escape sequence to match the
- vt100 for Execute ("ESC [ 3 ~") and is in the supplied
- termcap/terminfo.
-
- Some other Backspace problems:
-
- some editors use termcap/terminfo, some editors (vim I'm told)
- expect Backspace = ^H, GNU Emacs (and Emacs-like editors) use ^H for
- help.
-
- Perhaps someday this will all be resolved in a consistent manner.
-
- I don't like the key-bindings. How do I change them?
- There are some compile-time selections available via configure.
- Unless you have run "configure" with the "--disable-resources"
- option you can use the `keysym' resource to alter the keystrings
- associated with keysyms.
-
- Here's an example for a URxvt session started using "rxvt -name
- URxvt"
-
- URxvt.keysym.Home: \033[1~
- URxvt.keysym.End: \033[4~
- URxvt.keysym.C-apostrophe: \033<C-'>
- URxvt.keysym.C-slash: \033<C-/>
- URxvt.keysym.C-semicolon: \033<C-;>
- URxvt.keysym.C-grave: \033<C-`>
- URxvt.keysym.C-comma: \033<C-,>
- URxvt.keysym.C-period: \033<C-.>
- URxvt.keysym.C-0x60: \033<C-`>
- URxvt.keysym.C-Tab: \033<C-Tab>
- URxvt.keysym.C-Return: \033<C-Return>
- URxvt.keysym.S-Return: \033<S-Return>
- URxvt.keysym.S-space: \033<S-Space>
- URxvt.keysym.M-Up: \033<M-Up>
- URxvt.keysym.M-Down: \033<M-Down>
- URxvt.keysym.M-Left: \033<M-Left>
- URxvt.keysym.M-Right: \033<M-Right>
- URxvt.keysym.M-C-0: list \033<M-C- 0123456789 >
- URxvt.keysym.M-C-a: list \033<M-C- abcdefghijklmnopqrstuvwxyz >
- URxvt.keysym.F12: command:\033]701;zh_CN.GBK\007
-
- See some more examples in the documentation for the keysym resource.
-
- 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 mappings that rxvt-unicode doesn't recognize.
- KP_Insert == Insert
- F22 == Print
- F27 == Home
- F29 == Prior
- F33 == End
- F35 == Next
-
- Rather than have rxvt-unicode try to accommodate all the various
- possible keyboard mappings, it is better to use `xmodmap' to remap
- the keys as required for your particular machine.
-
- How do I distinguish wether I'm running rxvt-unicode or a regular xterm?
- I need this to decide about setting colors etc.
- rxvt and rxvt-unicode always export the variable "COLORTERM", so you
- can check and see if that is set. Note that several programs, JED,
- slrn, Midnight Commander automatically check this variable to decide
- whether or not to use color.
-
- How do I set the correct, full IP address for the DISPLAY variable?
- If you've compiled rxvt-unicode with DISPLAY_IS_IP and have enabled
- insecure mode then it is possible to use the following shell script
- snippets to correctly set the display. If your version of
- rxvt-unicode wasn't also compiled with ESCZ_ANSWER (as assumed in
- these snippets) then the COLORTERM variable can be used to
- distinguish rxvt-unicode from a regular xterm.
-
- Courtesy of Chuck Blake <cblake@BBN.COM> with the following shell
- script snippets:
-
- # Bourne/Korn/POSIX family of shells:
- [ ${TERM:-foo} = foo ] && TERM=xterm # assume an xterm if we don't know
- if [ ${TERM:-foo} = xterm ]; then
- stty -icanon -echo min 0 time 15 # see if enhanced rxvt or not
- echo -n '^[Z'
- read term_id
- stty icanon echo
- if [ ""${term_id} = '^[[?1;2C' -a ${DISPLAY:-foo} = foo ]; then
- echo -n '^[[7n' # query the rxvt we are in for the DISPLAY string
- read DISPLAY # set it in our local shell
- fi
- fi
-
- How do I compile the manual pages for myself?
- You need to have a recent version of perl installed as
- /usr/bin/perl, one that comes with pod2man, pod2text and pod2html.
- Then go to the doc subdirectory and enter "make alldoc".
-
- My question isn't answered here, can I ask a human?
- Before sending me mail, you could go to IRC: "irc.freenode.net",
- channel "#rxvt-unicode" has some rxvt-unicode enthusiasts that might
- be interested in learning about new and exciting problems (but not
- FAQs :).
+RXVT-UNICODE/URXVT FREQUENTLY ASKED QUESTIONS
+ Meta, Features & Commandline Issues
+ My question isn't answered here, can I ask a human?
+ Before sending me mail, you could go to IRC: "irc.freenode.net", channel
+ "#rxvt-unicode" has some rxvt-unicode enthusiasts that might be
+ interested in learning about new and exciting problems (but not FAQs :).
+
+ I use Gentoo, and I have a problem...
+ There are three big problems with Gentoo Linux: first of all, most if
+ not all Gentoo systems are completely broken (missing or mismatched
+ header files, broken compiler etc. are just the tip of the iceberg);
+ secondly, the Gentoo maintainer thinks it is a good idea to add broken
+ patches to the code; and lastly, it should be called Gentoo GNU/Linux.
+
+ For these reasons, it is impossible to support rxvt-unicode on Gentoo.
+ Problems appearing on Gentoo systems will usually simply be ignored
+ unless they can be reproduced on non-Gentoo systems.
+
+ Does it support tabs, can I have a tabbed rxvt-unicode?
+ Beginning with version 7.3, there is a perl extension that implements a
+ simple tabbed terminal. It is installed by default, so any of these
+ should give you tabs:
+
+ urxvt -pe tabbed
+
+ URxvt.perl-ext-common: default,tabbed
+
+ It will also work fine with tabbing functionality of many window
+ managers or similar tabbing programs, and its embedding-features allow
+ it to be embedded into other programs, as witnessed by doc/rxvt-tabbed
+ or the upcoming "Gtk2::URxvt" perl module, which features a tabbed urxvt
+ (murxvt) terminal as an example embedding application.
+
+ How do I know which rxvt-unicode version I'm using?
+ The version number is displayed with the usage (-h). Also the escape
+ sequence "ESC [ 8 n" sets the window title to the version number. When
+ using the urxvtc client, the version displayed is that of the daemon.
+
+ Rxvt-unicode uses gobs of memory, how can I reduce that?
+ Rxvt-unicode tries to obey the rule of not charging you for something
+ you don't use. One thing you should try is to configure out all settings
+ that you don't need, for example, Xft support is a resource hog by
+ design, when used. Compiling it out ensures that no Xft font will be
+ loaded accidentally when rxvt-unicode tries to find a font for your
+ characters.
