Signature:

      SUBROUTINE h5oopen_f(loc_id, name, obj_id, hdferr, lapl_id)
        IMPLICIT NONE
        INTEGER(HID_T)  , INTENT(IN)  :: loc_id
        CHARACTER(LEN=*), INTENT(IN)  :: name
        INTEGER(HID_T)  , INTENT(OUT) :: obj_id
        INTEGER         , INTENT(OUT) :: hdferr
        INTEGER(HID_T)  , INTENT(IN), OPTIONAL :: lapl_id

Inputs:

      loc_id  - File or group identifier.
      name    - Path to the object, relative to loc_id.

Outputs:

      obj_id  - Object identifier for the opened object.
      hdferr  - Returns 0 if successful and -1 if fails.

Optional parameters:

      lapl_id - Access property list identifier for the
                link pointing to the object.