doc: factor out --files0-from duplication

* coreutils.texi (wc invocation) [files0fromOption]: New macro.  Use it.
(du invocation): Use it here, too.

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index ee7dbb2..5a6f2c3 100644 (file)
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -3074,29 +3074,32 @@ Print only the newline counts.
 @opindex --max-line-length
 Print only the maximum line lengths.
 
+@macro files0fromOption{cmd,withTotalOption}
 @itemx --files0-from=@var{FILE}
 @opindex --files0-from=@var{FILE}
-@cindex including files from @command{du}
+@cindex including files from @command{\cmd\}
 Rather than processing files named on the command line, process those
 named in file @var{FILE}; each name is terminated by a null byte.
-This is useful when
-the list of file names is so long that it may exceed a command line
+This is useful \withTotalOption\
+when the list of file names is so long that it may exceed a command line
 length limitation.
-In such cases, running @command{wc} via @command{xargs} is undesirable
-because it splits the list into pieces and makes @command{wc} print a
+In such cases, running @command{\cmd\} via @command{xargs} is undesirable
+because it splits the list into pieces and makes @command{\cmd\} print a
 total for each sublist rather than for the entire list.
 One way to produce a list of null-byte-terminated file names is with @sc{gnu}
-@command{find}, using its @option{-print0} predicate.  For example, to find
-the length of the longest line in any @file{.c} or @file{.h} file in the
-current hierarchy, do this:
+@command{find}, using its @option{-print0} predicate.
+Do not specify any @var{FILE} on the command line when using this option.
+@end macro
+@files0fromOption{wc,}
+
+For example, to find the length of the longest line in any @file{.c} or
+@file{.h} file in the current hierarchy, do this:
 
 @example
 find . -name '*.[ch]' -print0 |
   wc -L --files0-from=- | tail -n1
 @end example
 
-Do not specify any @var{FILE} on the command line when using this option.
-
 @end table
 
 @exitstatus
@@ -9754,20 +9757,7 @@ Does not affect other symbolic links.  This is helpful for finding
 out the disk usage of directories, such as @file{/usr/tmp}, which
 are often symbolic links.
 
-@itemx --files0-from=@var{FILE}
-@opindex --files0-from=@var{FILE}
-@cindex including files from @command{du}
-Rather than processing files named on the command line, process those
-named in file @var{FILE}; each name is terminated by a null byte.
-This is useful with the @option{--total} (@option{-c}) option when
-the list of file names is so long that it may exceed a command line
-length limitation.
-In such cases, running @command{du} via @command{xargs} is undesirable
-because it splits the list into pieces and makes @command{du} print a
-total for each sublist rather than for the entire list.
-One way to produce a list of null-byte-terminated file names is with @sc{gnu}
-@command{find}, using its @option{-print0} predicate.
-Do not specify any @var{FILE} on the command line when using this option.
+@files0fromOption{du, with the @option{--total} (@option{-c}) option}
 
 @optHumanReadable