Name: H5Lis_registered
Signature:
  htri_t `H5Lis_registered`( H5L_type_t `link_cls_id` )

Purpose:
  Determines whether a class of user-defined links is registered.

Description:
  `H5Lis_registered` tests whether a user-defined link class is currently registered, either by the HDF5 Library or by the user through the use of `H5Lregister`.

  A link class must be registered to create new links of that type or to traverse exisitng links of that type.

Parameters:

  H5L_type_t `link_cls_id` | IN: User-defined link class identifier

Returns:
  Returns a positive value if the link class has been registered and zero if it is unregistered. Otherwise returns a negative value; this may mean that the identifier is not a valid user-defined class identifier.

Fortran90 Interface: H5Lis_registered_f

      SUBROUTINE H5Lis_registered_f(link_cls_id, registered, hdferr)
        IMPLICIT NONE
        INTEGER, INTENT(IN) :: link_cls_id  ! User-defined link class identifier
        LOGICAL, INTENT(OUT) :: registered  ! .TRUE.  - if the link class is registered
                                            ! .FALSE. - if it is unregistered
        INTEGER, INTENT(OUT) :: hdferr      ! Error code:
                                            ! 0 on success and -1 on failure
      END SUBROUTINE H5Lis_registered_f

History:

  Release | C
  1.8.0 | Function introduced in this release.