xref: /freebsd/lib/libc/gen/getvfsbyname.3 (revision 2b743a9e9ddc6736208dc8ca1ce06ce64ad20a19)
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28.\"     @(#)kvm_getvfsbyname.3	8.3 (Berkeley) 5/4/95
29.\" $FreeBSD$
30.\"
31.Dd May 4, 1995
32.Dt GETVFSBYNAME 3
33.Os
34.Sh NAME
35.Nm getvfsbyname
36.Nd get information about a file system
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In sys/param.h
41.In sys/mount.h
42.Ft int
43.Fn getvfsbyname "const char *name" "struct xvfsconf *vfc"
44.Sh DESCRIPTION
45The
46.Fn getvfsbyname
47function provides access to information about a
48file system module that is configured in the kernel.
49If successful,
50the requested file system
51.Fa xvfsconf
52is returned in the location pointed to by
53.Fa vfc .
54The fields in a
55.Dq Li struct xvfsconf
56are defined as follows:
57.Pp
58.Bl -tag -compact -width vfc_refcount
59.It vfc_name
60the name of the file system
61.It vfc_typenum
62the file system type number assigned by the kernel
63.It vfc_refcount
64the number of active mount points using the file system
65.It vfc_flags
66flag bits, as described below
67.El
68.Pp
69The flags are defined as follows:
70.Pp
71.Bl -tag -width VFCF_SYNTHETIC -compact
72.It Dv VFCF_STATIC
73statically compiled into kernel
74.It Dv VFCF_NETWORK
75may get data over the network
76.It Dv VFCF_READONLY
77writes are not implemented
78.It Dv VFCF_SYNTHETIC
79data does not represent real files
80.It Dv VFCF_LOOPBACK
81aliases some other mounted FS
82.It Dv VFCF_UNICODE
83stores file names as Unicode
84.El
85.Sh RETURN VALUES
86.Rv -std getvfsbyname
87.Sh ERRORS
88The following errors may be reported:
89.Bl -tag -width Er
90.It Bq Er EFAULT
91The
92.Fa vfc
93argument
94points to an invalid address.
95.It Bq Er ENOENT
96The
97.Fa name
98argument
99specifies a file system that is unknown or not configured in the kernel.
100.El
101.Sh SEE ALSO
102.Xr mount 2 ,
103.Xr sysctl 3 ,
104.Xr mount 8 ,
105.Xr sysctl 8
106.Sh HISTORY
107A variant of the
108.Fn getvfsbyname
109function first appeared in
110.Fx 2.0 .
111