int inotify_add_watch(int fd, const char *pathname, uint32_t mask);
DESCRIPTION
inotify_add_watch()
adds a new watch, or modifies an existing watch,
for the file whose location is specified in
pathname;
the caller must have read permission for this file.
The
fd
argument is a file descriptor referring to the
inotify instance whose watch list is to be modified.
The events to be monitored for
pathname
are specified in the
mask
bit-mask argument.
See
inotify(7)
for a description of the bits that can be set in
mask.
A successful call to
inotify_add_watch()
returns the unique watch descriptor associated with
pathname
for this inotify instance.
If
pathname
was not previously being watched by this inotify instance,
then the watch descriptor is newly allocated.
If
pathname
was already being watched, then the descriptor
for the existing watch is returned.
The watch descriptor is returned by later
read(2)s
from the inotify file descriptor.
These reads fetch
inotify_event
structures (see
inotify(7))
indicating file system events;
the watch descriptor inside this structure identifies
the object for which the event occurred.
RETURN VALUE
On success,
inotify_add_watch()
returns a non-negative watch descriptor.
On error -1 is returned and
errno
is set appropriately.
ERRORS
EACCES
Read access to the given file is not permitted.
EBADF
The given file descriptor is not valid.
EFAULT
pathname
points outside of the process's accessible address space.
EINVAL
The given event mask contains no valid events; or
fd
is not an inotify file descriptor.
ENOMEM
Insufficient kernel memory was available.
ENOSPC
The user limit on the total number of inotify watches was reached or the
kernel failed to allocate a needed resource.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
