getxattr(2)                                             System Calls Manual                                             getxattr(2)

       getxattr, lgetxattr, fgetxattr - retrieve an extended attribute value

       Standard C library (libc, -lc)

       #include <sys/xattr.h>

       ssize_t getxattr(const char *path, const char *name,
                        void value[.size], size_t size);
       ssize_t lgetxattr(const char *path, const char *name,
                        void value[.size], size_t size);
       ssize_t fgetxattr(int fd, const char *name,
                        void value[.size], size_t size);

       Extended attributes are name:value pairs associated with inodes (files, directories, symbolic links, etc.).  They are exten‐
       sions 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 xattr(7).

       getxattr()  retrieves  the  value  of  the  extended  attribute identified by name and associated with the given path in the
       filesystem.  The attribute value is placed in the buffer pointed to by value; size specifies the size of that  buffer.   The
       return value of the call is the number of bytes placed in value.

       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 referred to by fd (as returned by  open(2))  is  interrogated  in
       place of path.

       An  extended  attribute  name is a null-terminated string.  The name includes a namespace prefix; there may be several, dis‐
       joint namespaces associated with an individual inode.  The value of an extended attribute is a chunk of arbitrary textual or
       binary data that was assigned using setxattr(2).

       If  size  is  specified  as  zero,  these calls return the current size of the named extended attribute (and leave value un‐
       changed).  This can be used to determine the size of the buffer that should be supplied in a subsequent call.  (But, bear in
       mind that there is a possibility that the attribute value may change between the two calls, so that it is still necessary to
       check the return status from the second call.)

       On success, these calls return a nonnegative value which is the size (in bytes) of the extended attribute value.   On  fail‐
       ure, -1 is returned and errno is set to indicate the error.

       E2BIG  The size of the attribute value is larger than the maximum size allowed; the attribute cannot be retrieved.  This can
              happen on filesystems that support very large attribute values such as NFSv4, for example.

              The named attribute does not exist, or the process has no access to this attribute.

              Extended attributes are not supported by the filesystem, or are disabled.

       ERANGE The size of the value buffer is too small to hold the result.

       In addition, the errors documented in stat(2) can also occur.

       These system calls have been available since Linux 2.4; glibc support is provided since glibc 2.3.

       These system calls are Linux-specific.

       See listxattr(2).

       getfattr(1), setfattr(1), listxattr(2), open(2), removexattr(2), setxattr(2), stat(2), symlink(7), xattr(7)

Linux man-pages 6.03                                         2022-12-04                                                 getxattr(2)