+* New command line option `--warning'
+
+The `--warning' command line option allows to suppress or enable
+particular warning messages during `tar' run. It takes a single
+argument (a `keyword'), identifying the class of warning messages
+to affect. If the argument is prefixed with `no-', such warning
+messages are suppressed. For example,
+
+ tar --warning=no-alone-zero-block -x -f archive
+
+suppresses the output of `A lone zero block' diagnostics, which is
+normally issued if `archive' ends with a single block of zeros.
+