VPR stands for Move cursor down a number of rows, and the code was moving
the cursor up instead of moving it down.
---
 st.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

DECOM sequence allows to the user defines a new home position. The home
position is used as base for all the movement commands except HVP and
VPA. It is important notice than DECSLM moves cursor to absolute position
0,0.
---
 st.c |   33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

After terminal reset saved terminal position is reset to 0, allowing know
where cursor will go in next restore cursor operation.
---
 st.c |    2 ++
 1 file changed, 2 insertions(+)

Since relational expresions are always evaluated to 0 or 1, we can use
bitwise xor operator instead of using more complex boolean expressions.
---
 st.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

Sequences like DECSC, DECRC, ESC [?1047l or ESC [?1047h save and restore
cursor attributes, than taken from vt100 manual are:

       Save Cursor (DECSC) ESC   7
       ===========================
       Saves the following in terminal memory.

      - cursor position
      - graphic rendition
      - character set shift state
      - state of wrap flag
      - state of origin mode

      Restore Cursor (DECRC) ESC 8
      ===========================
      Restores the states described for (DECSC) above. If none of these
      characteristics were saved, the cursor moves to home position; origin
      mode is reset; no character attributes are assigned; and the default
      character set mapping is established.

This implies that hide attribute of the cursor should not be saved/restored
in these sequences. The best way to fix this problem is moving hide
attribute into the terminal mode, instead of having it in the cursor state.
---
 st.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Thanks c00kiemon5ter!

useful, but easy to implement.

possible. Thanks!

variables. Thanks! xinit() and ttynew() had to be switched in their
call-appearance. Otherwise xw.win is not set.

not emulate the vt100 behaviour of selecting all whitespaces. Thanks!

write can write less bytes than we request, so it is necessary check the
return value, in case of error print a message and don't continnue writing
in the file.
---
 st.c |   39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

should really learn opthalmology instead. :O

This sequence was used by DEC personal in to for verifying the screen adjust
of terminals. It is the unique test sequence implemented by all the
emulators, and I think it is because they want be conforms with vttest which
uses this sequence in some tests.
---
 st.c |   31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)

If vt100_0 is a automatic variable then it is initializated in each call to
tsetchar, but if the variable is static it is initializated only in compile
time.
---
 st.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Do not send NUL character in the identification (use (sizeof(VT102ID) - 1),
and finish  the sequence once you execute it.
---
 st.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

These sequences are used by the host in order to can detect which kind of
terminal is connected. St will answer like a vt102 terminal with this patch.
---
 st.c |    9 +++++++++
 1 file changed, 9 insertions(+)

Non handled codes must be ignored, except in graphic mode. Also STR
sequences have higher priority than control codes, so they must be handled
before of them.
---
 st.c |  160 ++++++++++++++++++++++++++++++++++++------------------------------
 1 file changed, 87 insertions(+), 73 deletions(-)

SI and SO allows change the G0 and G1 selection. This implementation is not
full vt100 compatible, but it is complatible with linux virtual terminal
implementation. For full vt100 compatibility we need remake a lot of stuff
relate to the different charmaps.
---
 st.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

These control codes reset any escape sequence already initialised.
---
 st.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Add the documentation from the vt100 manual programmer:

Control 	Octal      Action Taken
Character	Code
-------------------------------------------
NUL		000	Ignored on input (not stored in input buffer;
			see full duplex protocol).
ENQ		005	Transmit answerback message.
BEL		007	Sound bell tone from keyboard.
BS		010	Move the cursor to the left one character position,
			unless it is at the left margin,
			in which case no action occurs.
HT		011	Move the cursor to the next tab stop,
			or to the right margin if no further tab stops
			are present on the line.
LF		012	This code causes a line feed or
			a new line operation. (See new line mode).
VT		013	Interpreted as LF.
FF		014	Interpreted as LF.
CR		015	Move cursor to the left margin on the current line.
SO		016	Invoke G1 character set, as designated by SCS
			control sequence.
SI		017	Select G0 character set, as selected by ESC ( sequence.
XON		021	Causes terminal to resume transmission.
XOFF		023	Causes terminal to stop transmitted all codes
			except XOFF and XON.
CAN		030	If sent during a control sequence, the sequence is
			immediately terminated and not executed. It also causes
			the error character to be displayed.
SUB		032	Interpreted as CAN.
ESC		033	Invokes a control sequence.
DEL		177	Ignored on input (not stored in input buffer).
--------------------------------------------
---
 st.c |   28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

if something needs to be drawn close to it.

infidels will be squashed too!

reasonable solution.

Thanks to Peter A. Shevtsov!

invert mode now works as expected. In the config.def.h autohint is set to
false, so the fonts are drawn correctly, without any overlapping.

right choice.

The parameters were reordered according to the alphabet too.

This is a new opportunity to see if X11 somewhen handled colors in a strange
way.

optimized. There is a speedup when resizing windows.

sequences, so we have to support escape sequences in escape sequences that
escape sequences in escape sequences – setting a title won't notify you
anymore.

Taken from vt100 manual programmer:

	Control characters (codes \0 to \37 inclusive) are specifically
	excluded from the control sequence syntax, but may be embedded
	within a control sequence. Embedded control characters are executed
	as soon as they are encountered by the VT100. The processing of the
	control sequence then continues with the next character received.
---
 st.c |   68 +++++++++++++++++++++++++++++++++---------------------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

Taken from vt100 programmer manual:

	Control characters have values of \000 - \037, and \177. The control
	characters recognized by the VT100 are shown in Table 3-10. All
	other control codes cause no action to be taken.

We have to take attention when we are using alternate charset, because in
this cases they are not used as control characters.
---
 st.c |   20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)