Some re-organizing (#1)
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								FAQ
								
								
								
								
							|  | @ -1,250 +0,0 @@ | |||
| ## Why does st not handle utmp entries? | ||||
| 
 | ||||
| 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, | ||||
| you can manually run `tic -sx st.info`. | ||||
| 
 | ||||
| 
 | ||||
| ## Nothing works, and nothing is said about an unknown terminal! | ||||
| 
 | ||||
| * Some programs just assume they’re running in xterm i.e. they don’t rely on | ||||
|   terminfo. What you see is the current state of the “xterm compliance”. | ||||
| * Some programs don’t complain about the lacking st description and default to | ||||
|   another terminal. In that case see the question about terminfo. | ||||
| 
 | ||||
| 
 | ||||
| ## How do I scroll back up? | ||||
| 
 | ||||
| * 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. | ||||
| 
 | ||||
| 
 | ||||
| ## Why doesn't the Del key work in some programs? | ||||
| 
 | ||||
| Taken from the terminfo manpage: | ||||
| 
 | ||||
| 	If the terminal has a keypad that transmits codes when the keys | ||||
| 	are pressed, this information can be given. Note that it is not | ||||
| 	possible to handle terminals where the keypad only works in | ||||
| 	local (this applies, for example, to the unshifted HP 2621 keys). | ||||
| 	If the keypad can be set to transmit or not transmit, give these | ||||
| 	codes as smkx and rmkx. Otherwise the keypad is assumed to | ||||
| 	always transmit. | ||||
| 
 | ||||
| In the st case smkx=E[?1hE= and rmkx=E[?1lE>, so it is mandatory that | ||||
| applications which want to test against keypad keys send these | ||||
| sequences. | ||||
| 
 | ||||
| But buggy applications (like bash and irssi, for example) don't do this. A fast | ||||
| solution for them is to use the following command: | ||||
| 
 | ||||
| 	$ printf '\033[?1h\033=' >/dev/tty | ||||
| 
 | ||||
| or | ||||
| 	$ tput smkx | ||||
| 
 | ||||
| In the case of bash, readline is used. Readline has a different note in its | ||||
| manpage about this issue: | ||||
| 
 | ||||
| 	enable-keypad (Off) | ||||
| 		When set to On, readline will try to enable the | ||||
| 		application keypad when it is called. Some systems | ||||
| 		need this to enable arrow keys. | ||||
| 
 | ||||
| Adding this option to your .inputrc will fix the keypad problem for all | ||||
| applications using readline. | ||||
| 
 | ||||
| If you are using zsh, then read the zsh FAQ | ||||
| <http://zsh.sourceforge.net/FAQ/zshfaq03.html#l25>: | ||||
| 
 | ||||
| 	It should be noted that the O / [ confusion can occur with other keys | ||||
| 	such as Home and End. Some systems let you query the key sequences | ||||
| 	sent by these keys from the system's terminal database, terminfo. | ||||
| 	Unfortunately, the key sequences given there typically apply to the | ||||
| 	mode that is not the one zsh uses by default (it's the "application" | ||||
| 	mode rather than the "raw" mode). Explaining the use of terminfo is | ||||
| 	outside of the scope of this FAQ, but if you wish to use the key | ||||
| 	sequences given there you can tell the line editor to turn on | ||||
| 	"application" mode when it starts and turn it off when it stops: | ||||
| 
 | ||||
| 		function zle-line-init () { echoti smkx } | ||||
| 		function zle-line-finish () { echoti rmkx } | ||||
| 		zle -N zle-line-init | ||||
| 		zle -N zle-line-finish | ||||
| 
 | ||||
| Putting these lines into your .zshrc will fix the problems. | ||||
| 
 | ||||
| 
 | ||||
| ## 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. | ||||
| 
 | ||||
| 
 | ||||
| ## I cannot compile st in OpenBSD | ||||
| 
 | ||||
| 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. | ||||
| 
 | ||||
| 
 | ||||
| ## 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 | ||||
| <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 | ||||
| 	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 | ||||
| 	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. | ||||
| 	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 | ||||
| 
 | ||||
| 
 | ||||
| ## 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. | ||||
							
								
								
									
										17
									
								
								LEGACY
								
								
								
								
							
							
						
						
									
										17
									
								
								LEGACY
								
								
								
								
							|  | @ -1,17 +0,0 @@ | |||
| A STATEMENT ON LEGACY SUPPORT | ||||
| 
 | ||||
| In the terminal world there is much cruft that comes from old and unsup‐ | ||||
| ported terminals that inherit incompatible modes  and  escape  sequences | ||||
| which noone is able to know, except when he/she comes from that time and | ||||
| developed a graphical vt100 emulator at that time. | ||||
| 
 | ||||
| One  goal  of  st is to only support what is really needed. When you en‐ | ||||
| counter a sequence which you really need, implement it.  But  while  you | ||||
| are  at it,  do not add the other cruft you might encounter while sneek‐ | ||||
| ing at other terminal emulators. History has bloated them and  there  is | ||||
| no real evidence that most of the sequences are used today. | ||||
| 
 | ||||
| 
 | ||||
| Christoph Lohmann <20h@r-36.net> | ||||
| 2012-09-13T07:00:36.081271045+02:00 | ||||
| 
 | ||||
							
								
								
									
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								TODO
								
								
								
								
							
							
						
						
									
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								TODO
								
								
								
								
							|  | @ -1,28 +0,0 @@ | |||
| vt emulation | ||||
| ------------ | ||||
| 
 | ||||
| * double-height support | ||||
| 
 | ||||
| code & interface | ||||
| ---------------- | ||||
| 
 | ||||
| * add a simple way to do multiplexing | ||||
| 
 | ||||
| drawing | ||||
| ------- | ||||
| * add diacritics support to xdraws() | ||||
| 	* switch to a suckless font drawing library | ||||
| * make the font cache simpler | ||||
| * add better support for brightening of the upper colors | ||||
| 
 | ||||
| bugs | ||||
| ---- | ||||
| 
 | ||||
| * fix shift up/down (shift selection in emacs) | ||||
| * remove DEC test sequence when appropriate | ||||
| 
 | ||||
| misc | ||||
| ---- | ||||
| 
 | ||||
|     $ grep -nE 'XXX|TODO' st.c | ||||
| 
 | ||||
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