1GETXATTR(2)                Linux Programmer's Manual               GETXATTR(2)
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NAME

6       getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value
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SYNOPSIS

9       #include <sys/types.h>
10       #include <sys/xattr.h>
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12       ssize_t getxattr(const char *path, const char *name,
13                        void *value, size_t size);
14       ssize_t lgetxattr(const char *path, const char *name,
15                        void *value, size_t size);
16       ssize_t fgetxattr(int fd, const char *name,
17                        void *value, size_t size);
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DESCRIPTION

20       Extended attributes are name:value pairs associated with inodes (files,
21       directories, symbolic links, etc.).  They are extensions to the  normal
22       attributes  which  are  associated with all inodes in the system (i.e.,
23       the stat(2) data).  A complete overview of extended attributes concepts
24       can be found in xattr(7).
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26       getxattr()  retrieves the value of the extended attribute identified by
27       name and associated  with  the  given  path  in  the  filesystem.   The
28       attribute value is placed in the buffer pointed to by value; size spec‐
29       ifies the size of that buffer.  The return value of  the  call  is  the
30       number of bytes placed in value.
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32       lgetxattr()  is  identical  to getxattr(), except in the case of a sym‐
33       bolic link, where the link itself is interrogated, not the file that it
34       refers to.
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36       fgetxattr()  is identical to getxattr(), only the open file referred to
37       by fd (as returned by open(2)) is interrogated in place of path.
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39       An extended attribute name  is  a  null-terminated  string.   The  name
40       includes  a namespace prefix; there may be several, disjoint namespaces
41       associated  with  an  individual  inode.   The  value  of  an  extended
42       attribute  is  a  chunk  of  arbitrary  textual or binary data that was
43       assigned using setxattr(2).
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45       If size is specified as zero, these calls return the  current  size  of
46       the  named extended attribute (and leave value unchanged).  This can be
47       used to determine the size of the buffer that should be supplied  in  a
48       subsequent  call.   (But, bear in mind that there is a possibility that
49       the attribute value may change between the two calls,  so  that  it  is
50       still necessary to check the return status from the second call.)
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RETURN VALUE

53       On  success,  these  calls return a nonnegative value which is the size
54       (in bytes) of the extended attribute value.  On failure, -1 is returned
55       and errno is set appropriately.
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ERRORS

58       E2BIG  The  size of the attribute value is larger than the maximum size
59              allowed; the attribute cannot be retrieved.  This can happen  on
60              filesystems  that  support  very  large attribute values such as
61              NFSv4, for example.
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63       ENOATTR
64              The named attribute does not exist, or the process has no access
65              to this attribute.  (ENOATTR is defined to be a synonym for ENO‐
66              DATA in <attr/xattr.h>.)
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68       ENOTSUP
69              Extended attributes are not supported by the filesystem, or  are
70              disabled.
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72       ERANGE The size of the value buffer is too small to hold the result.
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74       In addition, the errors documented in stat(2) can also occur.
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VERSIONS

77       These system calls have been available on Linux since kernel 2.4; glibc
78       support is provided since version 2.3.
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CONFORMING TO

81       These system calls are Linux-specific.
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EXAMPLE

84       See listxattr(2).
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SEE ALSO

87       getfattr(1), setfattr(1), listxattr(2), open(2), removexattr(2),  setx‐
88       attr(2), stat(2), symlink(7), xattr(7)
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COLOPHON

91       This  page  is  part of release 4.16 of the Linux man-pages project.  A
92       description of the project, information about reporting bugs,  and  the
93       latest     version     of     this    page,    can    be    found    at
94       https://www.kernel.org/doc/man-pages/.
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98Linux                             2017-03-13                       GETXATTR(2)
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