1 ## Why does st not handle utmp entries?
3 Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
5 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
7 It means that st doesn’t have any terminfo entry on your system. Chances are
8 you did not `make install`. If you just want to test it without installing it,
9 you can manually run `tic -sx st.info`.
11 ## Nothing works, and nothing is said about an unknown terminal!
13 * Some programs just assume they’re running in xterm i.e. they don’t rely on
14 terminfo. What you see is the current state of the “xterm compliance”.
15 * Some programs don’t complain about the lacking st description and default to
16 another terminal. In that case see the question about terminfo.
18 ## How do I scroll back up?
20 * Using a terminal multiplexer.
21 * `st -e tmux` using C-b [
22 * `st -e screen` using C-a ESC
23 * Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
24 * Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
26 ## I would like to have utmp and/or scroll functionality by default
28 You can add the absolute patch of both programs in your config.h
29 file. You only have to modify the value of utmp and scroll variables.
31 ## Why doesn't the Del key work in some programs?
33 Taken from the terminfo manpage:
35 If the terminal has a keypad that transmits codes when the keys
36 are pressed, this information can be given. Note that it is not
37 possible to handle terminals where the keypad only works in
38 local (this applies, for example, to the unshifted HP 2621 keys).
39 If the keypad can be set to transmit or not transmit, give these
40 codes as smkx and rmkx. Otherwise the keypad is assumed to
43 In the st case smkx=E[?1hE= and rmkx=E[?1lE>, so it is mandatory that
44 applications which want to test against keypad keys send these
47 But buggy applications (like bash and irssi, for example) don't do this. A fast
48 solution for them is to use the following command:
50 $ printf '\033[?1h\033=' >/dev/tty
55 In the case of bash, readline is used. Readline has a different note in its
56 manpage about this issue:
59 When set to On, readline will try to enable the
60 application keypad when it is called. Some systems
61 need this to enable arrow keys.
63 Adding this option to your .inputrc will fix the keypad problem for all
64 applications using readline.
66 If you are using zsh, then read the zsh FAQ
67 <http://zsh.sourceforge.net/FAQ/zshfaq03.html#l25>:
69 It should be noted that the O / [ confusion can occur with other keys
70 such as Home and End. Some systems let you query the key sequences
71 sent by these keys from the system's terminal database, terminfo.
72 Unfortunately, the key sequences given there typically apply to the
73 mode that is not the one zsh uses by default (it's the "application"
74 mode rather than the "raw" mode). Explaining the use of terminfo is
75 outside of the scope of this FAQ, but if you wish to use the key
76 sequences given there you can tell the line editor to turn on
77 "application" mode when it starts and turn it off when it stops:
79 function zle-line-init () { echoti smkx }
80 function zle-line-finish () { echoti rmkx }
82 zle -N zle-line-finish
84 Putting these lines into your .zshrc will fix the problems.
86 ## How can I use meta in 8bit mode?
88 St supports meta in 8bit mode, but the default terminfo entry doesn't
89 use this capability. If you want it, you have to use the 'st-meta' value
92 ## I cannot compile st in OpenBSD
94 OpenBSD lacks librt, despite it being mandatory in POSIX
95 <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13>.
96 If you want to compile st for OpenBSD you have to remove -lrt from config.mk, and
97 st will compile without any loss of functionality, because all the functions are
98 included in libc on this platform.
100 ## The Backspace Case
102 St is emulating the Linux way of handling backspace being delete and delete being
105 This is an issue that was discussed in suckless mailing list
106 <https://lists.suckless.org/dev/1404/20697.html>. Here is why some old grumpy
107 terminal users wants its backspace to be how he feels it:
109 Well, I am going to comment why I want to change the behaviour
110 of this key. When ASCII was defined in 1968, communication
111 with computers was done using punched cards, or hardcopy
112 terminals (basically a typewriter machine connected with the
113 computer using a serial port). ASCII defines DELETE as 7F,
114 because, in punched-card terms, it means all the holes of the
115 card punched; it is thus a kind of 'physical delete'. In the
116 same way, the BACKSPACE key was a non-destructive backspace,
117 as on a typewriter. So, if you wanted to delete a character,
118 you had to BACKSPACE and then DELETE. Another use of BACKSPACE
119 was to type accented characters, for example 'a BACKSPACE `'.
