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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | BUGS | SEE ALSO | COLOPHON |
FANOTIFY_MARK(2) Linux Programmer's Manual FANOTIFY_MARK(2)
fanotify_mark - add, remove, or modify an fanotify mark on a filesys‐
tem object
#include <sys/fanotify.h>
int fanotify_mark(int fanotify_fd, unsigned int flags,
uint64_t mask, int dirfd, const char *pathname);
For an overview of the fanotify API, see fanotify(7).
fanotify_mark() adds, removes, or modifies an fanotify mark on a
filesystem object. The caller must have read permission on the
filesystem object that is to be marked.
The fanotify_fd argument is a file descriptor returned by
fanotify_init(2).
flags is a bit mask describing the modification to perform. It must
include exactly one of the following values:
FAN_MARK_ADD
The events in mask will be added to the mark mask (or to the
ignore mask). mask must be nonempty or the error EINVAL will
occur.
FAN_MARK_REMOVE
The events in argument mask will be removed from the mark mask
(or from the ignore mask). mask must be nonempty or the error
EINVAL will occur.
FAN_MARK_FLUSH
Remove either all mount or all non-mount marks from the
fanotify group. If flags contains FAN_MARK_MOUNT, all marks
for mounts are removed from the group. Otherwise, all marks
for directories and files are removed. No flag other than
FAN_MARK_MOUNT can be used in conjunction with FAN_MARK_FLUSH.
mask is ignored.
If none of the values above is specified, or more than one is
specified, the call fails with the error EINVAL.
In addition, zero or more of the following values may be ORed into
flags:
FAN_MARK_DONT_FOLLOW
If pathname is a symbolic link, mark the link itself, rather
than the file to which it refers. (By default,
fanotify_mark() dereferences pathname if it is a symbolic
link.)
FAN_MARK_ONLYDIR
If the filesystem object to be marked is not a directory, the
error ENOTDIR shall be raised.
FAN_MARK_MOUNT
Mark the mount point specified by pathname. If pathname is
not itself a mount point, the mount point containing pathname
will be marked. All directories, subdirectories, and the
contained files of the mount point will be monitored.
FAN_MARK_IGNORED_MASK
The events in mask shall be added to or removed from the
ignore mask.
FAN_MARK_IGNORED_SURV_MODIFY
The ignore mask shall survive modify events. If this flag is
not set, the ignore mask is cleared when a modify event occurs
for the ignored file or directory.
mask defines which events shall be listened for (or which shall be
ignored). It is a bit mask composed of the following values:
FAN_ACCESS
Create an event when a file or directory (but see BUGS) is
accessed (read).
FAN_MODIFY
Create an event when a file is modified (write).
FAN_CLOSE_WRITE
Create an event when a writable file is closed.
FAN_CLOSE_NOWRITE
Create an event when a read-only file or directory is closed.
FAN_OPEN
Create an event when a file or directory is opened.
FAN_Q_OVERFLOW
Create an event when an overflow of the event queue occurs.
The size of the event queue is limited to 16384 entries if
FAN_UNLIMITED_QUEUE is not set in fanotify_init(2).
FAN_OPEN_PERM
Create an event when a permission to open a file or directory
is requested. An fanotify file descriptor created with
FAN_CLASS_PRE_CONTENT or FAN_CLASS_CONTENT is required.
FAN_ACCESS_PERM
Create an event when a permission to read a file or directory
is requested. An fanotify file descriptor created with
FAN_CLASS_PRE_CONTENT or FAN_CLASS_CONTENT is required.
FAN_ONDIR
Create events for directories—for example, when opendir(3),
readdir(3) (but see BUGS), and closedir(3) are called.
Without this flag, only events for files are created.
FAN_EVENT_ON_CHILD
Events for the immediate children of marked directories shall
be created. The flag has no effect when marking mounts. Note
that events are not generated for children of the
subdirectories of marked directories. To monitor complete
directory trees it is necessary to mark the relevant mount.
The following composed value is defined:
FAN_CLOSE
A file is closed (FAN_CLOSE_WRITE|FAN_CLOSE_NOWRITE).
The filesystem object to be marked is determined by the file
descriptor dirfd and the pathname specified in pathname:
* If pathname is NULL, dirfd defines the filesystem object to be
marked.
* If pathname is NULL, and dirfd takes the special value AT_FDCWD,
the current working directory is to be marked.
* If pathname is absolute, it defines the filesystem object to be
marked, and dirfd is ignored.
* If pathname is relative, and dirfd does not have the value
AT_FDCWD, then the filesystem object to be marked is determined by
interpreting pathname relative the directory referred to by dirfd.
* If pathname is relative, and dirfd has the value AT_FDCWD, then
the filesystem object to be marked is determined by interpreting
pathname relative the current working directory.
On success, fanotify_mark() returns 0. On error, -1 is returned, and
errno is set to indicate the error.
EBADF An invalid file descriptor was passed in fanotify_fd.
EINVAL An invalid value was passed in flags or mask, or fanotify_fd
was not an fanotify file descriptor.
EINVAL The fanotify file descriptor was opened with FAN_CLASS_NOTIF
and mask contains a flag for permission events (FAN_OPEN_PERM
or FAN_ACCESS_PERM).
ENOENT The filesystem object indicated by dirfd and pathname does not
exist. This error also occurs when trying to remove a mark
from an object which is not marked.
ENOMEM The necessary memory could not be allocated.
ENOSPC The number of marks exceeds the limit of 8192 and the
FAN_UNLIMITED_MARKS flag was not specified when the fanotify
file descriptor was created with fanotify_init(2).
ENOSYS This kernel does not implement fanotify_mark(). The fanotify
API is available only if the kernel was configured with
CONFIG_FANOTIFY.
ENOTDIR
flags contains FAN_MARK_ONLYDIR, and dirfd and pathname do not
specify a directory.
fanotify_mark() was introduced in version 2.6.36 of the Linux kernel
and enabled in version 2.6.37.
This system call is Linux-specific.
The following bugs were present in Linux kernels before version 3.16:
* If flags contains FAN_MARK_FLUSH, dirfd and pathname must specify
a valid filesystem object, even though this object is not used.
* readdir(2) does not generate a FAN_ACCESS event.
* If fanotify_mark() is called with FAN_MARK_FLUSH, flags is not
checked for invalid values.
fanotify_init(2), fanotify(7)
This page is part of release 4.12 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
Linux 2016-10-08 FANOTIFY_MARK(2)
Pages that refer to this page: fanotify_init(2), open(2), syscalls(2), proc(5), fanotify(7)