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.Dd January 9, 2007
.Dt FHOPEN 2
.Os
.Sh NAME
.Nm fhopen
.Nd open a file by file handle
.Sh SYNOPSIS
.Fd #include <sys/types.h>
.Fd #include <sys/mount.h>
.Ft int
.Fn fhopen "const struct fhandle *fhp" "int flags"
.Sh DESCRIPTION
The file specified by the given file handle is opened for reading and/or
writing, as specified by the argument
.Fa flags ;
the file descriptor is returned to the calling process.
.Pp
This system call is restricted to the super-user and is used by an
NFS server's
.Xr rpc.lockd 8
daemon to open a file in order to perform locking operations on it.
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, -1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn fhopen
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq ESTALE
The file handle no longer refers to a valid, NFS-exported object.
.It Bq EPERM
The caller is not the super-user.
.It Bq EINVAL
There was a problem with the value of one of the arguments.
.It Bq EFAULT
.Fa fhp
points to an invalid address.
.El
.Sh SEE ALSO
.Xr rpc.lockd 8