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diff --git a/FAQ b/FAQ
index 2ee5ec7a2c7012a8300c2ba6d904dd7c0aebf879..0f9609d57e283d6662ee912e303863857682611f 100644 (file)
--- a/FAQ
+++ b/FAQ
@@ -1,12 +1,14 @@
 ## Why does st not handle utmp entries?
 
 ## Why does st not handle utmp entries?
 

-Use the excellent tool of [utmp](http://git.suckless.org/utmp/) for this task.
+Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
+

 
 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
 
 It means that st doesn’t have any terminfo entry on your system. Chances are
 you did not `make install`. If you just want to test it without installing it,
 
 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
 
 It means that st doesn’t have any terminfo entry on your system. Chances are
 you did not `make install`. If you just want to test it without installing it,

-you can manualy run `tic -s st.info`.
+you can manually run `tic -sx st.info`.
+

 
 ## Nothing works, and nothing is said about an unknown terminal!
 
 
 ## Nothing works, and nothing is said about an unknown terminal!
 


@@ -15,19 +17,21 @@ you can manualy run `tic -s st.info`.
 * Some programs don’t complain about the lacking st description and default to
   another terminal. In that case see the question about terminfo.
 
 * Some programs don’t complain about the lacking st description and default to
   another terminal. In that case see the question about terminfo.
 

-## I get some weird glitches/visual bug on _random program_!
-
-Try launching it with a different TERM: $ TERM=xterm myapp. toe(1) will give
-you a list of available terminals, but you’ll most likely switch between xterm,
-st or st-256color. The default value for TERM can be changed in config.h
-(TNAME).

 
 ## How do I scroll back up?
 
 
 ## How do I scroll back up?
 

-Using a terminal multiplexer.
+* Using a terminal multiplexer.
+       * `st -e tmux` using C-b [
+       * `st -e screen` using C-a ESC
+* Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
+* Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
+
+
+## I would like to have utmp and/or scroll functionality by default
+
+You can add the absolute patch of both programs in your config.h
+file. You only have to modify the value of utmp and scroll variables.

 
 

-* `st -e tmux` using C-b [
-* `st -e screen` using C-a ESC

 
 ## Why doesn't the Del key work in some programs?
 
 
 ## Why doesn't the Del key work in some programs?
 


@@ -51,7 +55,7 @@ solution for them is to use the following command:
        $ printf '\033[?1h\033=' >/dev/tty
 
 or
        $ printf '\033[?1h\033=' >/dev/tty
 
 or

-       $ echo $(tput smkx) >/dev/tty
+       $ tput smkx

 
 In the case of bash, readline is used. Readline has a different note in its
 manpage about this issue:
 
 In the case of bash, readline is used. Readline has a different note in its
 manpage about this issue:


@@ -84,75 +88,163 @@ If you are using zsh, then read the zsh FAQ
 
 Putting these lines into your .zshrc will fix the problems.
 
 
 Putting these lines into your .zshrc will fix the problems.
 

+

 ## How can I use meta in 8bit mode?
 
 ## How can I use meta in 8bit mode?
 

- St supports meta in 8bit mode, but the default terminfo entry doesn't
- use this capability. If you want it, you have to use the 'st-meta' value
- in TERM.
+St supports meta in 8bit mode, but the default terminfo entry doesn't
+use this capability. If you want it, you have to use the 'st-meta' value
+in TERM.
+

 
 ## I cannot compile st in OpenBSD
 
 
 ## I cannot compile st in OpenBSD
 

-OpenBSD lacks of librt, despite it begin mandatory in POSIX
+OpenBSD lacks librt, despite it being mandatory in POSIX

 <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13>.
 If you want to compile st for OpenBSD you have to remove -lrt from config.mk, and
 st will compile without any loss of functionality, because all the functions are
 included in libc on this platform.
 
 <http://pubs.opengroup.org/onlinepubs/9699919799/utilities/c99.html#tag_20_11_13>.
 If you want to compile st for OpenBSD you have to remove -lrt from config.mk, and
 st will compile without any loss of functionality, because all the functions are
 included in libc on this platform.
 

-## Backspace key does not work
+
+## The Backspace Case
+
+St is emulating the Linux way of handling backspace being delete and delete being
+backspace.

