doc: clarify --zero-terminated option

* src/join.c (usage): Reword to avoid implication that
the NUL byte is only generated as the output delimeter.
* src/sort.c (usage): Likewise.
* src/shuf.c (usage): Likewise. Also since we're changing the
translation string take the opportunity to separate out
the description to a separate string to reduce translation overhead.
* src/uniq.c (usage): Likewise.
* src/stty.c (usage): s/null/NUL/ for consistency.
* src/basename.c (usage): Reword for accuracy/consistency.
* src/dirname.c (usage): Likewise.
* src/du.c (usage): Likewise.
* src/env.c (usage): Likewise.
* src/printenv.c (usage): Likewise.
* src/readlink.c (usage): Likewise.
* src/realpath.c (usage): Likewise.
* doc/coreutils.texi: Consolidate/share the descriptions of
--null, --zero and --zero-terminated.

13 files changed, 72 insertions, 72 deletions

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index a6dd075cb..243b6d745 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -583,16 +583,42 @@ Do not treat the last operand specially when it is a directory or a
 symbolic link to a directory.  @xref{Target directory}.
 @end macro
 
-@macro optNull{cmd}
-@item -0
-@opindex -0
-@itemx --null
-@opindex --null
+@macro outputNUL
 @cindex output NUL-byte-terminated lines
 Output a zero byte (ASCII NUL) at the end of each line,
 rather than a newline.  This option enables other programs to parse the
-output of @command{\cmd\} even when that output would contain data
-with embedded newlines.
+output even when that output would contain data with embedded newlines.
+@end macro
+
+@macro optNull
+@item -0
+@itemx --null
+@opindex -0
+@opindex --null
+@outputNUL
+@end macro
+
+@macro optZero
+@item -z
+@itemx --zero
+@opindex -z
+@opindex --zero
+@outputNUL
+@end macro
+
+@macro optZeroTerminated
+@item -z
+@itemx --zero-terminated
+@opindex -z
+@opindex --zero-terminated
+@cindex process zero-terminated items
+Delimit items with a zero byte rather than a newline (ASCII LF).
+I.e., treat input as items separated by ASCII NUL
+and terminate output items with ASCII NUL.
+This option can be useful in conjunction with @samp{perl -0} or
+@samp{find -print0} and @samp{xargs -0} which do the same in order to
+reliably handle arbitrary file names (even those containing blanks
+or other special characters).
 @end macro
 
 @macro optSi
@@ -4674,21 +4700,7 @@ For example, @code{sort -n -u} inspects only the value of the initial
 numeric string when checking for uniqueness, whereas @code{sort -n |
 uniq} inspects the entire line.  @xref{uniq invocation}.
 
-@macro zeroTerminatedOption
-@item -z
-@itemx --zero-terminated
-@opindex -z
-@opindex --zero-terminated
-@cindex process zero-terminated items
-Delimit items with a zero byte rather than a newline (ASCII LF).
-I.e., treat input as items separated by ASCII NUL
-and terminate output items with ASCII NUL.
-This option can be useful in conjunction with @samp{perl -0} or
-@samp{find -print0} and @samp{xargs -0} which do the same in order to
-reliably handle arbitrary file names (even those containing blanks
-or other special characters).
-@end macro
-@zeroTerminatedOption
+@optZeroTerminated
 
 @end table
 
@@ -4975,7 +4987,7 @@ typically combined with @option{--head-count}; if
 @option{--head-count} is not given, @command{shuf} repeats
 indefinitely.
 
-@zeroTerminatedOption
+@optZeroTerminated
 
 @end table
 
@@ -5228,7 +5240,7 @@ Compare at most @var{n} characters on each line (after skipping any specified
 fields and characters).  By default the entire rest of the lines are
 compared.
 
-@zeroTerminatedOption
+@optZeroTerminated
 
 @end table
 
@@ -6321,7 +6333,7 @@ character is used to delimit the fields.
 Print a line for each unpairable line in file @var{file-number}
 (either @samp{1} or @samp{2}), instead of the normal output.
 
-@zeroTerminatedOption
+@optZeroTerminated
 
 @end table
 
@@ -10329,11 +10341,7 @@ Suppress most error messages.
 @opindex --verbose
 Report error messages.
 
-@item -z
-@itemx --zero
-@opindex -z
-@opindex --zero
-Separate output items with NUL characters.
+@optZero
 
 @end table
 
@@ -11433,7 +11441,7 @@ The program accepts the following options.  Also see @ref{Common options}.
 
