-The optional argument \fI-t\fP must be followed by \fBnfs\fP or
-\fBufs\fP to indicate the file system type. The type \fBufs\fP is
-the default.
-The \fI-o\fP argument followed by \fIoptions\fP, which is a comma
-separated string of any of the following list,
-can be used to override the defaults for an nfs mount.
-.PP
-.IP "hard" 12
-I/O system calls will retry until the server responds (default)
-.IP "soft" 12
-I/O system calls will fail and return errno after \fIretrans\fP request
-retransmissions
-.IP "bg" 12
-If the first mount request times out, do retries in background
-.IP "intr" 12
-I/O system calls can be interrupted.
-.IP "rsize=#" 12
-Set read size to \fI#\fP bytes.
-.IP "wsize=#" 12
-Set write size to \fI#\fP bytes.
-.IP "retry=#" 12
-Set mount retry count to \fI#\fP.
-.IP "retrans=#" 12
-Set retransmission count for nfs rpc's to \fI#\fP.
-.IP "timeo=#" 12
-Set initial nfs timeout to \fI#\fP in 0.1 sec intervals.
-.fi
-.PP
-.I Umount
-announces to the system that the removable file system \fInode\fP
-or whatever removable file system was previously mounted on device
-\fIspecial\fP should be removed.
-.PP
-If the \fI-a\fP option is present for either
-.I mount
+This option is useful in conjunction with the
+.Fl v
+flag to
+determine what the
+.Nm mount
+command is trying to do.
+.It Fl o
+Options are specified with a
+.Fl o
+flag
+followed by a comma separated string of options.
+The following options apply to any file system that is being mounted:
+.Bl -tag -width indent
+.It noexec
+Do not allow execution of any binaries on the mounted file system.
+This options is useful for a server that has file systems containing
+binaries for architectures other than its own.
+.It nosuid
+Do not allow set-user-identifier or set-group-identifier bits to take effect.
+.It nodev
+Do not interpret character or block special devices on the file system.
+This options is useful for a server that has file systems containing
+special devices for architectures other than its own.
+.It synchronous
+All
+.Tn I/O
+to the file system should be done synchronously.
+.El
+.It Fl r
+The file system object is to be mounted read-only.
+.It Fl t Ar "ufs \\*(Ba lfs \\*(Ba external type"
+The argument following the
+.Fl t
+is used to indicate the file system type.
+The type
+.Ar ufs
+is the default.
+The \fI-t\fP option can be used
+to indicate that the actions should only be taken on
+filesystems of the specified type.
+More than one type may be specified in a comma separated list.
+The list of filesystem types can be prefixed with ``no'' to
+specify the filesystem types on which no action should be taken.
+For example, the
+.Nm mount
+command:
+.Bd -literal -offset indent
+mount -a -t nonfs,mfs
+.Ed
+.Pp
+mounts all filesystems except those of type
+.Tn NFS
+and
+.Tn MFS .
+.Pp
+If the type is not one of the internally known types,
+mount will attempt to execute a program in
+.Pa /sbin/mount_ Ns Em XXX
+where
+.Em XXX
+is replaced by the type name.
+For example, nfs filesystems are mounted by the program
+.Pa /sbin/mount_nfs .
+.It Fl u
+The
+.Fl u
+flag indicates that the status of an already mounted file
+system should be changed.
+Any of the options discussed above (the
+.Fl o
+option)
+may be changed;
+also a file system can be changed from read-only to read-write.
+The set of options is determined by first extracting the options
+for the file system from the
+.Xr fstab
+table,
+then applying any options specified by the
+.Fl o
+argument,
+and finally applying the
+.Fl r
projects / unix-history / blobdiff