[unix-history] / usr / src / lib / libc / sys / mount.2

.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)mount.2	6.1 (Berkeley) %G%
.\"
.TH MOUNT 2 ""
.UC 4
.SH NAME
mount, umount \- mount or remove file system
.SH SYNOPSIS
.nf
.ft B
mount(special, name, rwflag)
char *special, *name;
int rwflag;
.PP
.ft B
umount(special)
char *special;
.fi
.SH DESCRIPTION
.I Mount
announces to the system that a removable file system has
been mounted on
the block-structured special file
.I special;
from now on, references to file
.I name
will refer to
the root file on the newly mounted file system.
.I Special
and
.I name
are pointers to null-terminated strings
containing the appropriate path names.
.PP
.I Name
must exist already. 
.I Name
must be a directory.
Its old contents
are inaccessible while the file system
is mounted.
.PP
The
.I rwflag
argument determines whether
the file system can be written on; if it is 0 writing
is allowed, if non-zero no writing is done.
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.
.PP
.I Umount
announces to the system that the
.I special
file is no longer to contain a removable file system.
The associated file reverts to its ordinary interpretation.
.SH "RETURN VALUE
.I Mount
returns 0 if the action occurred, \-1 if
.I special
is inaccessible or not an appropriate file, if
.I name
does not exist, if
.I special
is already mounted, if
.I name
is in use, or if
there are already too many
file systems mounted.
.PP
.I Umount
returns 0 if the action occurred; \-1 if
if the special file is inaccessible or
does not have a mounted file system,
or if there are active files in the mounted 
file system.
.SH ERRORS
.I Mount
will fail when one of the following occurs:
.TP 15
[NODEV]
The caller is not the super-user.
.TP 15
[NODEV]
.I Special
does not exist.
.TP 15
[ENOTBLK]
.I Special
is not a block device.
.TP 15
[ENXIO]
The major device number of 
.I special
is out of range (this indicates no device driver exists
for the associated hardware).
.TP 15
[EPERM]
The pathname contains a character with the high-order bit set.
.TP 15
[ENOTDIR]
A component of the path prefix in
.I name
is not a directory.
.TP 15
[EROFS]
.I Name
resides on a read-only file system.
.TP 15
[EBUSY]
.I Name
is not a directory, or another process currently
holds a reference to it.
.TP 15
[EBUSY]
No space remains in the mount table.
.TP 15
[EBUSY]
The super block for the file system had a bad magic
number or an out of range block size.
.TP 15
[EBUSY]
Not enough memory was available to read the cylinder
group information for the file system.
.TP 15
[EBUSY]
An i/o error occurred while reading the super block or
cylinder group information.
.PP
.I Umount
may fail with one of the following errors:
.TP 15
[NODEV]
The caller is not the super-user.
.TP 15
[NODEV]
.I Special
does not exist.
.TP 15
[ENOTBLK]
.I Special
is not a block device.
.TP 15
[ENXIO]
The major device number of 
.I special
is out of range (this indicates no device driver exists
for the associated hardware).
.TP 15
[EINVAL]
The requested device is not in the mount table.
.TP 15
[EBUSY]
A process is holding a reference to a file located
on the file system.
.SH "SEE ALSO"
mount(8), umount(8)
.SH BUGS
The error codes are in a state of disarray; too many errors
appear to the caller as one value.
Commit	Line	Data
75f4d1ff KM	1	.\" Copyright (c) 1980 Regents of the University of California.
	2	.\" All rights reserved. The Berkeley software License Agreement
	3	.\" specifies the terms and conditions for redistribution.
	4	.\"
acbf19e9	5	.\" @(#)mount.2 6.1 (Berkeley) %G%
75f4d1ff	6	.\"
acbf19e9	7	.TH MOUNT 2 ""
75f4d1ff KM	8	.UC 4
	9	.SH NAME
	10	mount, umount \- mount or remove file system
	11	.SH SYNOPSIS
	12	.nf
28e2febc KM	13	.ft B
	14	mount(special, name, rwflag)
	15	char special, name;
	16	int rwflag;
75f4d1ff	17	.PP
28e2febc KM	18	.ft B
	19	umount(special)
	20	char *special;
75f4d1ff KM	21	.fi
	22	.SH DESCRIPTION
	23	.I Mount
	24	announces to the system that a removable file system has
	25	been mounted on
	26	the block-structured special file
	27	.I special;
	28	from now on, references to file
	29	.I name
	30	will refer to
	31	the root file on the newly mounted file system.
