NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | SEE ALSO | COLOPHON
INOTIFY_ADD_WATCH(2) Linux Programmer's Manual INOTIFY_ADD_WATCH(2)
inotify_add_watch - add a watch to an initialized inotify instance
#include <sys/inotify.h>
int inotify_add_watch(int fd, const char *pathname, uint32_t mask);
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.
On success, inotify_add_watch() returns a non-negative watch descriptor. On
error -1 is returned and errno is set appropriately.
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.
Inotify was merged into the 2.6.13 Linux kernel.
This system call is Linux-specific.
inotify_init(2), inotify_rm_watch(2), inotify(7)
This page is part of release 3.23 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/.
Linux 2006-02-07 INOTIFY_ADD_WATCH(2)