-@file{/tmp} except the file @file{/tmp/foo}, you can use the command
-@samp{tar --create --file=arch.tar --exclude=foo}. You may give
-multiple @samp{--exclude} options.
+the working directory except for files whose names end in @file{.o}, you
+can use the command @samp{tar -cf arch.tar --exclude='*.o' .}.
+
+A @var{pattern} containing @samp{/} excludes a file if an initial prefix
+of the file name matches @var{pattern}; a @var{pattern} without @samp{/}
+excludes a file if it matches any of its file name components. For
+example, the pattern @samp{b*/RCS} excludes @file{blob/RCS} and
+@file{blob/RCS/f} but not @file{a/blob/RCS} or @file{blob/sub/RCS},
+whereas the pattern @samp{RCS} excludes all these file names.
+
+You may give multiple @samp{--exclude} options.