+
+ Also, many people (me included) like large windows and even larger
+ scrollback buffers: Without "--enable-unicode3", rxvt-unicode will use 6
+ bytes per screen cell. For a 160x?? window this amounts to almost a
+ kilobyte per line. A scrollback buffer of 10000 lines will then (if
+ full) use 10 Megabytes of memory. With "--enable-unicode3" it gets
+ worse, as rxvt-unicode then uses 8 bytes per screen cell.
+
+ How can I start urxvtd in a race-free way?
+ Try "urxvtd -f -o", which tells urxvtd to open the display, create the
+ listening socket and then fork.
+
+ How can I start urxvtd automatically when I run urxvtc?
+ If you want to start urxvtd automatically whenever you run urxvtc and
+ the daemon isn't running yet, use this script:
+
+ #!/bin/sh
+ urxvtc "$@"
+ if [ $? -eq 2 ]; then
+ urxvtd -q -o -f
+ urxvtc "$@"
+ fi
+
+ This tries to create a new terminal, and if fails with exit status 2,
+ meaning it couldn't connect to the daemon, it will start the daemon and
+ re-run the command. Subsequent invocations of the script will re-use the
+ existing daemon.
+
+ How do I distinguish whether I'm running rxvt-unicode or a regular xterm? I need this to decide about setting colors etc.
+ The original rxvt and rxvt-unicode always export the variable
+ "COLORTERM", so you can check and see if that is set. Note that several
+ programs, JED, slrn, Midnight Commander automatically check this
+ variable to decide whether or not to use color.
+
+ How do I set the correct, full IP address for the DISPLAY variable?
+ If you've compiled rxvt-unicode with DISPLAY_IS_IP and have enabled
+ insecure mode then it is possible to use the following shell script
+ snippets to correctly set the display. If your version of rxvt-unicode
+ wasn't also compiled with ESCZ_ANSWER (as assumed in these snippets)
+ then the COLORTERM variable can be used to distinguish rxvt-unicode from
+ a regular xterm.
+
+ Courtesy of Chuck Blake <cblake@BBN.COM> with the following shell script
+ snippets:
+
+ # Bourne/Korn/POSIX family of shells:
+ [ ${TERM:-foo} = foo ] && TERM=xterm # assume an xterm if we don't know
+ if [ ${TERM:-foo} = xterm ]; then
+ stty -icanon -echo min 0 time 15 # see if enhanced rxvt or not
+ echo -n '^[Z'
+ read term_id
+ stty icanon echo
+ if [ ""${term_id} = '^[[?1;2C' -a ${DISPLAY:-foo} = foo ]; then
+ echo -n '^[[7n' # query the rxvt we are in for the DISPLAY string
+ read DISPLAY # set it in our local shell
+ fi
+ fi
+
+ How do I compile the manual pages on my own?
+ You need to have a recent version of perl installed as /usr/bin/perl,
+ one that comes with pod2man, pod2text and pod2xhtml (from Pod::Xhtml).
+ Then go to the doc subdirectory and enter "make alldoc".
+
+ Isn't rxvt-unicode supposed to be small? Don't all those features bloat?
+ I often get asked about this, and I think, no, they didn't cause extra
+ bloat. If you compare a minimal rxvt and a minimal urxvt, you can see
+ that the urxvt binary is larger (due to some encoding tables always
+ being compiled in), but it actually uses less memory (RSS) after
+ startup. Even with "--disable-everything", this comparison is a bit
+ unfair, as many features unique to urxvt (locale, encoding conversion,
+ iso14755 etc.) are already in use in this mode.
+
+ text data bss drs rss filename
+ 98398 1664 24 15695 1824 rxvt --disable-everything
+ 188985 9048 66616 18222 1788 urxvt --disable-everything
+
+ When you "--enable-everything" (which *is* unfair, as this involves xft
+ and full locale/XIM support which are quite bloaty inside libX11 and my
+ libc), the two diverge, but not unreasonably so.
+
+ text data bss drs rss filename
+ 163431 2152 24 20123 2060 rxvt --enable-everything
+ 1035683 49680 66648 29096 3680 urxvt --enable-everything
+
+ The very large size of the text section is explained by the east-asian
+ encoding tables, which, if unused, take up disk space but nothing else
+ and can be compiled out unless you rely on X11 core fonts that use those
+ encodings. The BSS size comes from the 64k emergency buffer that my c++
+ compiler allocates (but of course doesn't use unless you are out of
+ memory). Also, using an xft font instead of a core font immediately adds
+ a few megabytes of RSS. Xft indeed is responsible for a lot of RSS even
+ when not used.
+
+ Of course, due to every character using two or four bytes instead of
+ one, a large scrollback buffer will ultimately make rxvt-unicode use
+ more memory.
+
+ Compared to e.g. Eterm (5112k), aterm (3132k) and xterm (4680k), this
+ still fares rather well. And compared to some monsters like
+ gnome-terminal (21152k + extra 4204k in separate processes) or konsole
+ (22200k + extra 43180k in daemons that stay around after exit, plus half
+ a minute of startup time, including the hundreds of warnings it spits
+ out), it fares extremely well *g*.
+
+ Why C++, isn't that unportable/bloated/uncool?
+ Is this a question? :) It comes up very often. The simple answer is: I
+ had to write it, and C++ allowed me to write and maintain it in a
+ fraction of the time and effort (which is a scarce resource for me). Put
+ even shorter: It simply wouldn't exist without C++.
+
+ My personal stance on this is that C++ is less portable than C, but in
+ the case of rxvt-unicode this hardly matters, as its portability limits
+ are defined by things like X11, pseudo terminals, locale support and
+ unix domain sockets, which are all less portable than C++ itself.
+
+ Regarding the bloat, see the above question: It's easy to write programs
+ in C that use gobs of memory, an certainly possible to write programs in
+ C++ that don't. C++ also often comes with large libraries, but this is
+ not necessarily the case with GCC. Here is what rxvt links against on my
+ system with a minimal config:
+
+ libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
+ libc.so.6 => /lib/libc.so.6 (0x00002aaaaadde000)
+ libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab01d000)
+ /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
+
+ And here is rxvt-unicode:
+
+ libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000)
+ libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00002aaaaada2000)
+ libc.so.6 => /lib/libc.so.6 (0x00002aaaaaeb0000)
+ libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab0ee000)
+ /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000)
+
+ No large bloated libraries (of course, none were linked in statically),
+ except maybe libX11 :)
+
+ Rendering, Font & Look and Feel Issues
+ I can't get transparency working, what am I doing wrong?
+ First of all, please address all transparency related issues to Sasha
+ Vasko at sasha@aftercode.net and do not bug the author about it. Also,
+ if you can't get it working consider it a rite of passage: ... and you
+ failed.
+
+ Here are four ways to get transparency. Do read the manpage and option
+ descriptions for the programs mentioned and rxvt-unicode. Really, do it!
