Add AT_HANDLE_FID from Linux 6.5 to bits/fcntl-linux.h

[Joseph Myers]

Linux 6.5 adds a constant AT_HANDLE_FID; add it to glibc.  Because
this is a flag for the function name_to_handle_at declared in
bits/fcntl-linux.h, put the flag there rather than alongside other
AT_* flags in (OS-independent) fcntl.h.

Tested for x86_64.

diff --git a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
index df378c7b89..dd9d9baf09 100644
--- a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
+++ b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
@@ -368,6 +368,17 @@ struct file_handle
 # define MAX_HANDLE_SZ	128
 #endif
 
+#ifdef __USE_GNU
+/* Flags for name_to_handle_at.  See comment in fcntl.h about the use
+   of the same AT_* flag bits for different purposes in different
+   functions.  */
+# define AT_HANDLE_FID		AT_REMOVEDIR /* File handle is needed
+						to compare object
+						identity and may not
+						be usable to
+						open_by_handle_at.  */
+#endif
+
 __BEGIN_DECLS
 
 #ifdef __USE_GNU

-- 
Joseph S. Myers
joseph@codesourcery.com