flock函数的锁文件的结构体

/usr/include/asm-generic/fcntl.h

root@SHPD18F-SP01:/home/sftp_root/tmp# cat /usr/include/asm-generic/fcntl.h 
#ifndef _ASM_GENERIC_FCNTL_H
#define _ASM_GENERIC_FCNTL_H

#include <linux/types.h>

/*
 * FMODE_EXEC is 0x20
 * FMODE_NONOTIFY is 0x1000000
 * These cannot be used by userspace O_* until internal and external open
 * flags are split.
 * -Eric Paris
 */

/*
 * When introducing new O_* bits, please check its uniqueness in fcntl_init().
 */

#define O_ACCMODE       00000003
#define O_RDONLY        00000000
#define O_WRONLY        00000001
#define O_RDWR          00000002
#ifndef O_CREAT
#define O_CREAT         00000100        /* not fcntl */
#endif
#ifndef O_EXCL
#define O_EXCL          00000200        /* not fcntl */
#endif
#ifndef O_NOCTTY
#define O_NOCTTY        00000400        /* not fcntl */
#endif
#ifndef O_TRUNC
#define O_TRUNC         00001000        /* not fcntl */
#endif
#ifndef O_APPEND
#define O_APPEND        00002000
#endif
#ifndef O_NONBLOCK
#define O_NONBLOCK      00004000
#endif
#ifndef O_DSYNC
#define O_DSYNC         00010000        /* used to be O_SYNC, see below */
#endif
#ifndef FASYNC
#define FASYNC          00020000        /* fcntl, for BSD compatibility */
#endif
#ifndef O_DIRECT
#define O_DIRECT        00040000        /* direct disk access hint */
#endif
#ifndef O_LARGEFILE
#define O_LARGEFILE     00100000
#endif
#ifndef O_DIRECTORY
#define O_DIRECTORY     00200000        /* must be a directory */
#endif
#ifndef O_NOFOLLOW
#define O_NOFOLLOW      00400000        /* don't follow links */
#endif
#ifndef O_NOATIME
#define O_NOATIME       01000000
#endif
#ifndef O_CLOEXEC
#define O_CLOEXEC       02000000        /* set close_on_exec */
#endif

/*
 * Before Linux 2.6.33 only O_DSYNC semantics were implemented, but using
 * the O_SYNC flag.  We continue to use the existing numerical value
 * for O_DSYNC semantics now, but using the correct symbolic name for it.
 * This new value is used to request true Posix O_SYNC semantics.  It is
 * defined in this strange way to make sure applications compiled against
 * new headers get at least O_DSYNC semantics on older kernels.
 *
 * This has the nice side-effect that we can simply test for O_DSYNC
 * wherever we do not care if O_DSYNC or O_SYNC is used.
 *
 * Note: __O_SYNC must never be used directly.
 */
#ifndef O_SYNC
#define __O_SYNC        04000000
#define O_SYNC          (__O_SYNC|O_DSYNC)
#endif

#ifndef O_PATH
#define O_PATH          010000000
#endif

#ifndef __O_TMPFILE
#define __O_TMPFILE     020000000
#endif

/* a horrid kludge trying to make sure that this will fail on old kernels */
#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
#define O_TMPFILE_MASK (__O_TMPFILE | O_DIRECTORY | O_CREAT)      

#ifndef O_NDELAY
#define O_NDELAY        O_NONBLOCK
#endif

#define F_DUPFD         0       /* dup */
#define F_GETFD         1       /* get close_on_exec */
#define F_SETFD         2       /* set/clear close_on_exec */
#define F_GETFL         3       /* get file->f_flags */
#define F_SETFL         4       /* set file->f_flags */
#ifndef F_GETLK
#define F_GETLK         5
#define F_SETLK         6
#define F_SETLKW        7
#endif
#ifndef F_SETOWN
#define F_SETOWN        8       /* for sockets. */
#define F_GETOWN        9       /* for sockets. */
#endif
#ifndef F_SETSIG
#define F_SETSIG        10      /* for sockets. */
#define F_GETSIG        11      /* for sockets. */
#endif

#ifndef CONFIG_64BIT
#ifndef F_GETLK64
#define F_GETLK64       12      /*  using 'struct flock64' */
#define F_SETLK64       13
#define F_SETLKW64      14
#endif
#endif

#ifndef F_SETOWN_EX
#define F_SETOWN_EX     15
#define F_GETOWN_EX     16
#endif

#ifndef F_GETOWNER_UIDS
#define F_GETOWNER_UIDS 17
#endif

#define F_OWNER_TID     0
#define F_OWNER_PID     1
#define F_OWNER_PGRP    2

struct f_owner_ex {
        int     type;
        __kernel_pid_t  pid;
};

/* for F_[GET|SET]FL */
#define FD_CLOEXEC      1       /* actually anything with low bit set goes */

/* for posix fcntl() and lockf() */
#ifndef F_RDLCK
#define F_RDLCK         0
#define F_WRLCK         1
#define F_UNLCK         2
#endif

/* for old implementation of bsd flock () */
#ifndef F_EXLCK
#define F_EXLCK         4       /* or 3 */
#define F_SHLCK         8       /* or 4 */
#endif

/* operations for bsd flock(), also used by the kernel implementation */
#define LOCK_SH         1       /* shared lock */
#define LOCK_EX         2       /* exclusive lock */
#define LOCK_NB         4       /* or'd with one of the above to prevent
                                   blocking */
#define LOCK_UN         8       /* remove lock */

#define LOCK_MAND       32      /* This is a mandatory flock ... */
#define LOCK_READ       64      /* which allows concurrent read operations */
#define LOCK_WRITE      128     /* which allows concurrent write operations */
#define LOCK_RW         192     /* which allows concurrent read & write ops */

#define F_LINUX_SPECIFIC_BASE   1024

#ifndef HAVE_ARCH_STRUCT_FLOCK
#ifndef __ARCH_FLOCK_PAD
#define __ARCH_FLOCK_PAD
#endif

struct flock {
        short   l_type;
        short   l_whence;
        __kernel_off_t  l_start;
        __kernel_off_t  l_len;
        __kernel_pid_t  l_pid;
        __ARCH_FLOCK_PAD
};
#endif

#ifndef CONFIG_64BIT

#ifndef HAVE_ARCH_STRUCT_FLOCK64
#ifndef __ARCH_FLOCK64_PAD
#define __ARCH_FLOCK64_PAD
#endif

struct flock64 {
        short  l_type;
        short  l_whence;
        __kernel_loff_t l_start;
        __kernel_loff_t l_len;
        __kernel_pid_t  l_pid;
        __ARCH_FLOCK64_PAD
};
#endif
#endif /* !CONFIG_64BIT */

#endif /* _ASM_GENERIC_FCNTL_H */