1 ## Why does st not handle utmp entries?
3 Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
6 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
8 It means that st doesn’t have any terminfo entry on your system. Chances are
9 you did not `make install`. If you just want to test it without installing it,
10 you can manually run `tic -sx st.info`.
13 ## Nothing works, and nothing is said about an unknown terminal!
15 * Some programs just assume they’re running in xterm i.e. they don’t rely on
16 terminfo. What you see is the current state of the “xterm compliance”.
17 * Some programs don’t complain about the lacking st description and default to
18 another terminal. In that case see the question about terminfo.
21 ## How do I scroll back up?
23 * Using a terminal multiplexer.
24 * `st -e tmux` using C-b [
25 * `st -e screen` using C-a ESC
26 * Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
27 * Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
30 ## I would like to have utmp and/or scroll functionality by default
32 You can add the absolute patch of both programs in your config.h
33 file. You only have to modify the value of utmp and scroll variables.
36 ## Why doesn't the Del key work in some programs?
38 Taken from the terminfo manpage:
40 If the terminal has a keypad that transmits codes when the keys
41 are pressed, this information can be given. Note that it is not
42 possible to handle terminals where the keypad only works in
43 local (this applies, for example, to the unshifted HP 2621 keys).
44 If the keypad can be set to transmit or not transmit, give these
45 codes as smkx and rmkx. Otherwise the keypad is assumed to
48 In the st case smkx=E[?1hE= and rmkx=E[?1lE>, so it is mandatory that
49 applications which want to test against keypad keys send these
52 But buggy applications (like bash and irssi, for example) don't do this. A fast
53 solution for them is to use the following command:
55 $ printf '\033[?1h\033=' >/dev/tty
60 In the case of bash, readline is used. Readline has a different note in its
61 manpage about this issue:
64 When set to On, readline will try to enable the
65 application keypad when it is called. Some systems
66 need this to enable arrow keys.
68 Adding this option to your .inputrc will fix the keypad problem for all
69 applications using readline.
71 If you are using zsh, then read the zsh FAQ
72 <http://zsh.sourceforge.net/FAQ/zshfaq03.html#l25>:
74 It should be noted that the O / [ confusion can occur with other keys
75 such as Home and End. Some systems let you query the key sequences
76 sent by these keys from the system's terminal database, terminfo.
77 Unfortunately, the key sequences given there typically apply to the
78 mode that is not the one zsh uses by default (it's the "application"
79 mode rather than the "raw" mode). Explaining the use of terminfo is
80 outside of the scope of this FAQ, but if you wish to use the key
81 sequences given there you can tell the line editor to turn on
82 "application" mode when it starts and turn it off when it stops:
84 function zle-line-init () { echoti smkx }
85 function zle-line-finish () { echoti rmkx }
87 zle -N zle-line-finish
89 Putting these lines into your .zshrc will fix the problems.
92 ## How can I use meta in 8bit mode?
94 St supports meta in 8bit mode, but the default terminfo entry doesn't
95 use this capability. If you want it, you have to use the 'st-meta' value
99 ## I cannot compile st in OpenBSD
101 OpenBSD lacks librt, despite it being mandatory in POSIX
102 <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13>.
103 If you want to compile st for OpenBSD you have to remove -lrt from config.mk, and
104 st will compile without any loss of functionality, because all the functions are
105 included in libc on this platform.
108 ## The Backspace Case
110 St is emulating the Linux way of handling backspace being delete and delete being
113 This is an issue that was discussed in suckless mailing list
114 <https://lists.suckless.org/dev/1404/20697.html>. Here is why some old grumpy
115 terminal users wants its backspace to be how he feels it:
117 Well, I am going to comment why I want to change the behaviour
118 of this key. When ASCII was defined in 1968, communication
119 with computers was done using punched cards, or hardcopy
120 terminals (basically a typewriter machine connected with the
121 computer using a serial port). ASCII defines DELETE as 7F,
122 because, in punched-card terms, it means all the holes of the
123 card punched; it is thus a kind of 'physical delete'. In the
124 same way, the BACKSPACE key was a non-destructive backspace,
125 as on a typewriter. So, if you wanted to delete a character,
126 you had to BACKSPACE and then DELETE. Another use of BACKSPACE
127 was to type accented characters, for example 'a BACKSPACE `'.
