t/lib/io_const.t See if constants from IO work
t/lib/io_dir.t See if directory-related methods from IO work
t/lib/io_dup.t See if dup()-related methods from IO work
+t/lib/io_linenum.t See if I/O line numbers are tracked correctly
t/lib/io_multihomed.t See if INET sockets work with multi-homed hosts
t/lib/io_pipe.t See if pipe()-related methods from IO work
t/lib/io_poll.t See if poll()-related methods from IO work