	32	.I Special
	33	and
	34	.I name
	35	are pointers to null-terminated strings
	36	containing the appropriate path names.
	37	.PP
	38	.I Name
	39	must exist already.
	40	.I Name
28e2febc	41	must be a directory.
75f4d1ff KM	42	Its old contents
	43	are inaccessible while the file system
	44	is mounted.
	45	.PP
	46	The
	47	.I rwflag
	48	argument determines whether
	49	the file system can be written on; if it is 0 writing
	50	is allowed, if non-zero no writing is done.
	51	Physically write-protected and magnetic
	52	tape file systems must be mounted read-only or
	53	errors will occur when access times are updated,
	54	whether or not any
	55	explicit write is attempted.
	56	.PP
	57	.I Umount
	58	announces to the system that the
	59	.I special
	60	file is no longer to contain a removable file system.
	61	The associated file reverts to its ordinary interpretation.
28e2febc	62	.SH "RETURN VALUE
75f4d1ff	63	.I Mount
28e2febc	64	returns 0 if the action occurred, \-1 if
75f4d1ff	65	.I special
28e2febc	66	is inaccessible or not an appropriate file, if
75f4d1ff	67	.I name
28e2febc	68	does not exist, if
75f4d1ff	69	.I special
28e2febc	70	is already mounted, if
75f4d1ff	71	.I name
28e2febc	72	is in use, or if
75f4d1ff KM	73	there are already too many
	74	file systems mounted.
	75	.PP
	76	.I Umount
	77	returns 0 if the action occurred; \-1 if
	78	if the special file is inaccessible or
	79	does not have a mounted file system,
	80	or if there are active files in the mounted
	81	file system.
28e2febc KM	82	.SH ERRORS
	83	.I Mount
	84	will fail when one of the following occurs:
	85	.TP 15
	86	[NODEV]
	87	The caller is not the super-user.
	88	.TP 15
	89	[NODEV]
	90	.I Special
	91	does not exist.
	92	.TP 15
	93	[ENOTBLK]
	94	.I Special
	95	is not a block device.
	96	.TP 15
	97	[ENXIO]
	98	The major device number of
	99	.I special
	100	is out of range (this indicates no device driver exists
	101	for the associated hardware).
	102	.TP 15
	103	[EPERM]
	104	The pathname contains a character with the high-order bit set.
	105	.TP 15
	106	[ENOTDIR]
	107	A component of the path prefix in
	108	.I name
	109	is not a directory.
	110	.TP 15
	111	[EROFS]
	112	.I Name
	113	resides on a read-only file system.
	114	.TP 15
	115	[EBUSY]
	116	.I Name
	117	is not a directory, or another process currently
	118	holds a reference to it.
	119	.TP 15
	120	[EBUSY]
	121	No space remains in the mount table.
	122	.TP 15
	123	[EBUSY]
	124	The super block for the file system had a bad magic
	125	number or an out of range block size.
	126	.TP 15
	127	[EBUSY]
	128	Not enough memory was available to read the cylinder
	129	group information for the file system.
	130	.TP 15
	131	[EBUSY]
	132	An i/o error occurred while reading the super block or
	133	cylinder group information.
75f4d1ff	134	.PP
28e2febc KM	135	.I Umount
	136	may fail with one of the following errors:
	137	.TP 15
	138	[NODEV]
	139	The caller is not the super-user.
	140	.TP 15
	141	[NODEV]
	142	.I Special
	143	does not exist.
	144	.TP 15
	145	[ENOTBLK]
	146	.I Special
	147	is not a block device.
	148	.TP 15
	149	[ENXIO]
	150	The major device number of
	151	.I special
	152	is out of range (this indicates no device driver exists
	153	for the associated hardware).
	154	.TP 15
	155	[EINVAL]
	156	The requested device is not in the mount table.
	157	.TP 15
	158	[EBUSY]
	159	A process is holding a reference to a file located
	160	on the file system.
	161	.SH "SEE ALSO"
	162	mount(8), umount(8)
	163	.SH BUGS
	164	The error codes are in a state of disarray; too many errors
	165	appear to the caller as one value.