VOP_IOCTL(9) BSD Kernel Developer's Manual VOP_IOCTL(9)NAME
VOP_IOCTL -- device specific control
SYNOPSIS
#include <sys/param.h>
#include <sys/vnode.h>
int
VOP_IOCTL(struct vnode *vp, u_long command, caddr_t data, int fflag, struct ucred *cred, struct thread *td);
DESCRIPTION
Manipulate a file in device dependent ways.
Its arguments are:
vp The vnode of the file (normally representing a device).
command The device specific operation to perform.
data Extra data for the specified operation.
fflag Some flags ???
cred The caller's credentials.
td The calling thread.
Most file systems do not implement this entry point.
LOCKS
The file should not be locked on entry.
RETURN VALUES
If successful, zero is returned, otherwise an appropriate error code.
If the ioctl is not recognized or not handled, ENOTTY should be returned.
SEE ALSO vnode(9)AUTHORS
This manual page was written by Doug Rabson.
BSD July 24, 1996 BSD
Check Out this Related Man Page
VOP_ACCESS(9) BSD Kernel Developer's Manual VOP_ACCESS(9)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.
BSD September 18, 2009 BSD
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