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       getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value


       #include <sys/types.h>
       #include <attr/xattr.h>

       ssize_t getxattr (const char *path, const char *name,
                            void *value, size_t size);
       ssize_t lgetxattr (const char *path, const char *name,
                            void *value, size_t size);
       ssize_t fgetxattr (int filedes, const char *name,
                            void *value, size_t size);


       Extended attributes are name:value pairs associated with inodes (files,
       directories,  symlinks,  etc).   They  are  extensions  to  the  normal
       attributes which are associated with all inodes in the system (i.e. the
       stat(2) data).  A complete overview of extended attributes concepts can
       be found in attr(5).

       getxattr  retrieves  the  value of the extended attribute identified by
       name and associated with the given path in the filesystem.  The  length
       of the attribute value is returned.

       lgetxattr  is  identical  to getxattr, except in the case of a symbolic
       link, where the link itself is  interrogated,  not  the  file  that  it
       refers to.

       fgetxattr  is  identical  to getxattr, only the open file pointed to by
       filedes (as returned by open(2)) is interrogated in place of path.

       An extended attribute name is a  simple  NULL-terminated  string.   The
       name  includes  a  namespace  prefix  -  there may be several, disjoint
       namespaces associated with  an  individual  inode.   The  value  of  an
       extended  attribute  is  a chunk of arbitrary textual or binary data of
       specified length.

       An empty buffer of size zero can be passed into these calls  to  return
       the  current size of the named extended attribute, which can be used to
       estimate the size of a buffer which is sufficiently large to  hold  the
       value associated with the extended attribute.

       The  interface  is  designed to allow guessing of initial buffer sizes,
       and to enlarge buffers when the return value indicates that the  buffer
       provided was too small.


       On  success,  a  positive number is returned indicating the size of the
       extended attribute value.  On failure, -1 is returned and errno is  set

       If  the named attribute does not exist, or the process has no access to
       this attribute, errno is set to ENOATTR.

       If the size of the value buffer is too small to hold the result,  errno
       is set to ERANGE.

       If  extended  attributes  are  not  supported by the filesystem, or are
       disabled, errno is set to ENOTSUP.

       The errors documented for the stat(2) system call are  also  applicable


       Andreas   Gruenbacher,  <>  and  the  SGI  XFS
       development team, <>.  Please send any bug reports
       or comments to these addresses.


       getfattr(1),  setfattr(1), open(2), stat(2), setxattr(2), listxattr(2),
       removexattr(2), and attr(5).