1FANOTIFY_MARK(2) Linux Programmer's Manual FANOTIFY_MARK(2)
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6 fanotify_mark - add, remove, or modify an fanotify mark on a filesystem
7 object
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10 #include <sys/fanotify.h>
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12 int fanotify_mark(int fanotify_fd, unsigned int flags,
13 uint64_t mask, int dirfd, const char *pathname);
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16 For an overview of the fanotify API, see fanotify(7).
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18 fanotify_mark() adds, removes, or modifies an fanotify mark on a
19 filesystem object. The caller must have read permission on the
20 filesystem object that is to be marked.
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22 The fanotify_fd argument is a file descriptor returned by fan‐
23 otify_init(2).
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25 flags is a bit mask describing the modification to perform. It must
26 include exactly one of the following values:
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28 FAN_MARK_ADD
29 The events in mask will be added to the mark mask (or to the
30 ignore mask). mask must be nonempty or the error EINVAL will
31 occur.
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33 FAN_MARK_REMOVE
34 The events in argument mask will be removed from the mark mask
35 (or from the ignore mask). mask must be nonempty or the error
36 EINVAL will occur.
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38 FAN_MARK_FLUSH
39 Remove either all mount or all non-mount marks from the fanotify
40 group. If flags contains FAN_MARK_MOUNT, all marks for mounts
41 are removed from the group. Otherwise, all marks for directo‐
42 ries and files are removed. No flag other than FAN_MARK_MOUNT
43 can be used in conjunction with FAN_MARK_FLUSH. mask is
44 ignored.
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46 If none of the values above is specified, or more than one is speci‐
47 fied, the call fails with the error EINVAL.
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49 In addition, zero or more of the following values may be ORed into
50 flags:
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52 FAN_MARK_DONT_FOLLOW
53 If pathname is a symbolic link, mark the link itself, rather
54 than the file to which it refers. (By default, fanotify_mark()
55 dereferences pathname if it is a symbolic link.)
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57 FAN_MARK_ONLYDIR
58 If the filesystem object to be marked is not a directory, the
59 error ENOTDIR shall be raised.
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61 FAN_MARK_MOUNT
62 Mark the mount point specified by pathname. If pathname is not
63 itself a mount point, the mount point containing pathname will
64 be marked. All directories, subdirectories, and the contained
65 files of the mount point will be monitored.
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67 FAN_MARK_IGNORED_MASK
68 The events in mask shall be added to or removed from the ignore
69 mask.
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71 FAN_MARK_IGNORED_SURV_MODIFY
72 The ignore mask shall survive modify events. If this flag is
73 not set, the ignore mask is cleared when a modify event occurs
74 for the ignored file or directory.
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76 mask defines which events shall be listened for (or which shall be
77 ignored). It is a bit mask composed of the following values:
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79 FAN_ACCESS
80 Create an event when a file or directory (but see BUGS) is
81 accessed (read).
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83 FAN_MODIFY
84 Create an event when a file is modified (write).
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86 FAN_CLOSE_WRITE
87 Create an event when a writable file is closed.
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89 FAN_CLOSE_NOWRITE
90 Create an event when a read-only file or directory is closed.
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92 FAN_OPEN
93 Create an event when a file or directory is opened.
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95 FAN_Q_OVERFLOW
96 Create an event when an overflow of the event queue occurs. The
97 size of the event queue is limited to 16384 entries if
98 FAN_UNLIMITED_QUEUE is not set in fanotify_init(2).
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100 FAN_OPEN_PERM
101 Create an event when a permission to open a file or directory is
102 requested. An fanotify file descriptor created with
103 FAN_CLASS_PRE_CONTENT or FAN_CLASS_CONTENT is required.
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105 FAN_ACCESS_PERM
106 Create an event when a permission to read a file or directory is
107 requested. An fanotify file descriptor created with
108 FAN_CLASS_PRE_CONTENT or FAN_CLASS_CONTENT is required.
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110 FAN_ONDIR
111 Create events for directories—for example, when opendir(3),
112 readdir(3) (but see BUGS), and closedir(3) are called. Without
113 this flag, only events for files are created.
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115 FAN_EVENT_ON_CHILD
116 Events for the immediate children of marked directories shall be
117 created. The flag has no effect when marking mounts. Note that
118 events are not generated for children of the subdirectories of
119 marked directories. To monitor complete directory trees it is
120 necessary to mark the relevant mount.
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122 The following composed value is defined:
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124 FAN_CLOSE
125 A file is closed (FAN_CLOSE_WRITE|FAN_CLOSE_NOWRITE).
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127 The filesystem object to be marked is determined by the file descriptor
128 dirfd and the pathname specified in pathname:
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130 * If pathname is NULL, dirfd defines the filesystem object to be
131 marked.
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133 * If pathname is NULL, and dirfd takes the special value AT_FDCWD, the
134 current working directory is to be marked.
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136 * If pathname is absolute, it defines the filesystem object to be
137 marked, and dirfd is ignored.
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139 * If pathname is relative, and dirfd does not have the value AT_FDCWD,
140 then the filesystem object to be marked is determined by interpret‐
141 ing pathname relative the directory referred to by dirfd.
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143 * If pathname is relative, and dirfd has the value AT_FDCWD, then the
144 filesystem object to be marked is determined by interpreting path‐
145 name relative the current working directory.
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148 On success, fanotify_mark() returns 0. On error, -1 is returned, and
149 errno is set to indicate the error.
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152 EBADF An invalid file descriptor was passed in fanotify_fd.
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154 EINVAL An invalid value was passed in flags or mask, or fanotify_fd was
155 not an fanotify file descriptor.
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157 EINVAL The fanotify file descriptor was opened with FAN_CLASS_NOTIF and
158 mask contains a flag for permission events (FAN_OPEN_PERM or
159 FAN_ACCESS_PERM).
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161 ENOENT The filesystem object indicated by dirfd and pathname does not
162 exist. This error also occurs when trying to remove a mark from
163 an object which is not marked.
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165 ENOMEM The necessary memory could not be allocated.
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167 ENOSPC The number of marks exceeds the limit of 8192 and the FAN_UNLIM‐
168 ITED_MARKS flag was not specified when the fanotify file
169 descriptor was created with fanotify_init(2).
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171 ENOSYS This kernel does not implement fanotify_mark(). The fanotify
172 API is available only if the kernel was configured with CON‐
173 FIG_FANOTIFY.
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175 ENOTDIR
176 flags contains FAN_MARK_ONLYDIR, and dirfd and pathname do not
177 specify a directory.
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180 fanotify_mark() was introduced in version 2.6.36 of the Linux kernel
181 and enabled in version 2.6.37.
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184 This system call is Linux-specific.
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187 The following bugs were present in Linux kernels before version 3.16:
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189 * If flags contains FAN_MARK_FLUSH, dirfd and pathname must specify a
190 valid filesystem object, even though this object is not used.
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192 * readdir(2) does not generate a FAN_ACCESS event.
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194 * If fanotify_mark() is called with FAN_MARK_FLUSH, flags is not
195 checked for invalid values.
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198 fanotify_init(2), fanotify(7)
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201 This page is part of release 4.15 of the Linux man-pages project. A
202 description of the project, information about reporting bugs, and the
203 latest version of this page, can be found at
204 https://www.kernel.org/doc/man-pages/.
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208Linux 2016-10-08 FANOTIFY_MARK(2)