libc/gen/getmntinfo.3

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.\"     @(#)getmntinfo.3	8.1 (Berkeley) 6/9/93
.\" $FreeBSD: src/lib/libc/gen/getmntinfo.3,v 1.8.2.4 2003/03/13 18:05:37 trhodes Exp $
.\"
.Dd April 1, 2011
.Dt GETMNTINFO 3
.Os
.Sh NAME
.Nm getmntinfo ,
.Nm getmntvinfo
.Nd get information about mounted file systems
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/param.h
.In sys/ucred.h
.In sys/mount.h
.Ft int
.Fn getmntinfo "struct statfs **mntbufp" "int flags"
.Ft int
.Fn getmntvinfo "struct statfs **mntbufp" "struct statvfs **mntvbufp" "int flags"
.Sh DESCRIPTION
The
.Fn getmntinfo
function
returns an array of
.Fn statfs
structures describing each currently mounted file system (see
.Xr statfs 2 ) .
.Pp
The
.Fn getmntinfo
function
passes its
.Fa flags
argument transparently to
.Xr getfsstat 2 .
.Pp
The
.Fn getmntvinfo
function
returns an array of
.Vt statfs
and
.Vt statvfs
structures describing each currently mounted file system (see
.Xr statfs 2 ) ,
and otherwise works like
.Fn getmntinfo .
.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.
.Pp
The
.Fn getmntvinfo
function
additionally stores the pointer to the
.Vt statvfs
array into
.Fa mntvbufp .
.Sh ERRORS
The
.Fn getmntinfo
and
.Fn getmntvinfo
functions may fail and set
.Va errno
for any of the errors specified for the library routines
.Xr getfsstat 2 ,
.Xr getvfsstat 2
or
.Xr malloc 3 .
.Sh SEE ALSO
.Xr getfsstat 2 ,
.Xr getvfsstat 2 ,
.Xr mount 2 ,
.Xr statfs 2 ,
.Xr mount 8
.Sh HISTORY
The
.Fn getmntinfo
function first appeared in
.Bx 4.4 .
.Pp
The
.Fn getmntvinfo
function first appeared in
.Dx 1.13 .
.Sh BUGS
The
.Fn getmntinfo
and
.Fn getmntvinfo
functions write the array of structures to an internal static object
and returns
a pointer to that object.
Subsequent calls to
.Fn getmntinfo
or
.Fn getmntvinfo
will modify the same object.
.Pp
The memory allocated by
.Fn getmntinfo
or
.Fn getmntvinfo
cannot be
.Xr free 3 Ns 'd
by the application.