* st + patches and config
       
   URI git clone git://git.codevoid.de/st-sdk
   DIR Log
   DIR Files
   DIR Refs
   DIR README
   DIR LICENSE
       ---
       FAQ (9782B)
       ---
            1 ## Why does st not handle utmp entries?
            2 
            3 Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
            4 
            5 
            6 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
            7 
            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`.
           11 
           12 
           13 ## Nothing works, and nothing is said about an unknown terminal!
           14 
           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.
           19 
           20 
           21 ## How do I scroll back up?
           22 
           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/).
           28 
           29 
           30 ## I would like to have utmp and/or scroll functionality by default
           31 
           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.
           34 
           35 
           36 ## Why doesn't the Del key work in some programs?
           37 
           38 Taken from the terminfo manpage:
           39 
           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
           46         always transmit.
           47 
           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
           50 sequences.
           51 
           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:
           54 
           55         $ printf '\033[?1h\033=' >/dev/tty
           56 
           57 or
           58         $ tput smkx
           59 
           60 In the case of bash, readline is used. Readline has a different note in its
           61 manpage about this issue:
           62 
           63         enable-keypad (Off)
           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.
           67 
           68 Adding this option to your .inputrc will fix the keypad problem for all
           69 applications using readline.
           70 
           71 If you are using zsh, then read the zsh FAQ
           72 <http://zsh.sourceforge.net/FAQ/zshfaq03.html#l25>:
           73 
           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:
           83 
           84                 function zle-line-init () { echoti smkx }
           85                 function zle-line-finish () { echoti rmkx }
           86                 zle -N zle-line-init
           87                 zle -N zle-line-finish
           88 
           89 Putting these lines into your .zshrc will fix the problems.
           90 
           91 
           92 ## How can I use meta in 8bit mode?
           93 
           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
           96 in TERM.
           97 
           98 
           99 ## I cannot compile st in OpenBSD
          100 
          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.
          106 
          107 
          108 ## The Backspace Case
          109 
          110 St is emulating the Linux way of handling backspace being delete and delete being
          111 backspace.
          112 
          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:
          116 
          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 (^?).
          136 
          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).)
          149 
          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.
          165 
          166         [1] http://www.ibb.net/~anne/keyboard.html
          167         [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
          168 
          169 
          170 ## But I really want the old grumpy behaviour of my terminal
          171 
          172 Apply [1].
          173 
          174 [1] https://st.suckless.org/patches/delkey
          175 
          176 
          177 ## Why do images not work in st using the w3m image hack?
          178 
          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
          181 contents directly.
          182 
          183 st uses double-buffered drawing so the image is quickly replaced and may show a
          184 short flicker effect.
          185 
          186 Below is a patch example to change st double-buffering to a single Drawable
          187 buffer.
          188 
          189 diff --git a/x.c b/x.c
          190 --- a/x.c
          191 +++ 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;
          195  
          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);
          201  
          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,
          206                          &gcvalues);
          207 -        xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
          208 -                        DefaultDepth(xw.dpy, xw.scr));
          209 +        xw.buf = xw.win;
          210          XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
          211          XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
          212  
          213 @@ -1632,8 +1627,6 @@ xdrawline(Line line, int x1, int y1, int x2)
          214  void
          215  xfinishdraw(void)
          216  {
          217 -        XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, 0, 0, win.w,
          218 -                        win.h, 0, 0);
          219          XSetForeground(xw.dpy, dc.gc,
          220                          dc.col[IS_SET(MODE_REVERSE)?
          221                                  defaultfg : defaultbg].pixel);
          222 
          223 
          224 ## BadLength X error in Xft when trying to render emoji
          225 
          226 Xft makes st crash when rendering color emojis with the following error:
          227 
          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"
          233 
          234 This is a known bug in Xft (not st) which happens on some platforms and
          235 combination of particular fonts and fontconfig settings.
          236 
          237 See also:
          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
          241 
          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
          245 fonts:
          246 
          247         FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
          248 
          249 Please don't bother reporting this bug to st, but notify the upstream Xft
          250 developers about fixing this bug.