128 The VT100 had no BACKSPACE key; it was generated using the
129 CONTROL key as another control character (CONTROL key sets to
130 0 b7 b6 b5, so it converts H (code 0x48) into BACKSPACE (code
131 0x08)), but it had a DELETE key in a similar position where
132 the BACKSPACE key is located today on common PC keyboards.
133 All the terminal emulators emulated the difference between
134 these keys correctly: the backspace key generated a BACKSPACE
135 (^H) and delete key generated a DELETE (^?).
137 But a problem arose when Linus Torvalds wrote Linux. Unlike
138 earlier terminals, the Linux virtual terminal (the terminal
139 emulator integrated in the kernel) returned a DELETE when
140 backspace was pressed, due to the VT100 having a DELETE key in
141 the same position. This created a lot of problems (see [1]
142 and [2]). Since Linux has become the king, a lot of terminal
143 emulators today generate a DELETE when the backspace key is
144 pressed in order to avoid problems with Linux. The result is
145 that the only way of generating a BACKSPACE on these systems
146 is by using CONTROL + H. (I also think that emacs had an
147 important point here because the CONTROL + H prefix is used
148 in emacs in some commands (help commands).)
150 From point of view of the kernel, you can change the key
151 for deleting a previous character with stty erase. When you
152 connect a real terminal into a machine you describe the type
153 of terminal, so getty configures the correct value of stty
154 erase for this terminal. In the case of terminal emulators,
155 however, you don't have any getty that can set the correct
156 value of stty erase, so you always get the default value.
157 For this reason, it is necessary to add 'stty erase ^H' to your
158 profile if you have changed the value of the backspace key.
159 Of course, another solution is for st itself to modify the
160 value of stty erase. I usually have the inverse problem:
161 when I connect to non-Unix machines, I have to press CONTROL +
162 h to get a BACKSPACE. The inverse problem occurs when a user
163 connects to my Unix machines from a different system with a
164 correct backspace key.
166 [1] http://www.ibb.net/~anne/keyboard.html
167 [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
170 ## But I really want the old grumpy behaviour of my terminal
174 [1] https://st.suckless.org/patches/delkey
177 ## Why do images not work in st using the w3m image hack?
179 w3mimg uses a hack that draws an image on top of the terminal emulator Drawable
180 window. The hack relies on the terminal to use a single buffer to draw its
183 st uses double-buffered drawing so the image is quickly replaced and may show a
184 short flicker effect.
186 Below is a patch example to change st double-buffering to a single Drawable
189 diff --git a/x.c b/x.c
192 @@ -732,10 +732,6 @@ xresize(int col, int row)
193 win.tw = col * win.cw;
194 win.th = row * win.ch;
196 - XFreePixmap(xw.dpy, xw.buf);
197 - xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
198 - DefaultDepth(xw.dpy, xw.scr));
199 - XftDrawChange(xw.draw, xw.buf);
200 xclear(0, 0, win.w, win.h);
202 /* resize to new width */
203 @@ -1148,8 +1144,7 @@ xinit(int cols, int rows)
204 gcvalues.graphics_exposures = False;
205 dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
207 - xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
208 - DefaultDepth(xw.dpy, xw.scr));
210 XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
211 XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
213 @@ -1632,8 +1627,6 @@ xdrawline(Line line, int x1, int y1, int x2)
217 - XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, 0, 0, win.w,
219 XSetForeground(xw.dpy, dc.gc,
220 dc.col[IS_SET(MODE_REVERSE)?
221 defaultfg : defaultbg].pixel);
224 ## BadLength X error in Xft when trying to render emoji
226 Xft makes st crash when rendering color emojis with the following error:
228 "X Error of failed request: BadLength (poly request too large or internal Xlib length error)"
229 Major opcode of failed request: 139 (RENDER)
230 Minor opcode of failed request: 20 (RenderAddGlyphs)
231 Serial number of failed request: 1595
232 Current serial number in output stream: 1818"
234 This is a known bug in Xft (not st) which happens on some platforms and
235 combination of particular fonts and fontconfig settings.
238 https://gitlab.freedesktop.org/xorg/lib/libxft/issues/6
239 https://bugs.freedesktop.org/show_bug.cgi?id=107534
240 https://bugzilla.redhat.com/show_bug.cgi?id=1498269
242 The solution is to remove color emoji fonts or disable this in the fontconfig
243 XML configuration. As an ugly workaround (which may work only on newer
244 fontconfig versions (FC_COLOR)), the following code can be used to mask color
247 FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
249 Please don't bother reporting this bug to st, but notify the upstream Xft
250 developers about fixing this bug.