4.3BSD-Reno/share/man/cat8/umount.0
MOUNT(8) 1990 MOUNT(8)
NNAAMMEE
mount, umount - mount and dismount file systems
SSYYNNOOPPSSIISS
mmoouunntt [ --aaffrrwwuu ] [ --tt nfs | ufs | external_type ]
mmoouunntt [ --ffrrwwuu ] special | node
mmoouunntt [ --ffrrwwuu ] [ --tt nfs | ufs | external_type ] [ --oo
options ] special node
uummoouunntt [ --aaff ] [ --tt nfs | ufs | external_type ]
uummoouunntt [ --ff ] special | node
DDEESSCCRRIIPPTTIIOONN
_M_o_u_n_t announces to the system that a removable file system
is present on the block device _s_p_e_c_i_a_l or the remote node
``rhost:path''. The file _n_o_d_e must exist already and it must
be a directory. It becomes the name of the newly mounted
root. The optional arguments -_r and -_w indicate that the
file system is to be mounted read-only or read-write,
respectively. If either _s_p_e_c_i_a_l or _f_i_l_e are not provided,
the appropriate information is taken from the _f_s_t_a_b file.
The -_f option causes everything to be done except for the
actual system call; if it's not obvious, this ``fakes''
mounting the file system. This option is useful in conjunc-
tion with the -_v flag to determine what the _m_o_u_n_t command is
trying to do.
The optional argument -_t can be used to indicate the file
system type. The type uuffss is the default. If the type is
not one of the internally known types, mount will attempt to
execute a program in //ssbbiinn//mmoouunntt__XXXXXX where XXXXXX is replaced
by the type name. The standard mount options (see below)
are parsed and passed to external program via the -_F option
as a decimal number. Any additional options specific to the
program can be passed as a comma separated list; these
options are distinguished by starting with a - (dash).
Those options that take a value are specified using the syn-
tax -option=value. For example, the mount command:
mount -t mfs -o nosuid,-N,-s=4000 /dev/dk0b /tmp
causes mount to attempt to execute:
/sbin/mount_mfs -F 8 -N -s 4000 /dev/dk0b /tmp
Options are specified by a -_o argument followed by a comma
separated string of options. The following options apply to
any file system that is being mounted:
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.
nosuid Do not allow set-user-identifier or set-group-
Printed 7/27/90 June 1
MOUNT(8) 1990 MOUNT(8)
identifier bits to take effect.
nodev Do not interpret character or block special dev-
ices on the file system. This options is useful
for a server that has file systems containing
special devices for architectures other than its
own.
synchronous All I/O to the file system should be done syn-
chronously.
The -_u flag indicates that the status of an already mounted
file system should be changed. Any of the options above 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 _f_s_t_a_b
table, then applying any options specified by the -_o argu-
ment, and finally applying the -_r or -_w option.
The following list can be used to override the defaults for
an nfs mount:
hard I/O system calls will retry until the server
responds (default)
soft I/O system calls will fail and return errno
after _r_e_t_r_a_n_s request retransmissions
spongy Soft semantics for the stat, lookup, fsstat,
readlink and readdir filesystem operations and
hard semantics for the others. This option is
meant to be similar to hard, except that
processes will not be hung forever when they
trip over mount points to dead servers.
bg If the first mount request times out, do retries
in background
intr I/O system calls can be interrupted.
noconn Do not connect the socket. Used for UDP servers
that send replies from a socket other than the
nfs server socket.
tcp Use TCP transport instead of UDP.
rsize=# Set read size to # bytes.
wsize=# Set write size to # bytes.
retry=# Set mount retry count to #.
Printed 7/27/90 June 2
MOUNT(8) 1990 MOUNT(8)
retrans=# Set retransmission count for nfs rpc's to #.
timeo=# Set initial nfs timeout to # in 0.1 sec inter-
vals.
_U_m_o_u_n_t announces to the system that the removable file sys-
tem _n_o_d_e or whatever removable file system was previously
mounted on device _s_p_e_c_i_a_l should be removed. If the -_f
option is specified for _u_m_o_u_n_t, the file system is forcibly
unmounted. Active special devices continue to work, but all
other files return errors if further accesses are attempted.
The root file system cannot be forcibly unmounted.
If the -_a option is present for either _m_o_u_n_t or _u_m_o_u_n_t, all
of the file systems described in _f_s_t_a_b are mounted or
unmounted. The optional argument -_t 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 mount
command:
mount -a -t nonfs,mfs
mounts all filesystems except those of type NFS and MFS.
The system maintains a list of currently mounted file sys-
tems. If invoked without an argument, _m_o_u_n_t prints the
list. The optional argument -_t can be used to indicate that
only filesystems of the specified type should be listed.
More than one type may be specified in a comma separated
list. The list of filesystem types can be prefixed with
``no'' to indicate the types of filesystems to be excluded
from the listing.
Physically write-protected and magnetic tape file systems
must be mounted read-only or errors will occur when access
times are updated, whether or not any explicit write is
attempted.
FFIILLEESS
/etc/fstab file system table
SSEEEE AALLSSOO
mount(2), unmount(2), fstab(5)
BBUUGGSS
Mounting garbaged file systems will crash the system.
Mounting a root directory on a non-directory makes some
apparently good path names invalid.
Printed 7/27/90 June 3