+
+ 1. Use transparent mode:
+
+ Esetroot wallpaper.jpg
+ urxvt -tr -tint red -sh 40
+
+ That works. If you think it doesn't, you lack transparency and tinting
+ support, or you are unable to read.
+
+ 2. Use a simple pixmap and emulate pseudo-transparency. This enables you
+ to use effects other than tinting and shading: Just shade/tint/whatever
+ your picture with gimp or any other tool:
+
+ convert wallpaper.jpg -blur 20x20 -modulate 30 background.jpg
+ urxvt -pixmap "background.jpg;:root"
+
+ That works. If you think it doesn't, you lack AfterImage support, or you
+ are unable to read.
+
+ 3. Use an ARGB visual:
+
+ urxvt -depth 32 -fg grey90 -bg rgba:0000/0000/4444/cccc
+
+ This requires XFT support, and the support of your X-server. If that
+ doesn't work for you, blame Xorg and Keith Packard. ARGB visuals aren't
+ there yet, no matter what they claim. Rxvt-Unicode contains the
+ necessary bugfixes and workarounds for Xft and Xlib to make it work, but
+ that doesn't mean that your WM has the required kludges in place.
+
+ 4. Use xcompmgr and let it do the job:
+
+ xprop -frame -f _NET_WM_WINDOW_OPACITY 32c \
+ -set _NET_WM_WINDOW_OPACITY 0xc0000000
+
+ Then click on a window you want to make transparent. Replace 0xc0000000
+ by other values to change the degree of opacity. If it doesn't work and
+ your server crashes, you got to keep the pieces.
+
+ Why does rxvt-unicode sometimes leave pixel droppings?
+ Most fonts were not designed for terminal use, which means that
+ character size varies a lot. A font that is otherwise fine for terminal
+ use might contain some characters that are simply too wide. Rxvt-unicode
+ will avoid these characters. For characters that are just "a bit" too
+ wide a special "careful" rendering mode is used that redraws adjacent
+ characters.
+
+ All of this requires that fonts do not lie about character sizes,
+ however: Xft fonts often draw glyphs larger than their acclaimed
+ bounding box, and rxvt-unicode has no way of detecting this (the correct
+ way is to ask for the character bounding box, which unfortunately is
+ wrong in these cases).
+
+ It's not clear (to me at least), whether this is a bug in Xft, freetype,
+ or the respective font. If you encounter this problem you might try
+ using the "-lsp" option to give the font more height. If that doesn't
+ work, you might be forced to use a different font.
+
+ All of this is not a problem when using X11 core fonts, as their
+ bounding box data is correct.
+
+ How can I keep rxvt-unicode from using reverse video so much?
+ First of all, make sure you are running with the right terminal settings
+ ("TERM=rxvt-unicode"), which will get rid of most of these effects. Then
+ make sure you have specified colours for italic and bold, as otherwise
+ rxvt-unicode might use reverse video to simulate the effect:
+
+ URxvt.colorBD: white
+ URxvt.colorIT: green
+
+ Some programs assume totally weird colours (red instead of blue), how can I fix that?
+ For some unexplainable reason, some rare programs assume a very weird
+ colour palette when confronted with a terminal with more than the
+ standard 8 colours (rxvt-unicode supports 88). The right fix is, of
+ course, to fix these programs not to assume non-ISO colours without very
+ good reasons.
+
+ In the meantime, you can either edit your "rxvt-unicode" terminfo
+ definition to only claim 8 colour support or use "TERM=rxvt", which will
+ fix colours but keep you from using other rxvt-unicode features.
+
+ Can I switch the fonts at runtime?
+ Yes, using an escape sequence. Try something like this, which has the
+ same effect as using the "-fn" switch, and takes effect immediately:
+
+ printf '\33]50;%s\007' "9x15bold,xft:Kochi Gothic"
+
+ This is useful if you e.g. work primarily with japanese (and prefer a
+ japanese font), but you have to switch to chinese temporarily, where
+ japanese fonts would only be in your way.
+
+ You can think of this as a kind of manual ISO-2022 switching.
+
+ Why do italic characters look as if clipped?
+ Many fonts have difficulties with italic characters and hinting. For
+ example, the otherwise very nicely hinted font "xft:Bitstream Vera Sans
+ Mono" completely fails in its italic face. A workaround might be to
+ enable freetype autohinting, i.e. like this:
+
+ URxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
+ URxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
+
+ Can I speed up Xft rendering somehow?
+ Yes, the most obvious way to speed it up is to avoid Xft entirely, as it
+ is simply slow. If you still want Xft fonts you might try to disable
+ antialiasing (by appending ":antialias=false"), which saves lots of
+ memory and also speeds up rendering considerably.
+
+ Rxvt-unicode doesn't seem to anti-alias its fonts, what is wrong?
+ Rxvt-unicode will use whatever you specify as a font. If it needs to
+ fall back to its default font search list it will prefer X11 core fonts,
+ because they are small and fast, and then use Xft fonts. It has
+ antialiasing disabled for most of them, because the author thinks they
+ look best that way.
+
+ If you want antialiasing, you have to specify the fonts manually.
+
+ What's with this bold/blink stuff?
+ If no bold colour is set via "colorBD:", bold will invert text using the
+ standard foreground colour.
+
+ For the standard background colour, blinking will actually make the text
+ blink when compiled with "--enable-text-blink". Without
+ "--enable-text-blink", the blink attribute will be ignored.
+
+ On ANSI colours, bold/blink attributes are used to set high-intensity
+ foreground/background colors.
+
+ color0-7 are the low-intensity colors.
+
+ color8-15 are the corresponding high-intensity colors.
+
+ I don't like the screen colors. How do I change them?
+ You can change the screen colors at run-time using ~/.Xdefaults
+ resources (or as long-options).
+
+ Here are values that are supposed to resemble a VGA screen, including
+ the murky brown that passes for low-intensity yellow:
+
+ URxvt.color0: #000000
+ URxvt.color1: #A80000
+ URxvt.color2: #00A800
+ URxvt.color3: #A8A800
+ URxvt.color4: #0000A8
+ URxvt.color5: #A800A8
+ URxvt.color6: #00A8A8
+ URxvt.color7: #A8A8A8
+
+ URxvt.color8: #000054
+ URxvt.color9: #FF0054
+ URxvt.color10: #00FF54
+ URxvt.color11: #FFFF54
+ URxvt.color12: #0000FF
+ URxvt.color13: #FF00FF
+ URxvt.color14: #00FFFF
+ URxvt.color15: #FFFFFF
+
+ And here is a more complete set of non-standard colors.
