xref: /freebsd/lib/libc/gen/getvfsbyname.3 (revision 5965373e69ca208cedd8ede9716ef0d58e6c3434)
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32.\"     @(#)kvm_getvfsbyname.3	8.3 (Berkeley) 5/4/95
33.\" $FreeBSD$
34.\"
35.Dd May 4, 1995
36.Dt GETVFSBYNAME 3
37.Os
38.Sh NAME
39.Nm getvfsbyname
40.Nd get information about a filesystem
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In sys/param.h
45.In sys/mount.h
46.Ft int
47.Fn getvfsbyname "const char *name" "struct xvfsconf *vfc"
48.Sh DESCRIPTION
49The
50.Fn getvfsbyname
51function provides access to information about a
52filesystem module that is configured in the kernel.
53If successful,
54the requested filesystem
55.Fa xvfsconf
56is returned in the location pointed to by
57.Fa vfc .
58The fields in a
59.Dq Li struct xvfsconf
60are defined as follows:
61.Pp
62.Bl -tag -compact -width vfc_refcount
63.It vfc_name
64the name of the filesystem
65.It vfc_typenum
66the filesystem type number assigned by the kernel
67.It vfc_refcount
68the number of active mount points using the filesystem
69.It vfc_flags
70flag bits, as described below
71.El
72.Pp
73The flags are defined as follows:
74.Pp
75.Bl -tag -width VFCF_SYNTHETIC -compact
76.It Dv VFCF_STATIC
77statically compiled into kernel
78.It Dv VFCF_NETWORK
79may get data over the network
80.It Dv VFCF_READONLY
81writes are not implemented
82.It Dv VFCF_SYNTHETIC
83data does not represent real files
84.It Dv VFCF_LOOPBACK
85aliases some other mounted FS
86.It Dv VFCF_UNICODE
87stores file names as Unicode
88.El
89.Sh RETURN VALUES
90.Rv -std getvfsbyname
91.Sh ERRORS
92The following errors may be reported:
93.Bl -tag -width Er
94.It Bq Er EFAULT
95The
96.Fa vfc
97pointer contains an invalid address.
98.It Bq Er ENOENT
99The
100.Fa name
101specifies a filesystem that is unknown or not configured in the kernel.
102.El
103.Sh SEE ALSO
104.Xr mount 2 ,
105.Xr sysctl 3 ,
106.Xr mount 8 ,
107.Xr sysctl 8
108.Sh HISTORY
109A variant of the
110.Fn getvfsbyname
111function first appeared in
112.Fx 2.0 .
113