Hi!

Under MS-Windows, it appears that the width of the frame only can be a
multiple of the character width. Unfortunately, the width of the fringes
and scrollbars used by side-by-side windows does not always add up to full
characters -- if you use a font other than the default. The effect is that
when using side-by-side windows, you could get a partial column. (Partial
columns are not desirable, for example, they work differently when you
place the cursor on the end of a full line.)

Steps to repeat 1:
    emacs -q

    Switch to *scratch*: C-x b RET

    Evaluate:
    (set-default-font
      (create-fontset-from-ascii-font
       "-raster-Terminal-bold-r-normal-normal-8-60-96-96-c-*-ms-oemlatin"))

    Split the window using: C-x 3

    Insert a long line: C-u 37 x

    Here, the cursor is at the end of the line in the left window, it is
rendered in the right fringe. (OK)

    Go to the other window: C-x o

    Place the cursor at the end: C-x >

    Here, the cursor is visible in the partially visible column. (NOT OK)

Steps to repeat 2:

    emacs -q

     Evaluate the following:

    (set-frame-width (selected-frame) 607 nil t)
    (frame-pixel-width)

    Here, 632 is returned.

    (set-frame-width (selected-frame) 608 nil t)
    (frame-pixel-width)

    Here, 640 is returned. Clearly, the width of the frame is always a
multiple of the character width.

See also my package https://github.com/Lindydancer/multicolumn -- I use it
to set up six side-by-side windows. (Note: As this writing, it is not
updated to work-around the above problems.)

Sincerely,
    Anders Lindgren (Long time Emacs contributor)




In GNU Emacs 24.4.1 (x86_64-w64-mingw32)
 of 2014-10-21 on KAEL
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=/z/emacs --host=x86_64-w64-mingw32
 --target=x86_64-w64-mingw32 --build=x86_64-w64-mingw32 --with-wide-int
 --with-jpeg --with-xpm --with-png --with-tiff --with-rsvg --with-xml2
 --with-gnutls --with-xft --with-sound=yes --with-file-notification=yes
 --without-dbus --without-imagemagick 'CFLAGS=-Ofast
 -fomit-frame-pointer -funroll-loops -g0 -pipe' 'CPPFLAGS=-DNDEBUG
 -DDBUS_STATIC_BUILD' 'LDFLAGS=-static-libgcc -static-libstdc++ -static
 -s -Wl,-s''

Important settings:
  value of $LANG: SVE
  locale-coding-system: cp1252

Major mode: Fundamental

Minor modes in effect:
  tooltip-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<escape> x r e p o <tab> r <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Making completion list...

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
help-fns mail-prsvr mail-utils help-mode easymenu time-date tooltip
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel dos-w32
ls-lisp w32-common-fns disp-table w32-win w32-vars tool-bar dnd fontset
image regexp-opt fringe tabulated-list newcomment lisp-mode prog-mode
register page menu-bar rfn-eshadow timer select scroll-bar mouse
jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
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custom widget hashtable-print-readable backquote make-network-process
w32notify w32 multi-tty emacs)

Memory information:
((conses 16 75502 7207)
 (symbols 56 17532 0)
 (miscs 48 78 127)
 (strings 32 11014 5137)
 (string-bytes 1 283940)
 (vectors 16 9121)
 (vector-slots 8 376122 15963)
 (floats 8 55 70)
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 (buffers 960 14))