+
+ URxvt.cursorColor: #dc74d1
+ URxvt.pointerColor: #dc74d1
+ URxvt.background: #0e0e0e
+ URxvt.foreground: #4ad5e1
+ URxvt.color0: #000000
+ URxvt.color8: #8b8f93
+ URxvt.color1: #dc74d1
+ URxvt.color9: #dc74d1
+ URxvt.color2: #0eb8c7
+ URxvt.color10: #0eb8c7
+ URxvt.color3: #dfe37e
+ URxvt.color11: #dfe37e
+ URxvt.color5: #9e88f0
+ URxvt.color13: #9e88f0
+ URxvt.color6: #73f7ff
+ URxvt.color14: #73f7ff
+ URxvt.color7: #e1dddd
+ URxvt.color15: #e1dddd
+
+ They have been described (not by me) as "pretty girly".
+
+ Why do some characters look so much different than others?
+ See next entry.
+
+ How does rxvt-unicode choose fonts?
+ Most fonts do not contain the full range of Unicode, which is fine.
+ Chances are that the font you (or the admin/package maintainer of your
+ system/os) have specified does not cover all the characters you want to
+ display.
+
+ rxvt-unicode makes a best-effort try at finding a replacement font.
+ Often the result is fine, but sometimes the chosen font looks
+ bad/ugly/wrong. Some fonts have totally strange characters that don't
+ resemble the correct glyph at all, and rxvt-unicode lacks the artificial
+ intelligence to detect that a specific glyph is wrong: it has to believe
+ the font that the characters it claims to contain indeed look correct.
+
+ In that case, select a font of your taste and add it to the font list,
+ e.g.:
+
+ urxvt -fn basefont,font2,font3...
+
+ When rxvt-unicode sees a character, it will first look at the base font.
+ If the base font does not contain the character, it will go to the next
+ font, and so on. Specifying your own fonts will also speed up this
+ search and use less resources within rxvt-unicode and the X-server.
+
+ The only limitation is that none of the fonts may be larger than the
+ base font, as the base font defines the terminal character cell size,
+ which must be the same due to the way terminals work.
+
+ Why do some chinese characters look so different than others?
+ This is because there is a difference between script and language --
+ rxvt-unicode does not know which language the text that is output is, as
+ it only knows the unicode character codes. If rxvt-unicode first sees a
+ japanese/chinese character, it might choose a japanese font for display.
+ Subsequent japanese characters will use that font. Now, many chinese
+ characters aren't represented in japanese fonts, so when the first
+ non-japanese character comes up, rxvt-unicode will look for a chinese
+ font -- unfortunately at this point, it will still use the japanese font
+ for chinese characters that are also in the japanese font.
+
+ The workaround is easy: just tag a chinese font at the end of your font
+ list (see the previous question). The key is to view the font list as a
+ preference list: If you expect more japanese, list a japanese font
+ first. If you expect more chinese, put a chinese font first.
+
+ In the future it might be possible to switch language preferences at
+ runtime (the internal data structure has no problem with using different
+ fonts for the same character at the same time, but no interface for this
+ has been designed yet).
+
+ Until then, you might get away with switching fonts at runtime (see "Can
+ I switch the fonts at runtime?" later in this document).
+
+ How can I make mplayer display video correctly?
+ We are working on it, in the meantime, as a workaround, use something
+ like:
+
+ urxvt -b 600 -geometry 20x1 -e sh -c 'mplayer -wid $WINDOWID file...'
+
+ Keyboard, Mouse & User Interaction
+ The new selection selects pieces that are too big, how can I select single words?
+ If you want to select e.g. alphanumeric words, you can use the following
+ setting:
+
+ URxvt.selection.pattern-0: ([[:word:]]+)
+
+ If you click more than twice, the selection will be extended more and
+ more.
+
+ To get a selection that is very similar to the old code, try this
+ pattern:
+
+ URxvt.selection.pattern-0: ([^"&'()*,;<=>?@[\\\\]^`{|})]+)
+
+ Please also note that the *LeftClick Shift-LeftClick* combination also
+ selects words like the old code.
+
+ I don't like the new selection/popups/hotkeys/perl, how do I change/disable it?
+ You can disable the perl extension completely by setting the
+ perl-ext-common resource to the empty string, which also keeps
+ rxvt-unicode from initialising perl, saving memory.
+
+ If you only want to disable specific features, you first have to
+ identify which perl extension is responsible. For this, read the section
+ PREPACKAGED EXTENSIONS in the urxvtperl(3) manpage. For example, to
+ disable the selection-popup and option-popup, specify this
+ perl-ext-common resource:
+
+ URxvt.perl-ext-common: default,-selection-popup,-option-popup
+
+ This will keep the default extensions, but disable the two popup
+ extensions. Some extensions can also be configured, for example,
+ scrollback search mode is triggered by M-s. You can move it to any other
+ combination either by setting the searchable-scrollback resource:
+
+ URxvt.searchable-scrollback: CM-s
+
+ The cursor moves when selecting text in the current input line, how do I switch this off?
+ See next entry.
+
+ During rlogin/ssh/telnet/etc. sessions, clicking near the cursor outputs strange escape sequences, how do I fix this?
+ These are caused by the "readline" perl extension. Under normal
+ circumstances, it will move your cursor around when you click into the
+ line that contains it. It tries hard not to do this at the wrong moment,
+ but when running a program that doesn't parse cursor movements or in
+ some cases during rlogin sessions, it fails to detect this properly.
+
+ You can permanently switch this feature off by disabling the "readline"
+ extension:
+
+ URxvt.perl-ext-common: default,-readline
+
+ My numerical keypad acts weird and generates differing output?
+ Some Debian GNUL/Linux users seem to have this problem, although no
+ specific details were reported so far. It is possible that this is
+ caused by the wrong "TERM" setting, although the details of whether and
+ how this can happen are unknown, as "TERM=rxvt" should offer a
+ compatible keymap. See the answer to the previous question, and please
+ report if that helped.
+
+ My Compose (Multi_key) key is no longer working.
+ The most common causes for this are that either your locale is not set
+ correctly, or you specified a preeditStyle that is not supported by your
+ input method. For example, if you specified OverTheSpot and your input
+ method (e.g. the default input method handling Compose keys) does not
+ support this (for instance because it is not visual), then rxvt-unicode
+ will continue without an input method.
+
+ In this case either do not specify a preeditStyle or specify more than
+ one pre-edit style, such as OverTheSpot,Root,None.
+
+ If it still doesn't work, then maybe your input method doesn't support
+ compose sequences - to fall back to the built-in one, make sure you
+ don't specify an input method via "-im" or "XMODIFIERS".
+
+ I cannot type "Ctrl-Shift-2" to get an ASCII NUL character due to ISO 14755
+ Either try "Ctrl-2" alone (it often is mapped to ASCII NUL even on
+ international keyboards) or simply use ISO 14755 support to your
+ advantage, typing <Ctrl-Shift-0> to get a ASCII NUL. This works for
+ other codes, too, such as "Ctrl-Shift-1-d" to type the default telnet
+ escape character and so on.
+
+ Mouse cut/paste suddenly no longer works.
