From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Sat, 31 May 2014 02:13:13 +0000 (-0400)
Subject: * lisp/subr.el (sit-for): Add comment with a short history.
X-Git-Tag: emacs-24.3.92~142
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=b701ac49455b4f8495bc639a7af1312a0266ae05;p=emacs.git

* lisp/subr.el (sit-for): Add comment with a short history.
---

diff --git a/lisp/subr.el b/lisp/subr.el
index 0a95cebd1a6..4fba469868f 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2151,6 +2151,10 @@ where the optional arg MILLISECONDS specifies an additional wait period,
 in milliseconds; this was useful when Emacs was built without
 floating point support."
   (declare (advertised-calling-convention (seconds &optional nodisp) "22.1"))
+  ;; This used to be implemented in C until the following discussion:
+  ;; http://lists.gnu.org/archive/html/emacs-devel/2006-07/msg00401.html
+  ;; Then it was moved to C using an implementation based on an idle timer,
+  ;; which was then replaced by the use of read-event.
   (if (numberp nodisp)
       (setq seconds (+ seconds (* 1e-3 nodisp))
             nodisp obsolete)