next up previous
Next: More Advanced Use: Partitioning
Up: NDF SECTIONS
Previous: Restrictions on the Use of Sections

Restrictions on Mapped Access to Sections  

The restrictions described in §[*] concerning multiple mapped access to NDF array components also apply to NDF sections if there is a possibility of an access conflict occurring. Thus, if two NDF sections refer to the same base NDF, and the regions to which they refer (more precisely their transfer windows) intersect, then only one of these sections may be mapped at any time for write or update access to the same array component.

If necessary, an application can determine if such a conflict may occur by using the routine NDF_SAME. For instance:

      LOGICAL SAME, ISECT

      ...

      CALL NDF_SAME( INDF1, INDF2, SAME, ISECT, STATUS )

will return a .TRUE. value via the SAME argument if the two NDF identifiers supplied refer to the same base NDF, and will also return a .TRUE. result via the ISECT argument if their transfer windows intersect.



next up previous
Next: More Advanced Use: Partitioning
Up: NDF SECTIONS
Previous: Restrictions on the Use of Sections


Starlink User Note 33
R.F. Warren-Smith
11th January 2000
E-mail:rfws@star.rl.ac.uk

Copyright © 2000 Council for the Central Laboratory of the Research Councils