(du invocation): New options --last-time and --time-style.

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index 7d64b68e44f6709f698cfbe5a7ea62e051040e52..75910a59727aeeda7a6ab4fb12ece13b14787267 100644 (file)
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -9004,6 +9004,30 @@ Dereference symbolic links (show the disk space used by the file
 or directory that the link points to instead of the space used by
 the link).
 
+@itemx --last-time
+@opindex --last-time
+@cindex last modified dates, displaying in @command{du}
+Show time of the most recent modification of any file in the directory,
+or any of its subdirectories.
+
+@itemx --last-time=ctime
+@itemx --last-time=status
+@itemx --last-time=use
+@opindex --last-time
+@opindex ctime@r{, show the most recent}
+@opindex status time@r{, show the most recent}
+@opindex use time@r{, show the most recent}
+Show the most recent status change time (the @samp{ctime} in the inode) of
+any file in the directory, instead of the modification time.
+
+@itemx --last-time=atime
+@itemx --last-time=access
+@opindex --last-time
+@opindex atime@r{, show the most recent}
+@opindex access time@r{, show the most recent}
+Show the most recent access time (the @samp{atime} in the inode) of
+any file in the directory, instead of the modification time.
+
 @item -P
 @itemx --no-dereference
 @opindex -P
@@ -9049,6 +9073,78 @@ Display only a total for each argument.
 Report the size of each directory separately, not including the sizes
 of subdirectories.
 
+@item --time-style=@var{style}
+@opindex --time-style
+@cindex time style
+Implicity selects the option @option{--last-time} to show last modified
+date if an explicit @option{--last-time} option has not been selected.
+List timestamps in style @var{style}.  The @var{style} should
+be one of the following:
+
+@table @samp
+@item +@var{format}
+@vindex LC_TIME
+List timestamps using @var{format}, where @var{format} is interpreted
+like the format argument of @command{date} (@pxref{date invocation}).
+For example, @option{--time-style="+%Y-%m-%d %H:%M:%S"} causes
+@command{du} to list timestamps like @samp{2002-03-30 23:45:56}.  As
+with @command{date}, @var{format}'s interpretation is affected by the
+@env{LC_TIME} locale category.
+
+@item full-iso
+List timestamps in full using @acronym{ISO} 8601 date, time, and time zone
+format with nanosecond precision, e.g., @samp{2002-03-30
+23:45:56.477817180 -0700}.  This style is equivalent to
+@samp{+%Y-%m-%d %H:%M:%S.%N %z}.
+
+@item long-iso
+List @acronym{ISO} 8601 date and time in minutes, e.g.,
+@samp{2002-03-30 23:45}.  These timestamps are shorter than
+@samp{full-iso} timestamps, and are usually good enough for everyday
+work.  This style is equivalent to @samp{%Y-%m-%d %H:%M}.
+
+@item iso
+List @acronym{ISO} 8601 dates for timestamps
+
+@item locale
+@vindex LC_TIME
+List timestamps in a locale-dependent form.  For example, a Finnish
+locale might list timestamps like @samp{maalis 30@ @ 2002}.
+Locale-dependent timestamps typically consume more space than @samp{iso}
+timestamps and are harder for programs to parse because locale
+conventions vary so widely, but they are easier for many people to read.
+
+The @env{LC_TIME} locale category specifies the timestamp format.  The
+default @acronym{POSIX} locale uses timestamps like @samp{Mar 30@
+@ 2002}; in this locale, the following two @command{du} invocations are
+equivalent:
+
+@example
+du --last-time --time-style="+%b %e %Y"
+du --last-time --time-style="locale"
+@end example
+
+Other locales behave differently.  For example, in a German locale,
+@option{--time-style="locale"} might be equivalent to
+@option{--time-style="+%e. %b %Y"}
+and might generate timestamps like @samp{30. M@"ar 2002@ }.
+
+@item posix-@var{style}
+@vindex LC_TIME
+List @acronym{POSIX}-locale timestamps if the @env{LC_TIME} locale
+category is @acronym{POSIX}, @var{style} timestamps otherwise.  For
+example, the default style, which is @samp{posix-long-iso}, lists
+timestamps like @samp{Mar 30@ @ 2002} when in
+the @acronym{POSIX} locale, and like @samp{2002-03-30 23:45} otherwise.
+@end table
+
+@vindex TIME_STYLE
+You can specify the default value of the @option{--time-style} option
+with the environment variable @env{TIME_STYLE}; if @env{TIME_STYLE} is not set
+the default style is @samp{posix-long-iso}. If @env{TIME_STYLE} contains two
+styles, separated by a newline (for @command{ls}), the @command{du} uses only
+the first of the two styles.
+
 @item -x
 @itemx --one-file-system
 @opindex -x