#! stap -p2

probe foo.a = kernel.function("sys_read") /* some */ ! /* sufficient */ ,
              kernel.function("no_such_function")
      { "foo.a" }

probe foo.b = module("*scsi*").function("no_such_thing") /* none */ ? ,
      	      module("*scsi*").function("*queue*") /* some */ ! , /* suff'nt */
	      module("no_such_module").function("no_such_function") 
      { "foo.b" }
probe foo.* { }