• NAME
  
  getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value
• SYNOPSIS
  

  
   #include <sys/types.h>
   #include <attr/xattr.h>
  
   ssize_t getxattr (const char\ * path , const char\ * name ,
    \t\t\t\t void\ * value , size_t  size );   ssize_t lgetxattr (const char\ * path , const char\ * name ,   \t\t\t\t void\ * value , size_t  size );   ssize_t fgetxattr (int  filedes , const char\ * name ,   \t\t\t\t void\ * value , size_t  size ); 

• DESCRIPTION
  
  Extended attributes are
  name :c
  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.
  
• RETURN VALUE
  
  On success, a positive number is returned indicating the size of the
  extended attribute value.
  On failure, -1 is returned and
  errno
  is set appropriately.
  
  
  
  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 here.
  
• AUTHORS
  
  Andreas Gruenbacher,
  < a.gruenbacher@bestbits.at > and the SGI XFS development team,
  < linux-xfs@oss.sgi.com >. Please send any bug reports or comments to these addresses.
  
• SEE ALSO
  
  getfattr(1) ,
  setfattr(1) ,
  open(2) ,
  stat(2) ,
  setxattr(2) ,
  listxattr(2) ,
  removexattr(2) ,
  and
  attr(5) .
  

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