 @table @samp
 
-@optNull{du}
+@optNull
 
 @item -a
 @itemx --all
@@ -13223,11 +13231,7 @@ With this, an optional @var{suffix} must be specified using the
 Remove a trailing @var{suffix}.
 This option implies the @option{-a} option.
 
-@item -z
-@itemx --zero
-@opindex -z
-@opindex --zero
-Separate output items with NUL characters.
+@optZero
 
 @end table
 
@@ -13282,11 +13286,7 @@ The program accepts the following option.  Also see @ref{Common options}.
 
 @table @samp
 
-@item -z
-@itemx --zero
-@opindex -z
-@opindex --zero
-Separate output items with NUL characters.
+@optZero
 
 @end table
 
@@ -13619,23 +13619,6 @@ This is the default mode of operation.
 @opindex --quiet
 Suppress diagnostic messages for specified file names.
 
-@item -s
-@itemx --strip
-@itemx --no-symlinks
-@opindex -s
-@opindex --strip
-@opindex --no-symlinks
-Do not resolve symbolic links.  Only resolve references to
-@samp{/./}, @samp{/../} and remove extra @samp{/} characters.
-When combined with the @option{-m} option, realpath operates
-only on the file name, and does not touch any actual file.
-
-@item -z
-@itemx --zero
-@opindex -z
-@opindex --zero
-Separate output items with NUL characters.
-
 @item --relative-to=@var{file}
 @opindex --relative-to
 @cindex relpath
@@ -13664,6 +13647,19 @@ realpath --relative-base=/usr /tmp /usr/bin
 @result{} bin
 @end example
 
+@item -s
+@itemx --strip
+@itemx --no-symlinks
+@opindex -s
+@opindex --strip
+@opindex --no-symlinks
+Do not resolve symbolic links.  Only resolve references to
+@samp{/./}, @samp{/../} and remove extra @samp{/} characters.
+When combined with the @option{-m} option, realpath operates
+only on the file name, and does not touch any actual file.
+
+@optZero
+
 @end table
 
 @cindex exit status of @command{realpath}
@@ -14462,7 +14458,7 @@ The program accepts the following option.  Also see @ref{Common options}.
 
 @table @samp
 
-@optNull{printenv}
+@optNull
 
 @end table
 
@@ -16292,7 +16288,7 @@ Options must precede operands.
 
 @table @samp
 
-@optNull{env}
+@optNull
 
 @item -u @var{name}
 @itemx --unset=@var{name}
diff --git a/src/basename.c b/src/basename.c
index 05c5c7750..952153994 100644
--- a/src/basename.c
+++ b/src/basename.c
@@ -60,7 +60,7 @@ If specified, also remove a trailing SUFFIX.\n\
       fputs (_("\
   -a, --multiple       support multiple arguments and treat each as a NAME\n\
   -s, --suffix=SUFFIX  remove a trailing SUFFIX; implies -a\n\
-  -z, --zero           separate output with NUL rather than newline\n\
+  -z, --zero           end each output line with NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/dirname.c b/src/dirname.c
index fa9f87ec6..e0599a36a 100644
--- a/src/dirname.c
+++ b/src/dirname.c
@@ -57,7 +57,7 @@ removed; if NAME contains no /'s, output '.' (meaning the current directory).\n\
 \n\
 "), stdout);
       fputs (_("\
-  -z, --zero     separate output with NUL rather than newline\n\
+  -z, --zero     end each output line with NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/du.c b/src/du.c
index 890edb64c..e4509fd78 100644
--- a/src/du.c
+++ b/src/du.c
@@ -289,7 +289,7 @@ Summarize disk usage of each FILE, recursively for directories.\n\
       emit_mandatory_arg_note ();
 
       fputs (_("\
-  -0, --null            end each output line with 0 byte rather than newline\n\
+  -0, --null            end each output line with NUL, not newline\n\
   -a, --all             write counts for all files, not just directories\n\
       --apparent-size   print apparent sizes, rather than disk usage; although\
 \n\
diff --git a/src/env.c b/src/env.c
index 6a5c246a5..2b37d986e 100644
--- a/src/env.c
+++ b/src/env.c
@@ -60,7 +60,7 @@ Set each NAME to VALUE in the environment and run COMMAND.\n\
 
