26.1; ansi-term not resized after X window resize

[Soumendra Ganguly]

Issue: ansi-term does not adjust the "terminal size" when the "emacs X
window"/frame is resized. Here "terminal size" refers to "struct winsize"/
"stty size"/"${COLUMNS}+${LINES}". As a result, say, output of ls(1)
becomes hard to parse visually. The bug was discovered on i3wm, which
is a tiling window manager, where X window size updates are frequent.

Reason: When the frame is resized, the window size changes, but processes
running in buffers are not notified of that change.

Fix: In lisp/window.el, add window--adjust-process-windows to
window-size-change-functions. Patch implementing proposed fix
follows.

Signed-off-by: Soumendra Ganguly <soumendraganguly@gmail.com>
---

--- emacs/lisp/window.el        2020-08-30 17:00:47.763965814 -0500
+++ window.el   2020-08-30 16:52:39.053035140 -0500
@@ -10166,6 +10166,11 @@
               (when size
                 (set-process-window-size process (cdr size) (car size))))))))))

+(defun frame-resize-adjust-process-windows (frame)
+  (window--adjust-process-windows))
+
+(add-hook 'window-size-change-functions 'frame-resize-adjust-process-windows)
+
 (add-hook 'window-configuration-change-hook 'window--adjust-process-windows)
 
 ;; Some of these are in tutorial--default-keys, so update that if you

---

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Loading /var/cache/dictionaries-common/emacsen-ispell-dicts.el (source)...done
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