Add info about Backspace and Delete to the FAQ
Here is a modest attempt at cleaning it up a little bit. I changed a few phrases that seemed awkward, but I think the content is the same. -- Wolfgang Corcoran-Mathe Signed-off-by: Roberto E. Vargas Caballero <k0ga@shike2.com>
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					@ -104,54 +104,53 @@ This is an issue that was discussed in suckless mailing list
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<http://lists.suckless.org/dev/1404/20697.html>:
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					<http://lists.suckless.org/dev/1404/20697.html>:
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	Well, I am going to comment why I want to change the behaviour
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						Well, I am going to comment why I want to change the behaviour
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	of this key. When ascii was defined in 1968 communication
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						of this key. When ASCII was defined in 1968, communication
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	with computers were done using punched cards, or hardcopy
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						with computers was done using punched cards, or hardcopy
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	terminals (basically a typewritter machine connected with
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						terminals (basically a typewriter machine connected with the
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	the computer using a serial port). Due to this, ascii defines
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						computer using a serial port).  ASCII defines DELETE as 7F,
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	DELETE as 7F, because in the puched cards, it means all the
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						because, in punched-card terms, it means all the holes of the
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	holes of the card punched, so it is a kind of 'phisical
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						card punched; it is thus a kind of 'physical delete'. In the
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	delete'. In the same way, BACKSPACE key was a non destructive
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						same way, the BACKSPACE key was a non-destructive backspace,
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	back space, as in typewriter machines.  So, if you wanted
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						as on a typewriter.  So, if you wanted to delete a character,
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	to delete a character, you had to BACKSPACE and then DELETE.
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						you had to BACKSPACE and then DELETE.  Another use of BACKSPACE
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	Other use of BACKSPACE was accented characters, for example
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						was to type accented characters, for example 'a BACKSPACE `'.
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	'a BACKSPACE `'. The VT100 had no BACKSPACE key, it was
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						The VT100 had no BACKSPACE key; it was generated using the
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	generated using the CONTROL key as another control character
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						CONTROL key as another control character (CONTROL key sets to
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	(CONTROL key sets to 0 b7 b6 b5, so it converts H (code
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						0 b7 b6 b5, so it converts H (code 0x48) into BACKSPACE (code
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	0x48) into BACKSPACE (code 0x08)), but it had a DELETE key
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						0x08)), but it had a DELETE key in a similar position where
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	in a similar position where BACKSPACE key is located today
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						the BACKSPACE key is located today on common PC keyboards.
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	in common PC keyboards. All the terminal emulators emulated
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						All the terminal emulators emulated the difference between
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	correctly the difference between these keys, and backspace
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						these keys correctly: the backspace key generated a BACKSPACE
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	key generated a BACKSPACE (^H) and delete key generated a
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						(^H) and delete key generated a DELETE (^?).
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	DELETE (^?).
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	But the problem arised when Linus Torvald wrote Linux, and
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						But a problem arose when Linus Torvalds wrote Linux. Unlike
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	he did that the virtual terminal (the terminal emulator
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						earlier terminals, the Linux virtual terminal (the terminal
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	integrated in the kernel) returns a DELETE when backspace
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						emulator integrated in the kernel) returned a DELETE when
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	was pressed, due to the fact of the key in that position
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						backspace was pressed, due to the VT100 having a DELETE key in
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	in VT100 was a delete key. This created a lot of problems
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						the same position.  This created a lot of problems (see [1]
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	(you can see it in [1] and [2]), and how Linux became the
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						and [2]). Since Linux has become the king, a lot of terminal
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	king, a lot of terminal emulators today generate a DELETE
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						emulators today generate a DELETE when the backspace key is
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	when backspace key is pressed in order to avoid problems
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						pressed in order to avoid problems with Linux. The result is
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	with linux. It causes that the only way of generating a
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						that the only way of generating a BACKSPACE on these systems
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	BACKSPACE in these systems is using CONTROL + H. I also
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						is by using CONTROL + H. (I also think that emacs had an
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	think that emacs had an important point here because CONTROL
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						important point here because the CONTROL + H prefix is used
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	+ H prefix is used in emacs in some commands (help commands).
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						in emacs in some commands (help commands).)
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	From point of view of the kernel, you can change the key
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						From point of view of the kernel, you can change the key
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	for deleting a previous character with stty erase. When you
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						for deleting a previous character with stty erase. When you
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	connect a real terminal into a machine you describe the
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						connect a real terminal into a machine you describe the type
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	type of terminal, so getty configure the correct value of
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						of terminal, so getty configures the correct value of stty
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	stty erase for this terminal, but in the case of terminal
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						erase for this terminal. In the case of terminal emulators,
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	emulators you don't have any getty that can set the correct
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						however, you don't have any getty that can set the correct
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	value of stty erase, so you always get the default value.
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						value of stty erase, so you always get the default value.
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	So it means that in case of changing the value of the
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						For this reason, it is necessary to add 'stty erase ^H' to your
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	backspace keyboard, you have to add a 'stty erase ^H' into
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						profile if you have changed the value of the backspace key.
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	your profile. Of course, other solution can be that st
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						Of course, another solution is for st itself to modify the
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	itself modify the value of stty erase.  I have usually the
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						value of stty erase.  I usually have the inverse problem:
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	inverse problem, when I connect with non Unix machines, and
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						when I connect to non-Unix machines, I have to press CONTROL +
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	I have to press control + h to get a BACKSPACE, or the
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						h to get a BACKSPACE. The inverse problem occurs when a user
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	inverse, when a user connects to my unix machines from a
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						connects to my Unix machines from a different system with a
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	different system with a correct backspace key.
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						correct backspace key.
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	[1] http://www.ibb.net/~anne/keyboard.html
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						[1] http://www.ibb.net/~anne/keyboard.html
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	[2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
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						[2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
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