+ Make sure that mouse reporting is actually turned off since killing some
+ editors prematurely may leave the mouse in mouse report mode. I've heard
+ that tcsh may use mouse reporting unless it otherwise specified. A quick
+ check is to see if cut/paste works when the Alt or Shift keys are
+ depressed.
+
+ What's with the strange Backspace/Delete key behaviour?
+ Assuming that the physical Backspace key corresponds to the Backspace
+ keysym (not likely for Linux ... see the following question) there are
+ two standard values that can be used for Backspace: "^H" and "^?".
+
+ Historically, either value is correct, but rxvt-unicode adopts the
+ debian policy of using "^?" when unsure, because it's the one and only
+ correct choice :).
+
+ Rxvt-unicode tries to inherit the current stty settings and uses the
+ value of `erase' to guess the value for backspace. If rxvt-unicode
+ wasn't started from a terminal (say, from a menu or by remote shell),
+ then the system value of `erase', which corresponds to CERASE in
+ <termios.h>, will be used (which may not be the same as your stty
+ setting).
+
+ For starting a new rxvt-unicode:
+
+ # use Backspace = ^H
+ $ stty erase ^H
+ $ urxvt
+
+ # use Backspace = ^?
+ $ stty erase ^?
+ $ urxvt
+
+ Toggle with "ESC [ 36 h" / "ESC [ 36 l".
+
+ For an existing rxvt-unicode:
+
+ # use Backspace = ^H
+ $ stty erase ^H
+ $ echo -n "^[[36h"
+
+ # use Backspace = ^?
+ $ stty erase ^?
+ $ echo -n "^[[36l"
+
+ This helps satisfy some of the Backspace discrepancies that occur, but
+ if you use Backspace = "^H", make sure that the termcap/terminfo value
+ properly reflects that.
+
+ The Delete key is a another casualty of the ill-defined Backspace
+ problem. To avoid confusion between the Backspace and Delete keys, the
+ Delete key has been assigned an escape sequence to match the vt100 for
+ Execute ("ESC [ 3 ~") and is in the supplied termcap/terminfo.
+
+ Some other Backspace problems:
+
+ some editors use termcap/terminfo, some editors (vim I'm told) expect
+ Backspace = ^H, GNU Emacs (and Emacs-like editors) use ^H for help.
+
+ Perhaps someday this will all be resolved in a consistent manner.
+
+ I don't like the key-bindings. How do I change them?
+ There are some compile-time selections available via configure. Unless
+ you have run "configure" with the "--disable-resources" option you can
+ use the `keysym' resource to alter the keystrings associated with
+ keysyms.
+
+ Here's an example for a URxvt session started using "urxvt -name URxvt"
+
+ URxvt.keysym.Home: \033[1~
+ URxvt.keysym.End: \033[4~
+ URxvt.keysym.C-apostrophe: \033<C-'>
+ URxvt.keysym.C-slash: \033<C-/>
+ URxvt.keysym.C-semicolon: \033<C-;>
+ URxvt.keysym.C-grave: \033<C-`>
+ URxvt.keysym.C-comma: \033<C-,>
+ URxvt.keysym.C-period: \033<C-.>
+ URxvt.keysym.C-0x60: \033<C-`>
+ URxvt.keysym.C-Tab: \033<C-Tab>
+ URxvt.keysym.C-Return: \033<C-Return>
+ URxvt.keysym.S-Return: \033<S-Return>
+ URxvt.keysym.S-space: \033<S-Space>
+ URxvt.keysym.M-Up: \033<M-Up>
+ URxvt.keysym.M-Down: \033<M-Down>
+ URxvt.keysym.M-Left: \033<M-Left>
+ URxvt.keysym.M-Right: \033<M-Right>
+ URxvt.keysym.M-C-0: list \033<M-C- 0123456789 >
+ URxvt.keysym.M-C-a: list \033<M-C- abcdefghijklmnopqrstuvwxyz >
+ URxvt.keysym.F12: command:\033]701;zh_CN.GBK\007
+
+ See some more examples in the documentation for the keysym resource.
+
+ 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
+ KP_Insert == Insert
+ F22 == Print
+ F27 == Home
+ F29 == Prior
+ F33 == End
+ F35 == Next
+
+ Rather than have rxvt-unicode try to accommodate all the various
+ possible keyboard mappings, it is better to use `xmodmap' to remap the
+ keys as required for your particular machine.
+
+ Terminal Configuration
+ Can I see a typical configuration?
+ The default configuration tries to be xterm-like, which I don't like
+ that much, but it's least surprise to regular users.
+
+ As a rxvt or rxvt-unicode user, you are practically supposed to invest
+ time into customising your terminal. To get you started, here is the
+ author's .Xdefaults entries, with comments on what they do. It's
+ certainly not *typical*, but what's typical...
+
+ URxvt.cutchars: "()*,<>[]{}|'
+ URxvt.print-pipe: cat >/tmp/xxx
+
+ These are just for testing stuff.
+
+ URxvt.imLocale: ja_JP.UTF-8
+ URxvt.preeditType: OnTheSpot,None
+
+ This tells rxvt-unicode to use a special locale when communicating with
+ the X Input Method, and also tells it to only use the OnTheSpot pre-edit
+ type, which requires the "xim-onthespot" perl extension but rewards me
+ with correct-looking fonts.
+
+ URxvt.perl-lib: /root/lib/urxvt
+ URxvt.perl-ext-common: default,selection-autotransform,selection-pastebin,xim-onthespot,remote-clipboard
+ URxvt.selection.pattern-0: ( at .*? line \\d+)
+ URxvt.selection.pattern-1: ^(/[^:]+):\
+ URxvt.selection-autotransform.0: s/^([^:[:space:]]+):(\\d+):?$/:e \\Q$1\\E\\x0d:$2\\x0d/
+ URxvt.selection-autotransform.1: s/^ at (.*?) line (\\d+)$/:e \\Q$1\\E\\x0d:$2\\x0d/
+
+ This is my perl configuration. The first two set the perl library
+ directory and also tells urxvt to use a large number of extensions. I
+ develop for myself mostly, so I actually use most of the extensions I
+ write.
+
+ The selection stuff mainly makes the selection perl-error-message aware
+ and tells it to convert perl error messages into vi-commands to load the
+ relevant file and go tot he error line number.
+
+ URxvt.scrollstyle: plain
+ URxvt.secondaryScroll: true
+
+ As the documentation says: plain is the preferred scrollbar for the
+ author. The "secondaryScroll" configures urxvt to scroll in full-screen
+ apps, like screen, so lines scrolled out of screen end up in urxvt's
+ scrollback buffer.
