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NFSCLNT(2)                  BSD System Calls Manual                 NFSCLNT(2)

NAME
     nfsclnt -- NFS client services

SYNOPSIS
     #include <unistd.h>
     #include <nfs/nfs.h>

     int
     nfsclnt(int flags, void *argstructp);

DESCRIPTION
     The nfsclnt() function is used by the NFS client daemons to pass informa-tion information
     tion into and out of the kernel.  The flags argument consists of several
     bits that show what action is to be taken once in the kernel and the
     argstructp points to any corresponding data that the action may require.

     rpc.lockd(8) calls nfsclnt() with the flag NFSCLNT_LOCKDANS and a pointer
     to a

     struct lockd_ans {
             int             la_version;             /* lockd_ans version */
             int             la_errno;               /* return status */
             u_int64_t       la_xid;                 /* unique message transaction ID */
             int             la_flags;               /* answer flags */
             pid_t           la_pid;                 /* pid of lock requester/owner */
             off_t           la_start;               /* lock starting offset */
             off_t           la_len;                 /* lock length */
             int             la_fh_len;              /* The file handle length. */
             u_int8_t        la_fh[NFSV3_MAX_FH_SIZE];/* The file handle. */
     };

     to pass the response to an NFS file locking request back into the kernel.

RETURN VALUES
     Upon successful completion, a value of 0 is returned.  Otherwise, -1 is
     returned and the global variable errno is set to specify the error.

ERRORS
     [EPERM]            The caller is not the super-user.

     [EINVAL]           The action specified by the flags argument was not
                        valid.

     [EFAULT]           argstructp points to an invalid address.

     [EPIPE]            The response doesn't match any currently-outstanding
                        lock request.

SEE ALSO
     rpc.lockd(8)

BUGS
     The nfsclnt system call is designed specifically for the NFS client dae-mons daemons
     mons and as such is specific to their requirements.  Several fields of
     the argument structures are assumed to be valid, such that nfsclnt must
     be used with extreme care.

BSD                             January 9, 2007                            BSD