1GETXATTR(2) Linux Programmer's Manual GETXATTR(2)
2
6 getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value
7
9 #include <sys/xattr.h>
10 ssize_t getxattr(const char *path, const char *name,
12 void *value, size_t size);
13 ssize_t lgetxattr(const char *path, const char *name,
14 void *value, size_t size);
15 ssize_t fgetxattr(int fd, const char *name,
16 void *value, size_t size);
17
19 Extended attributes are name:value pairs associated with inodes (files,
20 directories, symbolic links, etc.). They are extensions to the normal
21 attributes which are associated with all inodes in the system (i.e.,
22 the stat(2) data). A complete overview of extended attributes concepts
23 can be found in xattr(7).
24 getxattr() retrieves the value of the extended attribute identified by
26 name and associated with the given path in the filesystem. The attri‐
27 bute value is placed in the buffer pointed to by value; size specifies
28 the size of that buffer. The return value of the call is the number of
29 bytes placed in value.
30 lgetxattr() is identical to getxattr(), except in the case of a sym‐
32 bolic link, where the link itself is interrogated, not the file that it
33 refers to.
34 fgetxattr() is identical to getxattr(), only the open file referred to
36 by fd (as returned by open(2)) is interrogated in place of path.
37 An extended attribute name is a null-terminated string. The name in‐
39 cludes a namespace prefix; there may be several, disjoint namespaces
40 associated with an individual inode. The value of an extended attri‐
41 bute is a chunk of arbitrary textual or binary data that was assigned
42 using setxattr(2).
43 If size is specified as zero, these calls return the current size of
45 the named extended attribute (and leave value unchanged). This can be
46 used to determine the size of the buffer that should be supplied in a
47 subsequent call. (But, bear in mind that there is a possibility that
48 the attribute value may change between the two calls, so that it is
49 still necessary to check the return status from the second call.)
50
52 On success, these calls return a nonnegative value which is the size
53 (in bytes) of the extended attribute value. On failure, -1 is returned
54 and errno is set to indicate the error.
55
57 E2BIG The size of the attribute value is larger than the maximum size
58 allowed; the attribute cannot be retrieved. This can happen on
59 filesystems that support very large attribute values such as
60 NFSv4, for example.
61 ENODATA
63 The named attribute does not exist, or the process has no access
64 to this attribute.
65 ENOTSUP
67 Extended attributes are not supported by the filesystem, or are
68 disabled.
69 ERANGE The size of the value buffer is too small to hold the result.
71 In addition, the errors documented in stat(2) can also occur.
73
75 These system calls have been available on Linux since kernel 2.4; glibc
76 support is provided since version 2.3.
77
79 These system calls are Linux-specific.
80
82 See listxattr(2).
83
85 getfattr(1), setfattr(1), listxattr(2), open(2), removexattr(2), setx‐
86 attr(2), stat(2), symlink(7), xattr(7)
87
89 This page is part of release 5.13 of the Linux man-pages project. A
90 description of the project, information about reporting bugs, and the
91 latest version of this page, can be found at
92 https://www.kernel.org/doc/man-pages/.
93Linux 2021-03-22 GETXATTR(2)