+
+ URxvt.background: #000000
+ URxvt.foreground: gray90
+ URxvt.color7: gray90
+ URxvt.colorBD: #ffffff
+ URxvt.cursorColor: #e0e080
+ URxvt.throughColor: #8080f0
+ URxvt.highlightColor: #f0f0f0
+
+ Some colours. Not sure which ones are being used or even non-defaults,
+ but these are in my .Xdefaults. Most notably, they set
+ foreground/background to light gray/black, and also make sure that the
+ colour 7 matches the default foreground colour.
+
+ URxvt.underlineColor: yellow
+
+ Another colour, makes underline lines look different. Sometimes hurts,
+ but is mostly a nice effect.
+
+ URxvt.geometry: 154x36
+ URxvt.loginShell: false
+ URxvt.meta: ignore
+ URxvt.utmpInhibit: true
+
+ Uh, well, should be mostly self-explanatory. By specifying some defaults
+ manually, I can quickly switch them for testing.
+
+ URxvt.saveLines: 8192
+
+ A large scrollback buffer is essential. Really.
+
+ URxvt.mapAlert: true
+
+ The only case I use it is for my IRC window, which I like to keep
+ iconified till people msg me (which beeps).
+
+ URxvt.visualBell: true
+
+ The audible bell is often annoying, especially when in a crowd.
+
+ URxvt.insecure: true
+
+ Please don't hack my mutt! Ooops...
+
+ URxvt.pastableTabs: false
+
+ I once thought this is a great idea.
+
+ urxvt.font: 9x15bold,\
+ -misc-fixed-bold-r-normal--15-140-75-75-c-90-iso10646-1,\
+ -misc-fixed-medium-r-normal--15-140-75-75-c-90-iso10646-1, \
+ [codeset=JISX0208]xft:Kochi Gothic, \
+ xft:Bitstream Vera Sans Mono:autohint=true, \
+ xft:Code2000:antialias=false
+ urxvt.boldFont: -xos4-terminus-bold-r-normal--14-140-72-72-c-80-iso8859-15
+ urxvt.italicFont: xft:Bitstream Vera Sans Mono:italic:autohint=true
+ urxvt.boldItalicFont: xft:Bitstream Vera Sans Mono:bold:italic:autohint=true
+
+ I wrote rxvt-unicode to be able to specify fonts exactly. So don't be
+ overwhelmed. A special note: the "9x15bold" mentioned above is actually
+ the version from XFree-3.3, as XFree-4 replaced it by a totally
+ different font (different glyphs for ";" and many other harmless
+ characters), while the second font is actually the "9x15bold" from
+ XFree4/XOrg. The bold version has less chars than the medium version, so
+ I use it for rare characters, too. When editing sources with vim, I use
+ italic for comments and other stuff, which looks quite good with
+ Bitstream Vera anti-aliased.
+
+ Terminus is a quite bad font (many very wrong glyphs), but for most of
+ my purposes, it works, and gives a different look, as my normal
+ (Non-bold) font is already bold, and I want to see a difference between
+ bold and normal fonts.
+
+ Please note that I used the "urxvt" instance name and not the "URxvt"
+ class name. Thats because I use different configs for different
+ purposes, for example, my IRC window is started with "-name IRC", and
+ uses these defaults:
+
+ IRC*title: IRC
+ IRC*geometry: 87x12+535+542
+ IRC*saveLines: 0
+ IRC*mapAlert: true
+ IRC*font: suxuseuro
+ IRC*boldFont: suxuseuro
+ IRC*colorBD: white
+ IRC*keysym.M-C-1: command:\033]710;suxuseuro\007\033]711;suxuseuro\007
+ IRC*keysym.M-C-2: command:\033]710;9x15bold\007\033]711;9x15bold\007
+
+ "Alt-Ctrl-1" and "Alt-Ctrl-2" switch between two different font sizes.
+ "suxuseuro" allows me to keep an eye (and actually read) stuff while
+ keeping a very small window. If somebody pastes something complicated
+ (e.g. japanese), I temporarily switch to a larger font.
+
+ The above is all in my ".Xdefaults" (I don't use ".Xresources" nor
+ "xrdb"). I also have some resources in a separate ".Xdefaults-hostname"
+ file for different hosts, for example, on ym main desktop, I use:
+
+ URxvt.keysym.C-M-q: command:\033[3;5;5t
+ URxvt.keysym.C-M-y: command:\033[3;5;606t
+ URxvt.keysym.C-M-e: command:\033[3;1605;5t
+ URxvt.keysym.C-M-c: command:\033[3;1605;606t
+ URxvt.keysym.C-M-p: perl:test
+
+ The first for keysym definitions allow me to quickly bring some windows
+ in the layout I like most. Ion users might start laughing but will stop
+ immediately when I tell them that I use my own Fvwm2 module for much the
+ same effect as Ion provides, and I only very rarely use the above key
+ combinations :->
+
+ Why doesn't rxvt-unicode read my resources?
+ Well, why, indeed? It does, in a way very similar to other X
+ applications. Most importantly, this means that if you or your OS loads
+ resources into the X display (the right way to do it), rxvt-unicode will
+ ignore any resource files in your home directory. It will only read
+ $HOME/.Xdefaults when no resources are attached to the display.
+
+ If you have or use an $HOME/.Xresources file, chances are that resources
+ are loaded into your X-server. In this case, you have to re-login after
+ every change (or run xrdb -merge $HOME/.Xresources).
+
+ Also consider the form resources have to use:
+
+ URxvt.resource: value
+
+ If you want to use another form (there are lots of different ways of
+ specifying resources), make sure you understand whether and why it
+ works. If unsure, use the form above.
+
+ When I log-in to another system it tells me about missing terminfo data?
+ The terminal description used by rxvt-unicode is not as widely available
+ as that for xterm, or even rxvt (for which the same problem often
+ arises).
+
+ The correct solution for this problem is to install the terminfo, this
+ can be done by simply installing rxvt-unicode on the remote system as
+ well (in case you have a nice package manager ready), or you can install
+ the terminfo database manually like this (with ncurses infocmp. works as
+ user and root):
+
+ REMOTE=remotesystem.domain
+ infocmp rxvt-unicode | ssh $REMOTE "mkdir -p .terminfo && cat >/tmp/ti && tic /tmp/ti"
+
+ One some systems you might need to set $TERMINFO to the full path of
+ $HOME/.terminfo for this to work.
+
+ If you cannot or do not want to do this, then you can simply set
+ "TERM=rxvt" or even "TERM=xterm", and live with the small number of
+ problems arising, which includes wrong keymapping, less and different
+ colours and some refresh errors in fullscreen applications. It's a nice
+ quick-and-dirty workaround for rare cases, though.
+
+ If you always want to do this (and are fine with the consequences) you
+ can either recompile rxvt-unicode with the desired TERM value or use a
+ resource to set it:
+
+ URxvt.termName: rxvt
+
+ If you don't plan to use rxvt (quite common...) you could also replace
+ the rxvt terminfo file with the rxvt-unicode one and use "TERM=rxvt".
