exportfs.2nfs

<B>Digital的Unix操作系统VAX 4.2源码</B>

.TH exportfs 2nfs
.SH Name
exportfs \- exports an NFS file system
.SH Syntax
.nf
.br
.br
.ft B
#include <sys/mount.h>
exportfs(name, rootuid, exflags)
char *name;
int rootuid, exflags;
.PP
.fi
.SH Description
.NXR "exportfs system call"
.NXR "file system" "exporting"
The 
.PN exportfs
system call allows the specified local file system to be mounted
remotely by an NFS client.  This system call is usually called from 
.PN mountd .
Security on the
exported file systems can be improved
by setting the root mapped user
ID,
.I rootuid,
and two mount structure flags,
.I exflags
for the local file system,
.I name.
.PP
The
.I name 
argument is a pointer to a null-terminated string containing
the path name of the file system being exported.
.PP
The
.I rootuid
argument is used to set the user ID that root maps to.  By default, root
maps to user id \-2.
.PP
The 
.I exflags 
argument contains the flags that are to be set in the mount structure
corresponding to
.I name.
The following flags are the only possible flags accepted by 
.PN exportfs:
.EX
#define M_NOFH          0x1000          /* no fhandle flag */
#define M_EXRONLY       0x2000          /* export read-only */
.EE
.PP
Setting the M_NOFH flag does not allow access to the fhandle of
the file system's root gnode.  The M_EXRONLY flag exports a filesystem
read only. 
.PP
The
.PN exportfs
system call returns a value of 0 upon successful completion of a 
operation, and \-1 upon failure.  
.SH Diagnostics
.TP 15
[EPERM]
Not superuser.
.TP 15
[EIO]
Not enough memory in the system to service the request.
.TP 15
[EFAULT]
Bad address or bad length of 
.I name.
.TP 15
[ENOENT]
The
.I name
cannot be found.
.SH See Also
exports(5nfs), mountd(8nfs)