1.\" $NetBSD: humanize_number.3,v 1.4 2003/04/16 13:34:37 wiz Exp $ 2.\" $FreeBSD: /repoman/r/ncvs/src/lib/libutil/humanize_number.3,v 1.4.2.1 2004/09/28 18:24:50 pjd Exp $ 3.\" $DragonFly: src/lib/libutil/humanize_number.3,v 1.1 2004/11/05 17:05:26 dillon Exp $ 4.\" 5.\" Copyright (c) 1999, 2002 The NetBSD Foundation, Inc. 6.\" All rights reserved. 7.\" 8.\" This code is derived from software contributed to The NetBSD Foundation 9.\" by Luke Mewburn and by Tomas Svensson. 10.\" 11.\" Redistribution and use in source and binary forms, with or without 12.\" modification, are permitted provided that the following conditions 13.\" are met: 14.\" 1. Redistributions of source code must retain the above copyright 15.\" notice, this list of conditions and the following disclaimer. 16.\" 2. Redistributions in binary form must reproduce the above copyright 17.\" notice, this list of conditions and the following disclaimer in the 18.\" documentation and/or other materials provided with the distribution. 19.\" 3. All advertising materials mentioning features or use of this software 20.\" must display the following acknowledgement: 21.\" This product includes software developed by the NetBSD 22.\" Foundation, Inc. and its contributors. 23.\" 4. Neither the name of The NetBSD Foundation nor the names of its 24.\" contributors may be used to endorse or promote products derived 25.\" from this software without specific prior written permission. 26.\" 27.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37.\" POSSIBILITY OF SUCH DAMAGE. 38.\" 39.Dd May 25, 2004 40.Dt HUMANIZE_NUMBER 3 41.Os 42.Sh NAME 43.Nm humanize_number 44.Nd format a number into a human readable form 45.Sh LIBRARY 46.Lb libutil 47.Sh SYNOPSIS 48.In libutil.h 49.Ft int 50.Fo humanize_number 51.Fa "char *buf" "size_t len" "int64_t number" "const char *suffix" 52.Fa "int scale" "int flags" 53.Fc 54.Sh DESCRIPTION 55The 56.Fn humanize_number 57function formats the signed 64-bit quantity given in 58.Fa number 59into 60.Fa buffer . 61A space and then 62.Fa suffix 63is appended to the end. 64The buffer pointed to by 65.Fa buffer 66must be at least 67.Fa len 68bytes bytes long. 69.Pp 70If the formatted number (including 71.Fa suffix ) 72would be too long to fit into 73.Fa buffer , 74then divide 75.Fa number 76by 1024 until it will. 77In this case, prefix 78.Fa suffix 79with the appropriate SI designator. 80.Pp 81The prefixes are: 82.Bl -column "Prefix" "Description" "Multiplier" -offset indent 83.It Sy "Prefix" Ta Sy "Description" Ta Sy "Multiplier" 84.It Li k Ta No kilo Ta 1024 85.It Li M Ta No mega Ta 1048576 86.It Li G Ta No giga Ta 1073741824 87.It Li T Ta No tera Ta 1099511627776 88.It Li P Ta No peta Ta 1125899906842624 89.It Li E Ta No exa Ta 1152921504606846976 90.El 91.Pp 92The 93.Fa len 94argument must be at least 4 plus the length of 95.Fa suffix , 96in order to ensure a useful result is generated into 97.Fa buffer . 98To use a specific prefix, specify this as 99.Fa scale 100(multiplier = 1024 ^ scale). 101This cannot be combined with any of the 102.Fa scale 103flags below. 104.Pp 105The following flags may be passed in 106.Fa scale : 107.Bl -tag -width ".Dv HN_DIVISOR_1000" -offset indent 108.It Dv HN_AUTOSCALE 109Format the buffer using the lowest multiplier possible. 110.It Dv HN_GETSCALE 111Return the prefix index number (the number of times 112.Fa number 113must be divided to fit) instead of formatting it to the buffer. 114.El 115.Pp 116The following flags may be passed in 117.Fa flags : 118.Bl -tag -width ".Dv HN_DIVISOR_1000" -offset indent 119.It Dv HN_DECIMAL 120If the final result is less than 10, display it using one digit. 121.It Dv HN_NOSPACE 122Do not put a space between 123.Fa number 124and the prefix. 125.It Dv HN_B 126Use 127.Ql B 128(bytes) as prefix if the original result does not have a prefix. 129.It Dv HN_DIVISOR_1000 130Divide 131.Fa number 132with 1000 instead of 1024. 133.El 134.Sh RETURN VALUES 135The 136.Fn humanize_number 137function returns the number of characters stored in 138.Fa buffer 139(excluding the terminating 140.Dv NUL ) 141upon success, or \-1 upon failure. 142If 143.Dv HN_GETSCALE 144is specified, the prefix index number will be returned instead. 145.Sh HISTORY 146The 147.Fn humanize_number 148function first appeared in 149.Nx 2.0 . 150