From 00419a8729baf37bcbfb5a6eec639bdd722d9161 Mon Sep 17 00:00:00 2001
From: jay <jay>
Date: Mon, 2 Jul 2007 08:42:10 +0000
Subject: [PATCH] Indicate that %A@ now includes a sub-second part on many
 systems

---
 ChangeLog     |  3 +++
 doc/find.texi | 34 ++++++----------------------------
 2 files changed, 9 insertions(+), 28 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index df92439..d9ec55a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -63,6 +63,9 @@
 	* doc/find.texi (Copying A Subset of Files): Added a new worked
 	example. 
 
+	* doc/find.texi (Updating A Timestamp File): Indicate that %A@ now
+	includes a sub-second part on many systems.
+
 2007-06-30  Eric Blake  <ebb9@byu.net>
 
 	* find/pred.c (pred_timewindow): Avoid gcc warnings.
diff --git a/doc/find.texi b/doc/find.texi
index 113f82e..c1a03e2 100644
--- a/doc/find.texi
+++ b/doc/find.texi
@@ -4284,36 +4284,14 @@ value of @code{$newest} if that variable is set, but to
 @file{timestamp} otherwise.  This ensures that an argument is always
 given to the @samp{-r} option of the @code{touch} command.
 
-This approach seems quite efficient, but unfortunately it has a bug.
-Many operating systems now keep file modification time information at
-a granularity which is finer than one second.  Unfortunately the
-@samp{%A@@} format for @samp{-printf} only prints a whole-number value
-currently; that is, these values are at a one-second granularity.
-This means that in our example above, @samp{$newest} will be the name
-of a file which is no more than one second older than the newest file,
-but may indeed be older.
+This approach seems quite efficient, but unfortunately it has a
+problem.  Many operating systems now keep file modification time
+information at a granularity which is finer than one second.
+Findutils version 4.3.3 and later will print a fractional part with
+%A@@, but older versions will not.
 
-It would be possible to solve this problem with some kind of loop:
 
-@smallexample
-while true; do
-        newest=$(find subdir -newer timestamp -printf "%A@@:%p\n" | 
-           sort -n | 
-           tail -1 | 
-           cut -d: -f2- ) 
-        if test -z "$newest" ; then
-                break
-        else
-                touch -r "$newest" timestamp
-        fi
-done
-@end smallexample
-
-A better fix for this problem would be to allow the @samp{%A@@} format
-to produce a result having a fractional part, too.  While this is
-planned for GNU @code{find}, it hasn't been done yet.
-
-@subsection Coping with sub-second timestamp resolution
+@subsection Solving the problem with make
 
 Another tool which often works with timestamps is @code{make}.  We can
 use @code{find} to generate a @file{Makefile} file on the fly and then
-- 
2.11.4.GIT