NAME
VOP_ACCESS,
VOP_ACCESSX —
check access permissions of a file or
Unix domain socket
SYNOPSIS
#include
<sys/param.h>
#include <sys/vnode.h>
int
VOP_ACCESS(struct
vnode *vp, accmode_t
accmode, struct ucred
*cred, struct thread
*td);
int
VOP_ACCESSX(struct
vnode *vp, accmode_t
accmode, struct ucred
*cred, struct thread
*td);
DESCRIPTION
This entry point checks the access permissions of the file against the given credentials.Its arguments are:
- vp
- The vnode of the file to check.
- accmode
- The type of access required.
- cred
- The user credentials to check.
- td
- The thread which is checking.
The accmode is a mask which
can contain flags described in <sys/vnode.h>, e.g.
VREAD, VWRITE or
VEXEC. For
VOP_ACCESS(),
the only flags that may be set in accmode are
VEXEC, VWRITE,
VREAD, VADMIN and
VAPPEND. To check for other flags, one has to use
VOP_ACCESSX()
instead.
LOCKS
The vnode will be locked on entry and should remain locked on return.
RETURN VALUES
If the file is accessible in the specified way, then zero is returned, otherwise an appropriate error code is returned.
ERRORS
- [
EPERM] - An attempt was made to change an immutable file.
- [
EACCES] - The permission bits the file mode or the ACL do not permit the requested access.
SEE ALSO
vaccess(9), vaccess_acl_nfs4(9), vaccess_acl_posix1e(9), vnode(9)
AUTHORS
This manual page was written by Doug Rabson.