 
 This is an issue that was discussed in suckless mailing list
 
 This is an issue that was discussed in suckless mailing list

-<http://lists.suckless.org/dev/1404/20697.html>:
+<https://lists.suckless.org/dev/1404/20697.html>. Here is why some old grumpy
+terminal users wants its backspace to be how he feels it:

 
        Well, I am going to comment why I want to change the behaviour
 
        Well, I am going to comment why I want to change the behaviour

-       of this key. When ascii was defined in 1968 communication
-       with computers were done using punched cards, or hardcopy
-       terminals (basically a typewritter machine connected with
-       the computer using a serial port). Due to this, ascii defines
-       DELETE as 7F, because in the puched cards, it means all the
-       holes of the card punched, so it is a kind of 'phisical
-       delete'. In the same way, BACKSPACE key was a non destructive
-       back space, as in typewriter machines.  So, if you wanted
-       to delete a character, you had to BACKSPACE and then DELETE.
-       Other use of BACKSPACE was accented characters, for example
-       'a BACKSPACE `'. The VT100 had no BACKSPACE key, it was
-       generated using the CONTROL key as another control character
-       (CONTROL key sets to 0 b7 b6 b5, so it converts H (code
-       0x48) into BACKSPACE (code 0x08)), but it had a DELETE key
-       in a similar position where BACKSPACE key is located today
-       in common PC keyboards. All the terminal emulators emulated
-       correctly the difference between these keys, and backspace
-       key generated a BACKSPACE (^H) and delete key generated a
-       DELETE (^?).
-
-       But the problem arised when Linus Torvald wrote Linux, and
-       he did that the virtual terminal (the terminal emulator
-       integrated in the kernel) returns a DELETE when backspace
-       was pressed, due to the fact of the key in that position
-       in VT100 was a delete key. This created a lot of problems
-       (you can see it in [1] and [2]), and how Linux became the
-       king, a lot of terminal emulators today generate a DELETE
-       when backspace key is pressed in order to avoid problems
-       with linux. It causes that the only way of generating a
-       BACKSPACE in these systems is using CONTROL + H. I also
-       think that emacs had an important point here because CONTROL
-       + H prefix is used in emacs in some commands (help commands).
+       of this key. When ASCII was defined in 1968, communication
+       with computers was done using punched cards, or hardcopy
+       terminals (basically a typewriter machine connected with the
+       computer using a serial port).  ASCII defines DELETE as 7F,
+       because, in punched-card terms, it means all the holes of the
+       card punched; it is thus a kind of 'physical delete'. In the
+       same way, the BACKSPACE key was a non-destructive backspace,
+       as on a typewriter.  So, if you wanted to delete a character,
+       you had to BACKSPACE and then DELETE.  Another use of BACKSPACE
+       was to type accented characters, for example 'a BACKSPACE `'.
+       The VT100 had no BACKSPACE key; it was generated using the
+       CONTROL key as another control character (CONTROL key sets to
+       0 b7 b6 b5, so it converts H (code 0x48) into BACKSPACE (code
+       0x08)), but it had a DELETE key in a similar position where
+       the BACKSPACE key is located today on common PC keyboards.
+       All the terminal emulators emulated the difference between
+       these keys correctly: the backspace key generated a BACKSPACE
+       (^H) and delete key generated a DELETE (^?).
+
+       But a problem arose when Linus Torvalds wrote Linux. Unlike
+       earlier terminals, the Linux virtual terminal (the terminal
+       emulator integrated in the kernel) returned a DELETE when
+       backspace was pressed, due to the VT100 having a DELETE key in
+       the same position.  This created a lot of problems (see [1]
+       and [2]). Since Linux has become the king, a lot of terminal
+       emulators today generate a DELETE when the backspace key is
+       pressed in order to avoid problems with Linux. The result is
+       that the only way of generating a BACKSPACE on these systems
+       is by using CONTROL + H. (I also think that emacs had an
+       important point here because the CONTROL + H prefix is used
+       in emacs in some commands (help commands).)

