[apple/xnu.git] / bsd / man / man2 / statfs.2

.\"	$NetBSD: statfs.2,v 1.10 1995/06/29 11:40:48 cgd Exp $
.\"
.\" 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.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 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.
.\"
.\"	@(#)statfs.2	8.3 (Berkeley) 2/11/94
.\"
.Dd February 11, 1994
.Dt STATFS 2
.Os
.Sh NAME
.Nm statfs
.Nd get file system statistics
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <sys/mount.h>
.Ft int
.Fn statfs "const char *path" "struct statfs *buf"
.Ft int
.Fn fstatfs "int fd" "struct statfs *buf"
.Sh DESCRIPTION
.Fn Statfs
returns information about a mounted file system.
.Fa Path
is the path name of any file within the mounted file system.
.Fa Buf
is a pointer to a statfs structure defined as follows:
.Bd -literal
typedef struct { int32_t val[2]; } fsid_t;

#define MFSNAMELEN   16 /* length of fs type name, including nul */
#define MNAMELEN     32	/* length of buffer for returned name */

struct statfs {
    short   f_type;	/* type of file system (unused; zero) */
    short   f_flags;	/* copy of mount flags */
    long    f_bsize;	/* fundamental file system block size */
    long    f_iosize;	/* optimal transfer block size */
    long    f_blocks;	/* total data blocks in file system */
    long    f_bfree;	/* free blocks in fs */
    long    f_bavail;	/* free blocks avail to non-superuser */
    long    f_files;	/* total file nodes in file system */
    long    f_ffree;	/* free file nodes in fs */
    fsid_t  f_fsid;	/* file system id (super-user only) */
    uid_t   f_owner;	/* user that mounted the file system */
    long    f_spare[4];	/* spare for later */
    char    f_fstypename[MFSNAMELEN]; /* fs type name */
    char    f_mntonname[MNAMELEN];    /* directory on which mounted */
    char    f_mntfromname[MNAMELEN];  /* mounted file system */
};
.Ed
.Pp
Fields that are undefined for a particular file system are set to -1.
.Fn Fstatfs
returns the same information about an open file referenced by descriptor
.Fa fd .
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, -1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn Statfs
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq Er ENOTDIR
A component of the path prefix of
.Fa Path
is not a directory.
.It Bq Er ENAMETOOLONG
The length of a component of
.Fa path
exceeds 
.Dv {NAME_MAX}
characters, or the length of
.Fa path
exceeds 
.Dv {PATH_MAX}
characters.
.It Bq Er ENOENT
The file referred to by
.Fa path
does not exist.
.It Bq Er EACCES
Search permission is denied for a component of the path prefix of
.Fa path .
.It Bq Er ELOOP
Too many symbolic links were encountered in translating
.Fa path .
.It Bq Er EFAULT
.Fa Buf
or
.Fa path
points to an invalid address.
.It Bq Er EIO
An
.Tn I/O
error occurred while reading from or writing to the file system.
.El
.Pp
.Fn Fstatfs
fails if one or more of the following are true:
.Bl -tag -width Er
.It Bq Er EBADF
.Fa fd
is not a valid open file descriptor.
.It Bq Er EFAULT
.Fa Buf
points to an invalid address.
.It Bq Er EIO
An
.Tn I/O
error occurred while reading from or writing to the file system.
.El
.Sh HISTORY
The
.Fn statfs
function first appeared in 4.4BSD.
Commit	Line	Data
9bccf70c A	1	.\" $NetBSD: statfs.2,v 1.10 1995/06/29 11:40:48 cgd Exp $
	2	.\"
	3	.\" Copyright (c) 1989, 1991, 1993
	4	.\" The Regents of the University of California. All rights reserved.
	5	.\"
	6	.\" Redistribution and use in source and binary forms, with or without
	7	.\" modification, are permitted provided that the following conditions
	8	.\" are met:
	9	.\" 1. Redistributions of source code must retain the above copyright
	10	.\" notice, this list of conditions and the following disclaimer.
	11	.\" 2. Redistributions in binary form must reproduce the above copyright
	12	.\" notice, this list of conditions and the following disclaimer in the
	13	.\" documentation and/or other materials provided with the distribution.
	14	.\" 3. All advertising materials mentioning features or use of this software
	15	.\" must display the following acknowledgement:
	16	.\" This product includes software developed by the University of
	17	.\" California, Berkeley and its contributors.
	18	.\" 4. Neither the name of the University nor the names of its contributors
	19	.\" may be used to endorse or promote products derived from this software
	20	.\" without specific prior written permission.
	21	.\"
	22	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	23	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	24	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	25	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	26	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	27	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	28	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	29	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	30	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	31	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	32	.\" SUCH DAMAGE.
	33	.\"
	34	.\" @(#)statfs.2 8.3 (Berkeley) 2/11/94
	35	.\"
	36	.Dd February 11, 1994
	37	.Dt STATFS 2
	38	.Os
	39	.Sh NAME
	40	.Nm statfs
	41	.Nd get file system statistics
	42	.Sh SYNOPSIS
	43	.Fd #include <sys/param.h>
	44	.Fd #include <sys/mount.h>
	45	.Ft int
	46	.Fn statfs "const char path" "struct statfs buf"
	47	.Ft int
	48	.Fn fstatfs "int fd" "struct statfs *buf"
	49	.Sh DESCRIPTION
	50	.Fn Statfs
	51	returns information about a mounted file system.
	52	.Fa Path
	53	is the path name of any file within the mounted file system.
	54	.Fa Buf
	55	is a pointer to a statfs structure defined as follows:
	56	.Bd -literal
	57	typedef struct { int32_t val[2]; } fsid_t;
	58
	59	#define MFSNAMELEN 16 /* length of fs type name, including nul */
	60	#define MNAMELEN 32 /* length of buffer for returned name */
	61
	62	struct statfs {
	63	short f_type; /* type of file system (unused; zero) */
	64	short f_flags; /* copy of mount flags */
65	long f_bsize; /* fundamental file system block size */
66	long f_iosize; /* optimal transfer block size */
67	long f_blocks; /* total data blocks in file system */
68	long f_bfree; /* free blocks in fs */
69	long f_bavail; /* free blocks avail to non-superuser */
70	long f_files; /* total file nodes in file system */
71	long f_ffree; /* free file nodes in fs */
72	fsid_t f_fsid; /* file system id (super-user only) */
73	uid_t f_owner; /* user that mounted the file system */
74	long f_spare[4]; /* spare for later */
75	char f_fstypename[MFSNAMELEN]; /* fs type name */
76	char f_mntonname[MNAMELEN]; /* directory on which mounted */
77	char f_mntfromname[MNAMELEN]; /* mounted file system */
78	};
79	.Ed
80	.Pp
81	Fields that are undefined for a particular file system are set to -1.
82	.Fn Fstatfs
83	returns the same information about an open file referenced by descriptor
84	.Fa fd .
85	.Sh RETURN VALUES
86	Upon successful completion, a value of 0 is returned.
87	Otherwise, -1 is returned and the global variable
88	.Va errno
89	is set to indicate the error.
90	.Sh ERRORS
91	.Fn Statfs
92	fails if one or more of the following are true:
93	.Bl -tag -width Er
94	.It Bq Er ENOTDIR
95	A component of the path prefix of
96	.Fa Path
97	is not a directory.
98	.It Bq Er ENAMETOOLONG
99	The length of a component of
100	.Fa path
101	exceeds
102	.Dv {NAME_MAX}
103	characters, or the length of
104	.Fa path
105	exceeds
106	.Dv {PATH_MAX}
107	characters.
108	.It Bq Er ENOENT
109	The file referred to by
110	.Fa path
111	does not exist.
112	.It Bq Er EACCES
113	Search permission is denied for a component of the path prefix of
114	.Fa path .
115	.It Bq Er ELOOP
116	Too many symbolic links were encountered in translating
117	.Fa path .
118	.It Bq Er EFAULT
119	.Fa Buf
120	or
121	.Fa path
122	points to an invalid address.
123	.It Bq Er EIO
124	An
125	.Tn I/O
126	error occurred while reading from or writing to the file system.
127	.El
128	.Pp
129	.Fn Fstatfs
130	fails if one or more of the following are true:
131	.Bl -tag -width Er
132	.It Bq Er EBADF
133	.Fa fd
134	is not a valid open file descriptor.
135	.It Bq Er EFAULT
136	.Fa Buf
137	points to an invalid address.
138	.It Bq Er EIO
139	An
140	.Tn I/O
141	error occurred while reading from or writing to the file system.
142	.El
143	.Sh HISTORY
144	The
145	.Fn statfs
146	function first appeared in 4.4BSD.