C70:bitgraph (07/16/82)
>From rwells@BBN-UNIX Fri Jul 16 08:41:45 1982
The gray rectangle problem appears with any system that pads with DEL
rather than NUL, because we are printing DEL that way. That was a mistake
and will be corrected in the next release.
I have not seen or heard of the rt11 screen teco problem before. Could
you tell me more about the symptoms? If stuff is getting written across
the entire screen instead of staying inside the top 24 lines, then you
aren't really in vt52 emulation mode. Both the "\e[?2l" and "\e:1e"
command sequences will put it into vt52 emulation mode.
- Robert WellsC70:bitgraph (07/16/82)
>From edmond@BBN-UNIX Fri Jul 16 14:29:34 1982
Probably the reason for the gray rectangle is the use of DEL characters
for padding functions like Insert and Delete Line. The BitGraph displays
DELs as a box, where the H19 and the VT52 discard DELs. The TOPS-20 EMACS
likes to use DEL characters for padding. Other TOPS-20 and TENEX programs
also prefer DEL to NUL, since NUL is often used as a string terminator by
operting system functions.
-WBE