 
        From point of view of the kernel, you can change the key
        for deleting a previous character with stty erase. When you
 
        From point of view of the kernel, you can change the key
        for deleting a previous character with stty erase. When you

-       connect a real terminal into a machine you describe the
-       type of terminal, so getty configure the correct value of
-       stty erase for this terminal, but in the case of terminal
-       emulators you don't have any getty that can set the correct
+       connect a real terminal into a machine you describe the type
+       of terminal, so getty configures the correct value of stty
+       erase for this terminal. In the case of terminal emulators,
+       however, you don't have any getty that can set the correct

        value of stty erase, so you always get the default value.
        value of stty erase, so you always get the default value.

-       So it means that in case of changing the value of the
-       backspace keyboard, you have to add a 'stty erase ^H' into
-       your profile. Of course, other solution can be that st
-       itself modify the value of stty erase.  I have usually the
-       inverse problem, when I connect with non Unix machines, and
-       I have to press control + h to get a BACKSPACE, or the
-       inverse, when a user connects to my unix machines from a
-       different system with a correct backspace key.
+       For this reason, it is necessary to add 'stty erase ^H' to your
+       profile if you have changed the value of the backspace key.
+       Of course, another solution is for st itself to modify the
+       value of stty erase.  I usually have the inverse problem:
+       when I connect to non-Unix machines, I have to press CONTROL +
+       h to get a BACKSPACE. The inverse problem occurs when a user
+       connects to my Unix machines from a different system with a
+       correct backspace key.

 
        [1] http://www.ibb.net/~anne/keyboard.html
        [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
 
 
        [1] http://www.ibb.net/~anne/keyboard.html
        [2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
 

+
+## But I really want the old grumpy behaviour of my terminal
+
+Apply [1].
+
+[1] https://st.suckless.org/patches/delkey
+
+
+## Why do images not work in st using the w3m image hack?
+
+w3mimg uses a hack that draws an image on top of the terminal emulator Drawable
+window. The hack relies on the terminal to use a single buffer to draw its
+contents directly.
+
+st uses double-buffered drawing so the image is quickly replaced and may show a
+short flicker effect.
+
+Below is a patch example to change st double-buffering to a single Drawable
+buffer.
+
+diff --git a/x.c b/x.c
+--- a/x.c
++++ b/x.c
+@@ -732,10 +732,6 @@ xresize(int col, int row)
+       win.tw = col * win.cw;
+       win.th = row * win.ch;
+ 
+-      XFreePixmap(xw.dpy, xw.buf);
+-      xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-                      DefaultDepth(xw.dpy, xw.scr));
+-      XftDrawChange(xw.draw, xw.buf);
+       xclear(0, 0, win.w, win.h);
+ 
+       /* resize to new width */
+@@ -1148,8 +1144,7 @@ xinit(int cols, int rows)
+       gcvalues.graphics_exposures = False;
+       dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
+                       &gcvalues);
+-      xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
+-                      DefaultDepth(xw.dpy, xw.scr));
++      xw.buf = xw.win;
+       XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
+       XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
+ 
+@@ -1632,8 +1627,6 @@ xdrawline(Line line, int x1, int y1, int x2)
+ void
+ xfinishdraw(void)
+ {
+-      XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, 0, 0, win.w,
+-                      win.h, 0, 0);
+       XSetForeground(xw.dpy, dc.gc,
+                       dc.col[IS_SET(MODE_REVERSE)?
+                               defaultfg : defaultbg].pixel);
+
+
+## BadLength X error in Xft when trying to render emoji
+
+Xft makes st crash when rendering color emojis with the following error:
+
+"X Error of failed request:  BadLength (poly request too large or internal Xlib length error)"
+  Major opcode of failed request:  139 (RENDER)
+  Minor opcode of failed request:  20 (RenderAddGlyphs)
+  Serial number of failed request: 1595
+  Current serial number in output stream:  1818"
+
+This is a known bug in Xft (not st) which happens on some platforms and
+combination of particular fonts and fontconfig settings.
+
+See also:
+https://gitlab.freedesktop.org/xorg/lib/libxft/issues/6
+https://bugs.freedesktop.org/show_bug.cgi?id=107534
+https://bugzilla.redhat.com/show_bug.cgi?id=1498269
+
+The solution is to remove color emoji fonts or disable this in the fontconfig
+XML configuration.  As an ugly workaround (which may work only on newer
+fontconfig versions (FC_COLOR)), the following code can be used to mask color
+fonts:
+
+       FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
+
+Please don't bother reporting this bug to st, but notify the upstream Xft
+developers about fixing this bug.