[gnu.emacs.bug] small POS bug in the modeline

leblanc@BOSCO.BERKELEY.EDU (04/28/89)

Emacs Version:
    "GNU Emacs 18.51.1 of Wed May 25 1988 on yuban (berkeley-unix)"

Problem:
    I started up emacs with the "-q" flag and then typed "C-x m" to get
into "mail"; POS on the modeline was "All".

    I typed lines into the buffer until I got to the line immediately
above the modeline.  After typing a few characters on the line
immediately above the modeline, and WITHOUT typing a carriage return, I
signed the mail with "C-c C-w" ("mail-signature").  POS was still "All",
although there was now text below the screen.  According to the info on
the "Mode Line":

      POS tells you whether there is additional text above the top of the
    screen, or below the bottom.  If your file is small and it is all on the
    screen, POS is `All'.  Otherwise, it is `Top' if you are looking at the
    beginning of the file, `Bot' if you are looking at the end of the file, or
    `NN%', where NN is the percentage of the file above the top of the screen.

I think the "All" should have been updated to a "Top".  Perhaps "file"
in the documentation above should be replaced with "buffer" also.

    In case it matters the .signature file I used is printed between the
lines starting with 5 asterisks below (my name is preceeded by 8 tab
characters, which may get mangled by mailers, and followed by a carriage
return):

*****

								Emile
*****

Emile LeBlanc
ARPA:  leblanc@cartan.berkeley.edu
UUCP:  {decvax,decwrl,dual,hplabs,sun,...}!ucbvax!cartan!leblanc

jr@bbn.com (John Robinson) (04/28/89)

In article <8904280029.AA10060@spam>, leblanc@BOSCO writes:
>Emacs Version:
>    "GNU Emacs 18.51.1 of Wed May 25 1988 on yuban (berkeley-unix)"
>
>Problem:
>    I started up emacs with the "-q" flag and then typed "C-x m" to get
>into "mail"; POS on the modeline was "All".
>
>    I typed lines into the buffer until I got to the line immediately
>above the modeline.  After typing a few characters on the line
>immediately above the modeline, and WITHOUT typing a carriage return, I
>signed the mail with "C-c C-w" ("mail-signature").  POS was still "All",
>although there was now text below the screen.

The problem is in mail-signature.  Any function that might cause the
modeline to need to be redisplayed has to explicitly force this to
happen.  For example, auto-insert in fact causes the % number (when
that is when is displayed) to change by a little as you type more
characters afer the top of screen, in a relativlyy small file.  But
the modeline doesn't change.  The effort to recompute the modeline on
every keystroke is simply not worth it.  Functions like mail-signature
are perhaps beter candidates, but they only mess up under contrived
circumstances.  At any rate, a ^L will fix it, as will any scroll
command (^V, M-V).
--
/jr
jr@bbn.com or bbn!jr
C'mon big money!