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.