gen/FreeBSD/getmntinfo.3

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  28 .\"     @(#)getmntinfo.3        8.1 (Berkeley) 6/9/93
  29 .\" $FreeBSD: src/lib/libc/gen/getmntinfo.3,v 1.13 2007/01/09 00:27:54 imp Exp $
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  31 .Dd May 4, 2010
  32 .Dt GETMNTINFO 3
  33 .Os
  34 .Sh NAME
  35 .Nm getmntinfo
  36 .Nm getmntinfo64
  37 .Nd get information about mounted file systems
  38 .Sh SYNOPSIS
  39 .In sys/param.h
  40 .In sys/ucred.h
  41 .In sys/mount.h
  42 .Ft int
  43 .Fn getmntinfo "struct statfs **mntbufp" "int flags"
  44 .Sh TRANSITIIONAL SYNOPSIS (NOW DEPRECATED)
  45 .Ft int
  46 .br
  47 .Fn getmntinfo64 "struct statfs64 **mntbufp" "int flags" ;
  48 .Sh DESCRIPTION
  49 The
  50 .Fn getmntinfo
  51 function
  52 returns an array of
  53 .Ft statfs
  54 structures describing each currently mounted file system (see
  55 .Xr statfs 2 ) .
  56 As
  57 .Xr statfs 2
  58 indicates, the structure is defined differently depending on
  59 whether the macro _DARWIN_FEATURE_64_BIT_INODE is defined (see
  60 .Xr stat 2
  61 for more information on this macro).
  62 .Pp
  63 The
  64 .Fn getmntinfo
  65 function
  66 passes its
  67 .Fa flags
  68 argument transparently to
  69 .Xr getfsstat 2 .
  70 .Sh RETURN VALUES
  71 On successful completion,
  72 .Fn getmntinfo
  73 returns a count of the number of elements in the array.
  74 The pointer to the array is stored into
  75 .Fa mntbufp .
  76 .Pp
  77 If an error occurs, zero is returned and the external variable
  78 .Va errno
  79 is set to indicate the error.
  80 Although the pointer
  81 .Fa mntbufp
  82 will be unmodified, any information previously returned by
  83 .Fn getmntinfo
  84 will be lost.
  85 .Sh ERRORS
  86 The
  87 .Fn getmntinfo
  88 function
  89 may fail and set errno for any of the errors specified for the library
  90 routines
  91 .Xr getfsstat 2
  92 or
  93 .Xr malloc 3 .
  94 .Sh TRANSITIONAL DESCRIPTION (NOW DEPRECATED)
  95 The
  96 .Fn getmntinfo64
  97 routine is equivalent to its corresponding non-64-suffixed routine,
  98 when 64-bit inodes are in effect.
  99 It was added before there was support for the symbol variants, and so is
 100 now deprecated.
 101 Instead of using it, set the
 102 .Dv _DARWIN_USE_64_BIT_INODE
 103 macro before including header files to force 64-bit inode support.
 104 .Pp
 105 The
 106 .Ft statfs64
 107 structure used by this deprecated routine is the same as the
 108 .Ft statfs
 109 structure when 64-bit inodes are in effect.
 110 .Sh SEE ALSO
 111 .Xr getfsstat 2 ,
 112 .Xr mount 2 ,
 113 .Xr stat 2 ,
 114 .Xr statfs 2 ,
 115 .Xr mount 8
 116 .Sh HISTORY
 117 The
 118 .Fn getmntinfo
 119 function first appeared in
 120 .Bx 4.4 .
 121 .Sh BUGS
 122 The
 123 .Fn getmntinfo
 124 function writes the array of structures to an internal static object
 125 and returns
 126 a pointer to that object.
 127 Subsequent calls to
 128 .Fn getmntinfo
 129 will modify the same object.
 130 .Pp
 131 The memory allocated by
 132 .Fn getmntinfo
 133 cannot be
 134 .Xr free 3 Ns 'd
 135 by the application.