[patch] documentation bug in tail: no mention of -n +N syntax

[Evan Hunt]

I was bitten this evening by the fact that the old "tail +N" syntax--in
other owrds, "omit the first N lines of the file, then show the rest"--has
been deprecated.  (That was an unforunate decision on POSIX's part, IMHO,
but I see it's already been discussed at length on this list, so nevermind).

In trying to figure out how to fix my script, I checked "tail --help" and
"man tail", and there was no mention of the fact that tail even *has* this
ability anymore.  Eventually I dug up the "tail -n +N" option on a web
page, and that worked.

So the patch below clarifies the documentation.

Evan Hunt

===================================================
diff -u tail.c.00 tail.c
--- tail.c.00   2006-12-15 22:34:58.000000000 -0800
+++ tail.c      2006-12-16 00:07:00.000000000 -0800
@@ -231,7 +231,9 @@
                            inaccessible when tail starts or if it becomes\n\
                            inaccessible later; useful when following by 
name,\n\
                            i.e., with --follow=name\n\
-  -c, --bytes=N            output the last N bytes\n\
+  -c, --bytes=N            if N is preceded by no sign or a '-', output the\n\
+                           last N bytes; if it is preceded by a '+', output\n\
+                           all bytes after the first N\n\
 "), stdout);
      fputs (_("\
   -f, --follow[={name|descriptor}]\n\
@@ -241,7 +243,9 @@
   -F                       same as --follow=name --retry\n\
 "), stdout);
      printf (_("\
-  -n, --lines=N            output the last N lines, instead of the last %d\n\
+  -n, --lines=N            if N is preceded by no sign or a '-', output the\n\
+                           last N lines (default %d); if it is preceded by\n\
+                           a '+', output all lines after the first N.\n\
       --max-unchanged-stats=N\n\
                            with --follow=name, reopen a FILE which has not\n\
                            changed size after N (default %d) iterations\n\