[apple/libc.git] / gen / FreeBSD / getmntinfo.3

.\" Copyright (c) 1989, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)getmntinfo.3	8.1 (Berkeley) 6/9/93
.\" $FreeBSD: src/lib/libc/gen/getmntinfo.3,v 1.13 2007/01/09 00:27:54 imp Exp $
.\"
.Dd May 4, 2010
.Dt GETMNTINFO 3
.Os
.Sh NAME
.Nm getmntinfo
.Nm getmntinfo64
.Nd get information about mounted file systems
.Sh SYNOPSIS
.In sys/param.h
.In sys/ucred.h
.In sys/mount.h
.Ft int
.Fn getmntinfo "struct statfs **mntbufp" "int flags"
.Sh TRANSITIIONAL SYNOPSIS (NOW DEPRECATED)
.Ft int
.br
.Fn getmntinfo64 "struct statfs64 **mntbufp" "int flags" ;
.Sh DESCRIPTION
The
.Fn getmntinfo
function
returns an array of
.Ft statfs
structures describing each currently mounted file system (see
.Xr statfs 2 ) .
As
.Xr statfs 2
indicates, the structure is defined differently depending on
whether the macro _DARWIN_FEATURE_64_BIT_INODE is defined (see
.Xr stat 2
for more information on this macro).
.Pp
The
.Fn getmntinfo
function
passes its
.Fa flags
argument transparently to
.Xr getfsstat 2 .
.Sh RETURN VALUES
On successful completion,
.Fn getmntinfo
returns a count of the number of elements in the array.
The pointer to the array is stored into
.Fa mntbufp .
.Pp
If an error occurs, zero is returned and the external variable
.Va errno
is set to indicate the error.
Although the pointer
.Fa mntbufp
will be unmodified, any information previously returned by
.Fn getmntinfo
will be lost.
.Sh ERRORS
The
.Fn getmntinfo
function
may fail and set errno for any of the errors specified for the library
routines
.Xr getfsstat 2
or
.Xr malloc 3 .
.Sh TRANSITIONAL DESCRIPTION (NOW DEPRECATED)
The
.Fn getmntinfo64
routine is equivalent to its corresponding non-64-suffixed routine,
when 64-bit inodes are in effect.
It was added before there was support for the symbol variants, and so is
now deprecated.
Instead of using it, set the
.Dv _DARWIN_USE_64_BIT_INODE
macro before including header files to force 64-bit inode support.
.Pp
The
.Ft statfs64
structure used by this deprecated routine is the same as the
.Ft statfs
structure when 64-bit inodes are in effect.
.Sh SEE ALSO
.Xr getfsstat 2 ,
.Xr mount 2 ,
.Xr stat 2 ,
.Xr statfs 2 ,
.Xr mount 8
.Sh HISTORY
The
.Fn getmntinfo
function first appeared in
.Bx 4.4 .
.Sh BUGS
The
.Fn getmntinfo
function writes the array of structures to an internal static object
and returns
a pointer to that object.
Subsequent calls to
.Fn getmntinfo
will modify the same object.
.Pp
The memory allocated by
.Fn getmntinfo
cannot be
.Xr free 3 Ns 'd
by the application.
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1989, 1991, 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
e9ce8d39 A	12	.\" 4. Neither the name of the University nor the names of its contributors
	13	.\" may be used to endorse or promote products derived from this software
	14	.\" without specific prior written permission.
	15	.\"
	16	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	17	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	18	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	19	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	20	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	21	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	22	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	23	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	24	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	25	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	26	.\" SUCH DAMAGE.
