1.\" $NetBSD: humanize_number.9,v 1.9 2010/08/07 16:41:34 jruoho Exp $ 2.\" 3.\" Copyright (c) 1999 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Luke Mewburn. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd November 3, 2010 31.Dt HUMANIZE_UNSIGNED 3 32.Os 33.Sh NAME 34.Nm humanize_unsigned , 35.Nm format_bytes 36.Nd human readable numbers 37.Sh LIBRARY 38.Lb libutil 39.Sh SYNOPSIS 40.In sys/types.h 41.In libutil.h 42.Ft int 43.Fn humanize_unsigned \ 44"char *buf" "size_t len" "uint64_t number" "const char *suffix" "int divisor" 45.Ft int 46.Fn format_bytes "char *buf" "size_t len" "uint64_t number" 47.Sh DESCRIPTION 48The 49.Fn humanize_unsigned 50function formats the unsigned 64-bit quantity given in 51.Fa number 52into 53.Fa buf . 54A space and then 55.Fa suffix 56is appended to the end. 57The supplied 58.Fa buf 59must be at least 60.Fa len 61bytes long. 62.Pp 63If the formatted number (including 64.Fa suffix ) 65is too long to fit into 66.Fa buf , 67.Fn humanize_unsigned 68divides 69.Fa number 70by 71.Fa divisor 72until it will fit. 73In this case, 74.Fa suffix 75is prefixed with the appropriate SI designator. 76Suitable values of 77.Fa divisor 78are 1024 or 1000 to remain consistent with the common meanings of the 79SI designator prefixes. 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 k kilo 1024 85.It M mega 1048576 86.It G giga 1073741824 87.It T tera 1099511627776 88.It P peta 1125899906842624 89.It E exa 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 in 97.Fa buf . 98.Pp 99The 100.Fn format_bytes 101function 102is a front-end to 103.Fn humanize_unsigned . 104It calls the latter with a 105.Fa suffix 106of 107.Dq B . 108Also, if the suffix in the returned 109.Fa buf 110would not have a prefix, the suffix is removed. 111This means that a result of 112.Dq 100000 113occurs, instead of 114.Dq 100000 B . 115.Sh RETURN VALUES 116Both functions return the number of characters stored in 117.Fa buf 118(excluding the terminating NUL) upon success, or \-1 upon failure. 119.Sh SEE ALSO 120.Xr humanize_number 3 121.Sh HISTORY 122These functions first appeared in 123.Nx 1.5 124and were later ported to 125.Dx 2.9 . 126