2006-04-22  Jerry DeLisle  <jvdelisle@gcc.gnu.org>

	PR libgfortran/20257
	* io/io.h: Add prototypes for get_internal_unit and free_internal_unit.
	* io/unit.c (get_internal_unit): Initialize unit number, not zero.
	(free_internal_unit): New function to consolidate freeing memory.
	(get_unit): Initialize internal_unit_desc to NULL when unit is
	external.
	* io/unix.c (mem_close): Check for not NULL before freeing memory.
	* io/transfer.c (read_block): Reset bytes_left and skip error if unit
	is preconnected and default record length is reached.
	(read_block_direct): Ditto.
	(write_block): Ditto.
	(write_buf): Ditto.
	(data_transfer_init): Only flush if not internal unit.
	(finalize_transfer): Ditto and delete code to free memory used by
	internal units.
	(st_read_done): Use new function - free_internal_unit.
	(st_write_done): Use new function - free_internal unit.

From-SVN: r113190