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