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Vattach/vfatch

int32 Vattach(int32 file_id, int32 vgroup_ref, char *access)
file_id

IN:

File identifier returned by Hopen

vgroup_ref

IN:

Reference number for the vgroup to open

access

IN:

Type of access - "r" for read, "w" for write.

Purpose

Attaches to an existing vgroup or creates a new vgroup and returns an identifier for it.

Return value

Returns a vgroup identifier if successful and FAIL (or -1) otherwise.

Description

The file_id is the file identifier of an opened HDF file. The vgroup_ref parameter specifies which vgroup in the HDF file to attach to: if vgroup_ref = -1, a new vgroup is created. if vgroup_ref is positive, the vgroup corresponding to the vgroup_ref is attached. Vattach returns a vgroup identifier for the accessed vgroup. This identifier or vgroup_id, is used for all further operations on the vgroup. Once operations are complete, the vgroup_id must be disposed of via a call to Vdetach. Multiple attaches may be made to the same vgroup simultaneously, giving rise to several vgroup identifiers for the same vgroup. Each vgroup_id must be disposed of independently.

FORTRAN

integer function vfatch(file_id, vgroup_ref, access)

integer file_id, vgroup_ref

character access



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hdfhelp@ncsa.uiuc.edu
HDF User's Reference Manual, Draft 06/09/97, NCSA HDF Development Group.