1. 根目录:
2. include
3. linux
4. fcntl.h

#ifndef _LINUX_FCNTL_H
#define _LINUX_FCNTL_H

#include <uapi/linux/fcntl.h>


#ifndef force_o_largefile
#define force_o_largefile() (BITS_PER_LONG != 32)
#endif

#if BITS_PER_LONG == 32
#define IS_GETLK32(cmd)		((cmd) == F_GETLK)
#define IS_SETLK32(cmd)		((cmd) == F_SETLK)
#define IS_SETLKW32(cmd)	((cmd) == F_SETLKW)
#define IS_GETLK64(cmd)		((cmd) == F_GETLK64)
#define IS_SETLK64(cmd)		((cmd) == F_SETLK64)
#define IS_SETLKW64(cmd)	((cmd) == F_SETLKW64)
#else
#define IS_GETLK32(cmd)		(0)
#define IS_SETLK32(cmd)		(0)
#define IS_SETLKW32(cmd)	(0)
#define IS_GETLK64(cmd)		((cmd) == F_GETLK)
#define IS_SETLK64(cmd)		((cmd) == F_SETLK)
#define IS_SETLKW64(cmd)	((cmd) == F_SETLKW)
#endif /* BITS_PER_LONG == 32 */

#define IS_GETLK(cmd)	(IS_GETLK32(cmd)  || IS_GETLK64(cmd))
#define IS_SETLK(cmd)	(IS_SETLK32(cmd)  || IS_SETLK64(cmd))
#define IS_SETLKW(cmd)	(IS_SETLKW32(cmd) || IS_SETLKW64(cmd))

#endif