stterm/FAQ

## Why does st not handle utmp entries?

Use the excellent tool of [utmp](http://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 manualy run `tic -s 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.

## 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?

Using a terminal multiplexer.

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

## 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
	$ echo $(tput smkx) >/dev/tty

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 of librt, despite it begin 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.

## Backspace key does not work

This is an issue that was discussed in suckless mailing list
<http://lists.suckless.org/dev/1404/20697.html>:

	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).

	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
	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.

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