       fputs (_("\
   -i, --ignore-environment  start with an empty environment\n\
-  -0, --null           end each output line with 0 byte rather than newline\n\
+  -0, --null           end each output line with NUL, not newline\n\
   -u, --unset=NAME     remove variable from the environment\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
diff --git a/src/join.c b/src/join.c
index fd8f22c60..5c26e78aa 100644
--- a/src/join.c
+++ b/src/join.c
@@ -218,7 +218,7 @@ by whitespace.  When FILE1 or FILE2 (not both) is -, read standard input.\n\
                       print them without trying to pair them\n\
 "), stdout);
       fputs (_("\
-  -z, --zero-terminated     end lines with 0 byte, not newline\n\
+  -z, --zero-terminated     line delimiter is NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/printenv.c b/src/printenv.c
index f1e65940a..e1faeb5fd 100644
--- a/src/printenv.c
+++ b/src/printenv.c
@@ -67,7 +67,7 @@ If no VARIABLE is specified, print name and value pairs for them all.\n\
 "),
               program_name);
       fputs (_("\
-  -0, --null     end each output line with 0 byte rather than newline\n\
+  -0, --null     end each output line with NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/readlink.c b/src/readlink.c
index 5a4488726..d63f07b40 100644
--- a/src/readlink.c
+++ b/src/readlink.c
@@ -81,7 +81,7 @@ usage (int status)
   -q, --quiet,\n\
   -s, --silent                  suppress most error messages\n\
   -v, --verbose                 report error messages\n\
-  -z, --zero                    separate output with NUL rather than newline\n\
+  -z, --zero                    end each output line with NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/realpath.c b/src/realpath.c
index 4426572b0..0c5532710 100644
--- a/src/realpath.c
+++ b/src/realpath.c
@@ -83,7 +83,7 @@ all but the last component must exist\n\
       --relative-to=FILE       print the resolved path relative to FILE\n\
       --relative-base=FILE     print absolute paths unless paths below FILE\n\
   -s, --strip, --no-symlinks   don't expand symlinks\n\
-  -z, --zero                   separate output with NUL rather than newline\n\
+  -z, --zero                   end each output line with NUL, not newline\n\
 \n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
diff --git a/src/shuf.c b/src/shuf.c
index 6ae075549..915f7b7a5 100644
--- a/src/shuf.c
+++ b/src/shuf.c
@@ -77,7 +77,9 @@ Write a random permutation of the input lines to standard output.\n\
   -o, --output=FILE         write result to FILE instead of standard output\n\
       --random-source=FILE  get random bytes from FILE\n\
   -r, --repeat              output lines can be repeated\n\
-  -z, --zero-terminated     end lines with 0 byte, not newline\n\
+"), stdout);
+      fputs (_("\
+  -z, --zero-terminated     line delimiter is NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/sort.c b/src/sort.c
index 3380be6c5..49caae525 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -504,7 +504,7 @@ Other options:\n\
 \n\
 "), DEFAULT_TMPDIR);
       fputs (_("\
-  -z, --zero-terminated     end lines with 0 byte, not newline\n\
+  -z, --zero-terminated     line delimiter is NUL, not newline\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
diff --git a/src/stty.c b/src/stty.c
index 7bb3f5121..3c4857865 100644
--- a/src/stty.c
+++ b/src/stty.c
@@ -634,7 +634,7 @@ Output settings:\n\
 "), stdout);
       fputs (_("\
  * [-]ocrnl      translate carriage return to newline\n\
- * [-]ofdel      use delete characters for fill instead of null characters\n\
+ * [-]ofdel      use delete characters for fill instead of NUL characters\n\
  * [-]ofill      use fill (padding) characters instead of timing for delays\n\
  * [-]olcuc      translate lowercase characters to uppercase\n\
  * [-]onlcr      translate newline to carriage return-newline\n\
diff --git a/src/uniq.c b/src/uniq.c
index deba0a3d7..54200ff45 100644
--- a/src/uniq.c
+++ b/src/uniq.c
@@ -200,7 +200,9 @@ With no options, matching lines are merged to the first occurrence.\n\
   -i, --ignore-case     ignore differences in case when comparing\n\
   -s, --skip-chars=N    avoid comparing the first N characters\n\
   -u, --unique          only print unique lines\n\
-  -z, --zero-terminated  end lines with 0 byte, not newline\n\
+"), stdout);
+      fputs (_("\
+  -z, --zero-terminated     line delimiter is NUL, not newline\n\
 "), stdout);
      fputs (_("\
   -w, --check-chars=N   compare no more than N characters in lines\n\