+
+ nano fails with "Error opening terminal: rxvt-unicode"
+ This exceptionally confusing and useless error message is printed by
+ nano when it can't find the terminfo database. Nothing is wrong with
+ your terminal, read the previous answer for a solution.
+
+ "tic" outputs some error when compiling the terminfo entry.
+ Most likely it's the empty definition for "enacs=". Just replace it by
+ "enacs=\E[0@" and try again.
+
+ "bash"'s readline does not work correctly under urxvt.
+ See next entry.
+
+ I need a termcap file entry.
+ One reason you might want this is that some distributions or operating
+ systems still compile some programs using the long-obsoleted termcap
+ library (Fedora Core's bash is one example) and rely on a termcap entry
+ for "rxvt-unicode".
+
+ You could use rxvt's termcap entry with reasonable results in many
+ cases. You can also create a termcap entry by using terminfo's infocmp
+ program like this:
+
+ infocmp -C rxvt-unicode
+
+ Or you could use the termcap entry in doc/etc/rxvt-unicode.termcap,
+ generated by the command above.
+
+ Why does "ls" no longer have coloured output?
+ The "ls" in the GNU coreutils unfortunately doesn't use terminfo to
+ decide whether a terminal has colour, but uses its own configuration
+ file. Needless to say, "rxvt-unicode" is not in its default file (among
+ with most other terminals supporting colour). Either add:
+
+ TERM rxvt-unicode
+
+ to "/etc/DIR_COLORS" or simply add:
+
+ alias ls='ls --color=auto'
+
+ to your ".profile" or ".bashrc".
+
+ Why doesn't vim/emacs etc. use the 88 colour mode?
+ See next entry.
+
+ Why doesn't vim/emacs etc. make use of italic?
+ See next entry.
+
+ Why are the secondary screen-related options not working properly?
+ Make sure you are using "TERM=rxvt-unicode". Some pre-packaged
+ distributions (most notably Debian GNU/Linux) break rxvt-unicode by
+ setting "TERM" to "rxvt", which doesn't have these extra features.
+ Unfortunately, some of these (most notably, again, Debian GNU/Linux)
+ furthermore fail to even install the "rxvt-unicode" terminfo file, so
+ you will need to install it on your own (See the question When I log-in
+ to another system it tells me about missing terminfo data? on how to do
+ this).
+
+ Encoding / Locale / Input Method Issues
+ Rxvt-unicode does not seem to understand the selected encoding?
+ See next entry.
+
+ Unicode does not seem to work?
+ If you encounter strange problems like typing an accented character but
+ getting two unrelated other characters or similar, or if program output
+ is subtly garbled, then you should check your locale settings.
+
+ Rxvt-unicode must be started with the same "LC_CTYPE" setting as the
+ programs running in it. Often rxvt-unicode is started in the "C" locale,
+ while the login script running within the rxvt-unicode window changes
+ the locale to something else, e.g. "en_GB.UTF-8". Needless to say, this
+ is not going to work, and is the most common cause for problems.
+
+ The best thing is to fix your startup environment, as you will likely
+ run into other problems. If nothing works you can try this in your
+ .profile.
+
+ printf '\33]701;%s\007' "$LC_CTYPE" # $LANG or $LC_ALL are worth a try, too
+
+ If this doesn't work, then maybe you use a "LC_CTYPE" specification not
+ supported on your systems. Some systems have a "locale" command which
+ displays this (also, "perl -e0" can be used to check locale settings, as
+ it will complain loudly if it cannot set the locale). If it displays
+ something like:
+
+ locale: Cannot set LC_CTYPE to default locale: ...
+
+ Then the locale you specified is not supported on your system.
+
+ If nothing works and you are sure that everything is set correctly then
+ you will need to remember a little known fact: Some programs just don't
+ support locales :(
+
+ How does rxvt-unicode determine the encoding to use?
+ See next entry.
+
+ Is there an option to switch encodings?
+ Unlike some other terminals, rxvt-unicode has no encoding switch, and no
+ specific "utf-8" mode, such as xterm. In fact, it doesn't even know
+ about UTF-8 or any other encodings with respect to terminal I/O.
+
+ The reasons is that there exists a perfectly fine mechanism for
+ selecting the encoding, doing I/O and (most important) communicating
+ this to all applications so everybody agrees on character properties
+ such as width and code number. This mechanism is the *locale*.
+ Applications not using that info will have problems (for example,
+ "xterm" gets the width of characters wrong as it uses its own,
+ locale-independent table under all locales).
+
+ Rxvt-unicode uses the "LC_CTYPE" locale category to select encoding. All
+ programs doing the same (that is, most) will automatically agree in the
+ interpretation of characters.
+
+ Unfortunately, there is no system-independent way to select locales, nor
+ is there a standard on how locale specifiers will look like.
+
+ On most systems, the content of the "LC_CTYPE" environment variable
+ contains an arbitrary string which corresponds to an already-installed
+ locale. Common names for locales are "en_US.UTF-8", "de_DE.ISO-8859-15",
+ "ja_JP.EUC-JP", i.e. "language_country.encoding", but other forms (i.e.
+ "de" or "german") are also common.
+
+ Rxvt-unicode ignores all other locale categories, and except for the
+ encoding, ignores country or language-specific settings, i.e.
+ "de_DE.UTF-8" and "ja_JP.UTF-8" are the normally same to rxvt-unicode.
+
+ If you want to use a specific encoding you have to make sure you start
+ rxvt-unicode with the correct "LC_CTYPE" category.
+
+ Can I switch locales at runtime?
+ Yes, using an escape sequence. Try something like this, which sets
+ rxvt-unicode's idea of "LC_CTYPE".
+
+ printf '\33]701;%s\007' ja_JP.SJIS
+
+ See also the previous answer.
+
+ Sometimes this capability is rather handy when you want to work in one
+ locale (e.g. "de_DE.UTF-8") but some programs don't support it (e.g.
+ UTF-8). For example, I use this script to start "xjdic", which first
+ switches to a locale supported by xjdic and back later:
+
+ printf '\33]701;%s\007' ja_JP.SJIS
+ xjdic -js
+ printf '\33]701;%s\007' de_DE.UTF-8
+
+ You can also use xterm's "luit" program, which usually works fine,
+ except for some locales where character width differs between program-
+ and rxvt-unicode-locales.
+
+ I have problems getting my input method working.
+ Try a search engine, as this is slightly different for every input
+ method server.
+
+ Here is a checklist:
+
+ - Make sure your locale *and* the imLocale are supported on your OS.
+ Try "locale -a" or check the documentation for your OS.
+
+ - Make sure your locale or imLocale matches a locale supported by your
+ XIM.
+ For example, kinput2 does not support UTF-8 locales, you should use
+ "ja_JP.EUC-JP" or equivalent.
