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NBS_GET_MODIFIED_POINTER - Get a pointer to the noticeboard modified count or an item modified count depending on whether this is a structured or primitive item

Description:
Check that the ID is not NIL.
If the item is structured get the noticeboard modified count.
If the item is primitive get the item's modified count.
Return a pointer to the appropriate modified count.

For structured items, this value is incremented each time an item in the noticeboard is updated.

For primitive items, if this value is even then the associated values are not currently being updated. If it is odd then they are currently being updated. The total number of updates to this item is half the value of the modified count.

An "update" is an update of an item's value, shape or size.

Note that when item data is accessed directly via pointer then the modified count is not updated unless this is done explicitly using the NBS_INC_MODIFIED routine.


Invocation:
(Int) = NBS_GET_MODIFIED_POINTER (ID,POINTER,STATUS)

Arguments:

ID = INTEGER (Given)
Identifier of the item for which the pointer to its modified count is to be got.
POINTER = INTEGER (Returned)
The address of the item's modified count.
STATUS = INTEGER (Given and returned)
The global status. Possible return values are,

NBS__NILID   		 NIL ID 




next up previous 372
Next: NBS_GET_UPDATED - Determine whether a primitive item or the noticeboard has been updated since the noticeboard was found or this
Up: Description of Individual NBS Routines
Previous: NBS_GET_MODIFIED - Get the noticeboard modified count or an item modified count depending on whether this is a structured or

NBS The Noticeboard System
Starlink User Note 77
D.J. Allan
11 September 1995
E-mail:ussc@star.rl.ac.uk