	27	.\"
5b2abdfb	28	.\" @(#)getmntinfo.3 8.1 (Berkeley) 6/9/93
1f2f436a	29	.\" $FreeBSD: src/lib/libc/gen/getmntinfo.3,v 1.13 2007/01/09 00:27:54 imp Exp $
e9ce8d39	30	.\"
ad3c9f2a	31	.Dd May 4, 2010
5b2abdfb	32	.Dt GETMNTINFO 3
e9ce8d39 A	33	.Os
e9ce8d39 A	34	.Sh NAME
5b2abdfb	35	.Nm getmntinfo
ad3c9f2a	36	.Nm getmntinfo64
5b2abdfb	37	.Nd get information about mounted file systems
e9ce8d39	38	.Sh SYNOPSIS
5b2abdfb A	39	.In sys/param.h
	40	.In sys/ucred.h
	41	.In sys/mount.h
e9ce8d39	42	.Ft int
5b2abdfb	43	.Fn getmntinfo "struct statfs **mntbufp" "int flags"
ad3c9f2a A	44	.Sh TRANSITIIONAL SYNOPSIS (NOW DEPRECATED)
	45	.Ft int
	46	.br
	47	.Fn getmntinfo64 "struct statfs64 **mntbufp" "int flags" ;
e9ce8d39 A	48	.Sh DESCRIPTION
e9ce8d39 A	49	The
5b2abdfb A	50	.Fn getmntinfo
	51	function
	52	returns an array of
ad3c9f2a	53	.Ft statfs
5b2abdfb A	54	structures describing each currently mounted file system (see
5b2abdfb A	55	.Xr statfs 2 ) .
ad3c9f2a A	56	As
	57	.Xr statfs 2
	58	indicates, the structure is defined differently depending on
	59	whether the macro _DARWIN_FEATURE_64_BIT_INODE is defined (see
	60	.Xr stat 2
	61	for more information on this macro).
5b2abdfb	62	.Pp
e9ce8d39	63	The
5b2abdfb A	64	.Fn getmntinfo
	65	function
	66	passes its
e9ce8d39	67	.Fa flags
9385eb3d	68	argument transparently to
5b2abdfb	69	.Xr getfsstat 2 .
e9ce8d39	70	.Sh RETURN VALUES
5b2abdfb A	71	On successful completion,
	72	.Fn getmntinfo
	73	returns a count of the number of elements in the array.
	74	The pointer to the array is stored into
	75	.Fa mntbufp .
	76	.Pp
	77	If an error occurs, zero is returned and the external variable
	78	.Va errno
	79	is set to indicate the error.
	80	Although the pointer
	81	.Fa mntbufp
	82	will be unmodified, any information previously returned by
	83	.Fn getmntinfo
	84	will be lost.
e9ce8d39	85	.Sh ERRORS
5b2abdfb A	86	The
	87	.Fn getmntinfo
	88	function
	89	may fail and set errno for any of the errors specified for the library
	90	routines
	91	.Xr getfsstat 2
	92	or
	93	.Xr malloc 3 .
ad3c9f2a A	94	.Sh TRANSITIONAL DESCRIPTION (NOW DEPRECATED)
	95	The
	96	.Fn getmntinfo64
	97	routine is equivalent to its corresponding non-64-suffixed routine,
	98	when 64-bit inodes are in effect.
	99	It was added before there was support for the symbol variants, and so is
	100	now deprecated.
	101	Instead of using it, set the
	102	.Dv _DARWIN_USE_64_BIT_INODE
	103	macro before including header files to force 64-bit inode support.
	104	.Pp
	105	The
	106	.Ft statfs64
	107	structure used by this deprecated routine is the same as the
	108	.Ft statfs
	109	structure when 64-bit inodes are in effect.
e9ce8d39	110	.Sh SEE ALSO
5b2abdfb A	111	.Xr getfsstat 2 ,
5b2abdfb A	112	.Xr mount 2 ,
ad3c9f2a	113	.Xr stat 2 ,
5b2abdfb A	114	.Xr statfs 2 ,
5b2abdfb A	115	.Xr mount 8
e9ce8d39 A	116	.Sh HISTORY
e9ce8d39 A	117	The
5b2abdfb	118	.Fn getmntinfo
e9ce8d39 A	119	function first appeared in
e9ce8d39 A	120	.Bx 4.4 .
5b2abdfb A	121	.Sh BUGS
	122	The
	123	.Fn getmntinfo
	124	function writes the array of structures to an internal static object
	125	and returns
	126	a pointer to that object.
	127	Subsequent calls to
	128	.Fn getmntinfo
	129	will modify the same object.
	130	.Pp
	131	The memory allocated by
	132	.Fn getmntinfo
	133	cannot be
	134	.Xr free 3 Ns 'd
	135	by the application.