+
+ - Make sure your XIM server is actually running.
+ - Make sure the "XMODIFIERS" environment variable is set correctly when
+ *starting* rxvt-unicode.
+ When you want to use e.g. kinput2, it must be set to "@im=kinput2".
+ For scim, use "@im=SCIM". You can see what input method servers are
+ running with this command:
+
+ xprop -root XIM_SERVERS
+
+
+
+ My input method wants <some encoding> but I want UTF-8, what can I do?
+ You can specify separate locales for the input method and the rest of
+ the terminal, using the resource "imlocale":
+
+ URxvt.imlocale: ja_JP.EUC-JP
+
+ Now you can start your terminal with "LC_CTYPE=ja_JP.UTF-8" and still
+ use your input method. Please note, however, that, depending on your
+ Xlib version, you may not be able to input characters outside "EUC-JP"
+ in a normal way then, as your input method limits you.
+
+ Rxvt-unicode crashes when the X Input Method changes or exits.
+ Unfortunately, this is unavoidable, as the XIM protocol is racy by
+ design. Applications can avoid some crashes at the expense of memory
+ leaks, and Input Methods can avoid some crashes by careful ordering at
+ exit time. kinput2 (and derived input methods) generally succeeds, while
+ SCIM (or similar input methods) fails. In the end, however, crashes
+ cannot be completely avoided even if both sides cooperate.
+
+ So the only workaround is not to kill your Input Method Servers.
+
+ Operating Systems / Package Maintaining
+ I am using Debian GNU/Linux and have a problem...
+ The Debian GNU/Linux package of rxvt-unicode in sarge contains large
+ patches that considerably change the behaviour of rxvt-unicode (but
+ unfortunately this notice has been removed). Before reporting a bug to
+ the original rxvt-unicode author please download and install the genuine
+ version (<http://software.schmorp.de#rxvt-unicode>) and try to reproduce
+ the problem. If you cannot, chances are that the problems are specific
+ to Debian GNU/Linux, in which case it should be reported via the Debian
+ Bug Tracking System (use "reportbug" to report the bug).
+
+ For other problems that also affect the Debian package, you can and
+ probably should use the Debian BTS, too, because, after all, it's also a
+ bug in the Debian version and it serves as a reminder for other users
+ that might encounter the same issue.
+
+ I am maintaining rxvt-unicode for distribution/OS XXX, any recommendation?
+ You should build one binary with the default options. configure now
+ enables most useful options, and the trend goes to making them
+ runtime-switchable, too, so there is usually no drawback to enabling
+ them, except higher disk and possibly memory usage. The perl interpreter
+ should be enabled, as important functionality (menus, selection, likely
+ more in the future) depends on it.
+
+ You should not overwrite the "perl-ext-common" snd "perl-ext" resources
+ system-wide (except maybe with "defaults"). This will result in useful
+ behaviour. If your distribution aims at low memory, add an empty
+ "perl-ext-common" resource to the app-defaults file. This will keep the
+ perl interpreter disabled until the user enables it.
+
+ If you can/want build more binaries, I recommend building a minimal one
+ with "--disable-everything" (very useful) and a maximal one with
+ "--enable-everything" (less useful, it will be very big due to a lot of
+ encodings built-in that increase download times and are rarely used).
+
+ I need to make it setuid/setgid to support utmp/ptys on my OS, is this safe?
+ It should be, starting with release 7.1. You are encouraged to properly
+ install urxvt with privileges necessary for your OS now.
+
+ When rxvt-unicode detects that it runs setuid or setgid, it will fork
+ into a helper process for privileged operations (pty handling on some
+ systems, utmp/wtmp/lastlog handling on others) and drop privileges
+ immediately. This is much safer than most other terminals that keep
+ privileges while running (but is more relevant to urxvt, as it contains
+ things as perl interpreters, which might be "helpful" to attackers).
+
+ This forking is done as the very first within main(), which is very
+ early and reduces possible bugs to initialisation code run before
+ main(), or things like the dynamic loader of your system, which should
+ result in very little risk.
+
+ I am on FreeBSD and rxvt-unicode does not seem to work at all.
+ Rxvt-unicode requires the symbol "__STDC_ISO_10646__" to be defined in
+ your compile environment, or an implementation that implements it,
+ whether it defines the symbol or not. "__STDC_ISO_10646__" requires that
+ wchar_t is represented as unicode.
+
+ As you might have guessed, FreeBSD does neither define this symbol nor
+ does it support it. Instead, it uses its own internal representation of
+ wchar_t. This is, of course, completely fine with respect to standards.
+
+ However, that means rxvt-unicode only works in "POSIX", "ISO-8859-1" and
+ "UTF-8" locales under FreeBSD (which all use Unicode as wchar_t).
+
+ "__STDC_ISO_10646__" is the only sane way to support multi-language apps
+ in an OS, as using a locale-dependent (and non-standardized)
+ representation of wchar_t makes it impossible to convert between wchar_t
+ (as used by X11 and your applications) and any other encoding without
+ implementing OS-specific-wrappers for each and every locale. There
+ simply are no APIs to convert wchar_t into anything except the current
+ locale encoding.
+
+ Some applications (such as the formidable mlterm) work around this by
+ carrying their own replacement functions for character set handling with
+ them, and either implementing OS-dependent hacks or doing multiple
+ conversions (which is slow and unreliable in case the OS implements
+ encodings slightly different than the terminal emulator).
+
+ The rxvt-unicode author insists that the right way to fix this is in the
+ system libraries once and for all, instead of forcing every app to carry
+ complete replacements for them :)
+
+ How can I use rxvt-unicode under cygwin?
+ rxvt-unicode should compile and run out of the box on cygwin, using the
+ X11 libraries that come with cygwin. libW11 emulation is no longer
+ supported (and makes no sense, either, as it only supported a single
+ font). I recommend starting the X-server in "-multiwindow" or
+ "-rootless" mode instead, which will result in similar look&feel as the
+ old libW11 emulation.
+
+ At the time of this writing, cygwin didn't seem to support any
+ multi-byte encodings (you might try "LC_CTYPE=C-UTF-8"), so you are
+ likely limited to 8-bit encodings.
+
+ Character widths are not correct.
+ urxvt uses the system wcwidth function to know the information about the
+ width of characters, so on systems with incorrect locale data you will
+ likely get bad results. Two notorious examples are Solaris 9, where
+ single-width characters like U+2514 are reported as double-width, and
+ Darwin 8, where combining chars are reported having width 1.
+
+ The solution is to upgrade your system or switch to a better one. A
+ possibly working workaround is to use a wcwidth implementation like
+
+ http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
+
+ I want 256 colors
+ Are you sure you need 256 colors? 88 colors should be enough for most
+ purposes. If you really need more, there is an unsupported patch for it
+ in the doc directory, but please do not ask for it to be applied.