Converts a file identifier into a virtual node (v-node).
int vfs_vget (vfsp, vpp, fidp, crp) struct vfs *vfsp; struct vnode **vpp; struct fileid *fidp; struct ucred *crp;
| vfsp | Points to the virtual file system that is to contain the v-node. Any returned v-node should belong to this virtual file system. | ||||||
| vpp | Points to the place to return the v-node pointer. This is set to point to the new v-node. The fields in this v-node should be set as follows:
| ||||||
| fidp | Points to a file identifier. This is a file system-specific file identifier that must conform to the fileid structure.
Note: If the fidp parameter is invalid, the vpp parameter should be set to a null value by the vfs_vget entry point. | ||||||
| crp | Points to the cred structure. This structure contains data that the file system can use to validate access permission. |
The vfs_vget entry point is called to convert a file identifier into a v-node. This entry point uses information in the vfsp and fidp parameters to create a v-node or attach to an existing v-node. This v-node represents, logically, the same file system object as the file identified by the fidp parameter.
If the v-node already exists, successful operation of this entry point increments the v-node use count and returns a pointer to the v-node. If the v-node does not exist, the vfs_vget entry point creates it using the vn_get kernel service and returns a pointer to the new v-node.
The vfs_vget entry point can be called from the process environment only.
| 0 | Indicates success. |
Nonzero return values are returned from the /usr/include/sys/errno.h file to indicate failure. A typical value includes:
| EINVAL | Indicates that the remote virtual file system specified by the vfsp parameter does not support chained mounts. |
The vn_get kernel service.
The access subroutine.
Virtual File System Overview, Virtual File System Kernel Extensions Overview, Logical File System Overview, Understanding Virtual Nodes (V-nodes) in AIX Kernel Extensions and Device Support Programming Concepts.