add SEEK_DATA/SEEK_HOLE

include/stdio.h

@@ -110,7 +110,10 @@ typedef __STDIO_fpos64_t fpos64_t;
 #define SEEK_SET	0	/* Seek from beginning of file.  */
 #define SEEK_CUR	1	/* Seek from current position.  */
 #define SEEK_END	2	/* Seek from end of file.  */
-
+#ifdef __USE_GNU
+# define SEEK_DATA      3       /* Seek to next data.  */
+# define SEEK_HOLE      4       /* Seek to next hole.  */
+#endif
 
 #if defined __USE_SVID || defined __USE_XOPEN
 /* Default path prefix for `mkstemp'.  */

include/unistd.h

@@ -316,6 +316,10 @@ libc_hidden_proto(faccessat)
 # define SEEK_SET	0	/* Seek from beginning of file.  */
 # define SEEK_CUR	1	/* Seek from current position.  */
 # define SEEK_END	2	/* Seek from end of file.  */
+# ifdef __USE_GNU
+#  define SEEK_DATA     3       /* Seek to next data.  */
+#  define SEEK_HOLE     4       /* Seek to next hole.  */
+# endif
 #endif
 
 #if defined __USE_BSD && !defined L_SET