doc: tty: mention the removal of the -s option from POSIX

* doc/coreutils.texi (tty invocation): Mention that POSIX.1-2001 removed
the -s option and that portable scripts can redirect standard out to
/dev/null instead.

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index acbb5454a2d38a24cd60ca5e92e2891be30f63ee..5fe87ace5c49b0b4f095cdaa9a64b1911072098e 100644 (file)
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -15403,6 +15403,8 @@ The program accepts the following option.  Also see @ref{Common options}.
 @optItemx{tty,--quiet,}
 Print nothing; only return an exit status.
 
+POSIX.1-2001 removed the @option{-s} option.  Portable shell scripts
+should redirect standard output to @file{/dev/null} instead.
 @end table
 
 @cindex exit status of @command{tty}