NetBSD/lib/libc/gen/getbsize.3

.\"	$NetBSD: getbsize.3,v 1.9 2003/08/07 16:42:48 agc Exp $
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.\"     @(#)getbsize.3	8.1 (Berkeley) 6/4/93
.\"
.Dd May 30, 2003
.Dt GETBSIZE 3
.Os
.Sh NAME
.Nm getbsize
.Nd get user block size
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft char *
.Fn getbsize "int *headerlenp" "long *blocksizep"
.Sh DESCRIPTION
The
.Nm getbsize
function determines the user's preferred block size based on the value of the
.Dq BLOCKSIZE
environment variable; see
.Xr environ 7
for details on its use and format.
.Pp
The
.Nm getbsize
function returns a pointer to a
.Dv NUL
terminated string describing
the block size, something like
.Dq 1K-blocks .
If the
.Fa headerlenp
parameter is not
.Dv NULL
the memory referenced by
.Fa headerlenp
is filled in with the length of the string (not including the
terminating
.Dv NUL ) .
If the
.Fa blocksizep
parameter is not
.Dv NULL
the memory referenced by
.Fa blocksizep
is filled in with block size, in bytes.
.Pp
If the user's block size is unreasonable, a warning message is
written to standard error and the returned information reflects
a block size of 512 bytes.
.Sh SEE ALSO
.Xr df 1 ,
.Xr du 1 ,
.Xr ls 1 ,
.Xr systat 1 ,
.Xr environ 7
.Sh HISTORY
The
.Nm getbsize
function first appeared in
.Bx 4.4 .