120 The VT100 had no BACKSPACE key; it was generated using the
121 CONTROL key as another control character (CONTROL key sets to
122 0 b7 b6 b5, so it converts H (code 0x48) into BACKSPACE (code
123 0x08)), but it had a DELETE key in a similar position where
124 the BACKSPACE key is located today on common PC keyboards.
125 All the terminal emulators emulated the difference between
126 these keys correctly: the backspace key generated a BACKSPACE
127 (^H) and delete key generated a DELETE (^?).
129 But a problem arose when Linus Torvalds wrote Linux. Unlike
130 earlier terminals, the Linux virtual terminal (the terminal
131 emulator integrated in the kernel) returned a DELETE when
132 backspace was pressed, due to the VT100 having a DELETE key in
133 the same position. This created a lot of problems (see [1]
134 and [2]). Since Linux has become the king, a lot of terminal
135 emulators today generate a DELETE when the backspace key is
136 pressed in order to avoid problems with Linux. The result is
137 that the only way of generating a BACKSPACE on these systems
138 is by using CONTROL + H. (I also think that emacs had an
139 important point here because the CONTROL + H prefix is used
140 in emacs in some commands (help commands).)
142 From point of view of the kernel, you can change the key
143 for deleting a previous character with stty erase. When you
144 connect a real terminal into a machine you describe the type
145 of terminal, so getty configures the correct value of stty
146 erase for this terminal. In the case of terminal emulators,
147 however, you don't have any getty that can set the correct
148 value of stty erase, so you always get the default value.
149 For this reason, it is necessary to add 'stty erase ^H' to your
150 profile if you have changed the value of the backspace key.
151 Of course, another solution is for st itself to modify the
152 value of stty erase. I usually have the inverse problem:
153 when I connect to non-Unix machines, I have to press CONTROL +
154 h to get a BACKSPACE. The inverse problem occurs when a user
155 connects to my Unix machines from a different system with a
156 correct backspace key.
158 [1] http://www.ibb.net/~anne/keyboard.html
159 [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
161 ## But I really want the old grumpy behaviour of my terminal
165 [1] https://st.suckless.org/patches/delkey
167 ## Why do images not work in st (in programs such as w3m)?
169 This is a terrible hack that overdraws an image on top of the terminal emulator
170 window. It also relies on a very specific way the terminal draws it's contents.
172 A more proper (but limited way) would be using sixels. Which st doesn't
175 ## BadLength X error in Xft when trying to render emoji
177 Xft makes st crash when rendering color emojis with the following error:
179 "X Error of failed request: BadLength (poly request too large or internal Xlib length error)"
180 Major opcode of failed request: 139 (RENDER)
181 Minor opcode of failed request: 20 (RenderAddGlyphs)
182 Serial number of failed request: 1595
183 Current serial number in output stream: 1818"
185 This is a known bug in Xft (not st) which happens on some platforms and
186 combination of particular fonts and fontconfig settings.
189 https://gitlab.freedesktop.org/xorg/lib/libxft/issues/6
190 https://bugs.freedesktop.org/show_bug.cgi?id=107534
191 https://bugzilla.redhat.com/show_bug.cgi?id=1498269
193 The solution is to remove color emoji fonts or disable this in the fontconfig
194 XML configuration. As an ugly workaround (which may work only on newer
195 fontconfig versions (FC_COLOR)), the following code can be used to mask color
198 FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
200 Please don't bother reporting this bug to st, but notify the upstream Xft
201 developers about fixing this bug.