[apple/libc.git] / gen / FreeBSD / getbsize.3

.\" Copyright (c) 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)getbsize.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/getbsize.3,v 1.11 2007/01/09 00:27:53 imp Exp $
.\"
.Dd June 4, 1993
.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
.Fn 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
.Fn getbsize
function returns a pointer to a null-terminated string describing
the block size, something like
.Dq 1K-blocks .
The memory referenced by
.Fa headerlenp
is filled in with the length of the string (not including the
terminating 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
.Fn getbsize
function first appeared in
.Bx 4.4 .
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
e9ce8d39 A	12	.\" 4. Neither the name of the University nor the names of its contributors
	13	.\" may be used to endorse or promote products derived from this software
	14	.\" without specific prior written permission.
	15	.\"
	16	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	17	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	18	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	19	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	20	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	21	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	22	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	23	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	24	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	25	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	26	.\" SUCH DAMAGE.
	27	.\"
5b2abdfb	28	.\" @(#)getbsize.3 8.1 (Berkeley) 6/4/93
1f2f436a	29	.\" $FreeBSD: src/lib/libc/gen/getbsize.3,v 1.11 2007/01/09 00:27:53 imp Exp $
e9ce8d39	30	.\"
5b2abdfb A	31	.Dd June 4, 1993
5b2abdfb A	32	.Dt GETBSIZE 3
e9ce8d39 A	33	.Os
e9ce8d39 A	34	.Sh NAME
5b2abdfb A	35	.Nm getbsize
5b2abdfb A	36	.Nd get user block size
e9ce8d39 A	37	.Sh LIBRARY
	38	.Lb libc
	39	.Sh SYNOPSIS
5b2abdfb A	40	.In stdlib.h
	41	.Ft char *
	42	.Fn getbsize "int headerlenp" "long blocksizep"
e9ce8d39 A	43	.Sh DESCRIPTION
e9ce8d39 A	44	The
5b2abdfb A	45	.Fn getbsize
	46	function determines the user's preferred block size based on the value of the
	47	.Dq BLOCKSIZE
	48	environment variable; see
	49	.Xr environ 7
	50	for details on its use and format.
	51	.Pp
e9ce8d39	52	The
5b2abdfb A	53	.Fn getbsize
	54	function returns a pointer to a null-terminated string describing
	55	the block size, something like
	56	.Dq 1K-blocks .
	57	The memory referenced by
	58	.Fa headerlenp
	59	is filled in with the length of the string (not including the
	60	terminating null).
	61	The memory referenced by
	62	.Fa blocksizep
	63	is filled in with block size, in bytes.
	64	.Pp
	65	If the user's block size is unreasonable, a warning message is
	66	written to standard error and the returned information reflects
	67	a block size of 512 bytes.
e9ce8d39	68	.Sh SEE ALSO
5b2abdfb A	69	.Xr df 1 ,
	70	.Xr du 1 ,
	71	.Xr ls 1 ,
	72	.Xr systat 1 ,
	73	.Xr environ 7
e9ce8d39 A	74	.Sh HISTORY
e9ce8d39 A	75	The
5b2abdfb	76	.Fn getbsize
e9ce8d39 A	77	function first appeared in
e9ce8d39 A	78	.Bx 4.4 .