🚀 go-pugleaf

In article <942@mcrware.UUCP> kim@mcrware.UUCP (Kim Kempf) writes:
>Why is it that the termcap entry for most vt100-style terminals define
>the arrow keys as:
>	:ku=\EOA:kd=\EOB:kr=\EOC:kl=\EOD:kb=^H:\
>when the keys actually transmit:
>	:ku=\E[A:kd=\E[B:kr=\E[C:kl=\E[D:kb=^H:\
>Some other termcaps claiming ANSI terminal compatability are defined in this
>latter method as expected.  I have an application that won't work because of
>this problem.  Is this some type of special hack that 'vi' uses and other
>applications have to know about it, or what?  Thanks in advance.

The former sequences are transmitted in ANSI (non-VT52) mode when
the Cursor Key Mode (DECCKM) is Set and the latter when it is Reset.

Before the keypad is used, it is supposed to be initialized by sending
the "ks" capability and afterwards it is supposed to be reset by sending
the "ke" capability.  This is explained in the official termcap manual
entry.  Termcap descriptions for the VT100 that use the first set of key
definitions given above should have the sequence that sets DECCKM.

For example, here's the VT100 description we use:

#
# DEC VT100
# The "vt100" entry supports the Advanced Video Option if present;
# however, AVO is not required for correct operation of the "vt100" entry.
# The following SET-UP modes are assumed for normal operation:
#	ANSI_MODE	AUTO_XON/XOFF_ON	NEWLINE_OFF	80_COLUMNS
# Other SET-UP modes may be set for operator convenience or communication
# requirements; I recommend
#	SMOOTH_SCROLL	AUTOREPEAT_ON	BLOCK_CURSOR	MARGIN_BELL_OFF
#	SHIFTED_3_#	WRAP_AROUND_ON
# Unless you have a graphics add-on such as Digital Engineering's VT640
# (and even then, whenever it can be arranged!) you should set
#	INTERLACE_OFF
# Hardware tabs are assumed to be set every 8 columns; they can be set up
# by the "reset" or "tabs" utility (use vt100-x, 132 columns, for this).
# I have included some compatible code in "rs" for the VT640 if you have one.
# No delays are specified; use "stty ixon -ixany" to enable DC3/DC1 flow control!
d0|vt100|DEC VT100:\
	:ae=^O:as=^N:bl=^G:cd=\E[J:ce=\E[K:cm=\E[%i%d;%dH:co#80:cr=^M:\
	:cs=\E[%i%d;%dr:ct=\E[3g:DO=\E[%dB:do=^J:ho=\E[H:is=\E<\E)0:it#8:\
	:k0=\EOP:k1=\EOQ:k2=\EOR:k3=\EOS:kb=^H:kd=\EOB:ke=\E[?1l\E>:kl=\EOD:\
	:kr=\EOC:ks=\E[?1h\E=:ku=\EOA:l0=PF1:l1=PF2:l2=PF3:l3=PF4:LE=\E[%dD:\
	:le=^H:li#24:ll=\E[24H:mb=\E[5m:md=\E[1m:me=\E[m:mr=\E[7m:ms:nd=\E[C:\
	:nw=\EE:rc=\E8:RI=\E[%dC:\
	:rs=^X\E<\E2\E[?9h^]\E^L^X\E[20l\E[?3;9;6l\E[r\E[m\E[q\E(B^O\E)0\E>:\
	:sc=\E7:se=\E[m:sf=^J:so=\E[7m:sr=\EM:st=\EH:ta=^I:ue=\E[m:UP=\E[%dA:\
	:up=\EM:us=\E[4m:vt#3:xo:\
	:cl=\E[H\E[J:\
	:bs:kn#4:pt:
d8|vt100-w|DEC VT100 with AVO in 132-column mode:\
	:co#132:\
	:rs=^X\E<\E2\E[?9h^]\E^L^X\E[20l\E[?9;6l\E[?3h\
\E[r\E[m\E[q\E(B^O\E)0\E>:\
	:tc=vt100:
d9|vt100-x|DEC VT100 without AVO in 132-column mode:\
	:li#14:ll=\E[14H:\
	:tc=vt100-w: