xref: /original-bsd/lib/libc/sys/getfsstat.2 (revision 3705696b)
1.\" Copyright (c) 1989, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" %sccs.include.redist.roff%
5.\"
6.\"	@(#)getfsstat.2	8.1 (Berkeley) 06/09/93
7.\"
8.Dd
9.Dt GETFSSTAT 2
10.Os
11.Sh NAME
12.Nm getfsstat
13.Nd get list of all mounted filesystems
14.Sh SYNOPSIS
15.Fd #include <sys/param.h>
16.Fd #include <sys/ucred.h>
17.Fd #include <sys/mount.h>
18.Ft int
19.Fn getfsstat "struct statfs *buf" "long bufsize" "int flags"
20.Sh DESCRIPTION
21.Fn Getfsstat
22returns information about all mounted filesystems.
23.Fa Buf
24is a pointer to
25.Xr statfs
26structures defined as follows:
27.Bd -literal
28typedef quad fsid_t;
29
30#define MNAMELEN 32	/* length of buffer for returned name */
31
32struct statfs {
33    short   f_type;	/* type of filesystem (see below) */
34    short   f_flags;	/* copy of mount flags */
35    long    f_bsize;	/* fundamental filesystem block size */
36    long    f_iosize;	/* optimal transfer block size */
37    long    f_blocks;	/* total data blocks in filesystem */
38    long    f_bfree;	/* free blocks in fs */
39    long    f_bavail;	/* free blocks avail to non-superuser */
40    long    f_files;	/* total file nodes in filesystem */
41    long    f_ffree;	/* free file nodes in fs */
42    fsid_t  f_fsid;	/* filesystem id */
43    long    f_spare[6];	/* spare for later */
44    char    f_mntonname[MNAMELEN]; /* directory on which mounted */
45    char    f_mntfromname[MNAMELEN]; /* mounted filesystem */
46};
47/*
48 * File system types.
49 */
50#define	MOUNT_UFS	1
51#define	MOUNT_NFS	2
52#define	MOUNT_PC	3
53.Ed
54.Pp
55Fields that are undefined for a particular filesystem are set to -1.
56The buffer is filled with an array of
57.Fa fsstat
58structures, one for each mounted filesystem
59up to the size specified by
60.Fa bufsize .
61.Pp
62If
63.Fa buf
64is given as NULL,
65.Fn getfsstat
66returns just the number of mounted filesystems.
67.Pp
68Normally
69.Fa flags
70should be specified as
71.Dv MNT_WAIT .
72If
73.Fa flags
74is set to
75.Dv MNT_NOWAIT ,
76.Fn getfsstat
77will return the information it has available without requesting
78an update from each filesystem.
79Thus, some of the information will be out of date, but
80.Fn getfsstat
81will not block waiting for information from a filesystem that is
82unable to respond.
83.Sh RETURN VALUES
84Upon successful completion, the number of
85.Fa fsstat
86structures is returned.
87Otherwise, -1 is returned and the global variable
88.Va errno
89is set to indicate the error.
90.Sh ERRORS
91.Fn Getfsstat
92fails if one or more of the following are true:
93.Bl -tag -width Er
94.It EFAULT
95.Fa Buf
96points to an invalid address.
97.It EIO
98An
99.Tn I/O
100error occurred while reading from or writing to the filesystem.
101.El
102.Sh SEE ALSO
103.Xr statfs 2 ,
104.Xr fstab 5 ,
105.Xr mount 8
106.Sh HISTORY
107The
108.Nm getfsstat
109function first appeared in 4.4BSD.
110