INOTIFY_ADD_WATCH(2)					     Linux Programmer's Manual					      INOTIFY_ADD_WATCH(2)

NAME

       inotify_add_watch - add a watch to an initialized inotify instance

SYNOPSIS

       #include <sys/inotify.h>

       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 modi-
       fied.   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  path-
       name  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  ino-
       tify(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 nonnegative 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.

       ENOENT A directory component in pathname does not exist or is a dangling symbolic link.

       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.

VERSIONS

       Inotify was merged into the 2.6.13 Linux kernel.

CONFORMING TO

       This system call is Linux-specific.

SEE ALSO

       inotify_init(2), inotify_rm_watch(2), inotify(7)

COLOPHON

       This  page is part of release 3.53 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								    2010-10-20						      INOTIFY_ADD_WATCH(2)