1.\" $NetBSD: getbsize.3,v 1.2 1995/02/25 13:41:31 cgd Exp $ 2.\" 3.\" Copyright (c) 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)getbsize.3 8.1 (Berkeley) 6/4/93 35.\" 36.Dd June 4, 1993 37.Dt GETBSIZE 3 38.Os BSD 4.4 39.Sh NAME 40.Nm getbsize 41.Nd get user block size 42.Sh SYNOPSIS 43.Fd #include <stdlib.h> 44.Ft char * 45.Fn getbsize "int *headerlenp" "long *blocksizep" 46.Sh DESCRIPTION 47The 48.Nm getbsize 49function determines the user's preferred block size based on the value of the 50.Dq BLOCKSIZE 51environment variable; see 52.Xr environ 7 53for details on its use and format. 54.Pp 55The 56.Nm getbsize 57function returns a pointer to a null-terminated string describing 58the block size, something like 59.Dq 1K-blocks . 60The memory referenced by 61.Fa headerlenp 62is filled in with the length of the string (not including the 63terminating null). 64The memory referenced by 65.Fa blocksizep 66is filled in with block size, in bytes. 67.Pp 68If the user's block size is unreasonable, a warning message is 69written to standard error and the returned information reflects 70a block size of 512 bytes. 71.Sh SEE ALSO 72.Xr df 1 , 73.Xr du 1 , 74.Xr ls 1 , 75.Xr systat 1 , 76.Xr environ 7 77.Sh HISTORY 78The 79.Nm getbsize 80function first appeared in 81.Bx 4.4 . 82