sdl@lyra.mitre.org (Steven D. Litvinchouk) (02/27/90)
I've been having trouble using the PD vt100 program (both versions 2.9
and 2.9a). When I get vt100 to come up on a custom non-interlaced
screen, it seems unable to write anything into the 24th line of the
emulation (which, counting the menu bar line, is actually the 25th or
last line on the screen). Instead, information intended for the 24th
line is actually written on the 23rd line of the emulation.
So essentially I only have a 23 line terminal emulation. In fact, if
I use vt100 to log into a unix system for which I have a special
termcap defining a 23 line terminal, then vt100 works ok.
I never had this problem with earlier versions of vt100 (e.g., v2.8).
What am I doing wrong? How can I get vt100 v2.9 and/or v2.9a to give
me a full 24 line terminal emulation on a custom screen?
Steven Litvintchouk
MITRE Corporation
Burlington Road
Bedford, MA 01730
(617)271-7753
ARPA: sdl@mbunix.mitre.org
UUCP: ...{att,decvax,genrad,ll-xn,philabs,utzoo}!linus!sdl
"Where does he get those wonderful toys?"
-- J. Nicholson
--
Steven Litvintchouk
MITRE Corporation
Burlington Road
Bedford, MA 01730
(617)271-7753
ARPA: sdl@mbunix.mitre.org
UUCP: ...{att,decvax,genrad,ll-xn,philabs,utzoo}!linus!sdl
"Where does he get those wonderful toys?"
-- J. Nicholsonlindwall@beowulf.ucsd.edu (John Lindwall) (02/28/90)
In article <SDL.90Feb27102603@lyra.lyra.mitre.org> sdl@lyra.mitre.org (Steven D. Litvinchouk) writes: >So essentially I only have a 23 line terminal emulation. In fact, if >I use vt100 to log into a unix system for which I have a special >termcap defining a 23 line terminal, then vt100 works ok. You're not doing anything wrong. I also noticed this behaviour when I switched from vt100 2.8 (I've been using vt100 for several years). I sent email to the author of the latest versions (I think it's Steve Drew, but I've since lost his email address) and he verified the bug. He said it was too late to fix for 2.9a but it will be fixed in the next release, whenever that will be. John Lindwall lindwall@beowulf.ucsd.edu
acs@pccuts.pcc.amdahl.com (Tony Sumrall) (02/28/90)
In article <SDL.90Feb27102603@lyra.lyra.mitre.org> sdl@lyra.mitre.org (Steven D. Litvinchouk) writes: > >I've been having trouble using the PD vt100 program (both versions 2.9 >and 2.9a). When I get vt100 to come up on a custom non-interlaced >screen, it seems unable to write anything into the 24th line of the >emulation (which, counting the menu bar line, is actually the 25th or >last line on the screen). Instead, information intended for the 24th >line is actually written on the 23rd line of the emulation. > >So essentially I only have a 23 line terminal emulation. In fact, if >I use vt100 to log into a unix system for which I have a special >termcap defining a 23 line terminal, then vt100 works ok. > >I never had this problem with earlier versions of vt100 (e.g., v2.8). >What am I doing wrong? How can I get vt100 v2.9 and/or v2.9a to give >me a full 24 line terminal emulation on a custom screen? > >Steven Litvintchouk >ARPA: sdl@mbunix.mitre.org >UUCP: ...{att,decvax,genrad,ll-xn,philabs,utzoo}!linus!sdl I've already responded to Steven by e-mail but I figured I'd also post a little note here to let everyone know what's going on. There is a field in GfxBase called NormalDisplayRows. This field contains the size (in pixels) of the Workbench screen (this is the field that ends up being modified by MoreRows). Prior to 2.9, VT100 pretty much ignored this field if you specified a LINES parameter. In 2.9, LINES is constrained to not exceed this value. If you do the arithmetic, you'll see that a 24-line CUSTOM screen will require about 206 pixels (10 for titlebar, 192 for the text window and 4 to allow you to pull the window down to expose the depth gadgets). Now, 2.9 will overwrite the titlebar if necessary but only about 2 scan-lines which means that the window needs to be 204 pixels high. Since this exceeds NormalDisplaRows, VT100 silently adjusts the size of the window down so that it fits within the 200 scan line limit (and accomodates only 23 text lines). I feel very strongly about honoring NormalDisplayRows (users can use MoreRows if their monitor can display more than the normal number of pixels) but I also feel very strongly that a VT100 emulator should provide at least 24 lines in all situations. If you use the Workbench screen instead of a custom one you CAN get 24 lines (VT100 doesn't need the 4 pixels to drag down the window and it will obligingly overwrite 2 scan lines of the titlebar). If you use MoreRows you can define the maximum screen size to be whatever is right for your monitor. Now for the question: how would *you* handle the situation, keeping in mind that there *are* users out there that use a TV set which can barely accomodate 200 scan lines (I was just such a user until not too long ago). There needs to be some mechanism which permits the user to tell VT100 what the maximum screen size should be; 2.9 uses NormalDisplayRows. I could simply take the LINES parameter as gospel but I took quite a lot of flack in 2.8 because users finger-checked (typed 34 instead of 24), users couldn't accurately determine how many lines would fit and so on. I've considered adding an OVERSCAN command which explicitly tells VT100 that it's OK to use more than NormalDisplayRows, adding an optional parameter to the LINES command as well as reverting to the way that 2.8 did it. As a final alternative, I've considered trying to open a window on the custom screen which has no titlebar (but I don't much like the looks of it and it complicates other things). Please consider the question and let me know (via e-mail) your considered opinion on this matter. I've asked several other folks and, if I can get consensus, will release 2.9B in a matter of days. -- Tony Sumrall responsible for VT100 2.9A (and 2.9 and 2.8a and 2.8 and...) acs@pccuts.pcc.amdahl.com <=> amdahl!pccuts!acs [ Opinions expressed herein are the author's and should not be construed to reflect the views of Amdahl Corp. ]