1.\" $NetBSD: humanize_number.3,v 1.9 2011/01/14 10:08:57 jruoho Exp $ 2.\" 3.\" Copyright (c) 1999, 2002, 2008 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 and by Tomas Svensson. 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 January 14, 2011 31.Dt HUMANIZE_NUMBER 3 32.Os 33.Sh NAME 34.Nm dehumanize_number , 35.Nm humanize_number 36.Nd format a number into a human readable form and viceversa 37.Sh SYNOPSIS 38.In stdlib.h 39.Ft int 40.Fn dehumanize_number "const char *str" "int64_t *result" 41.Ft int 42.Fn humanize_number "char *buf" "size_t len" "int64_t number" "const char *suffix" "int scale" "int flags" 43.Sh DESCRIPTION 44The 45.Fn humanize_number 46function formats the signed 64 bit quantity given in 47.Fa number 48into 49.Fa buffer . 50A space and then 51.Fa suffix 52is appended to the end. 53.Fa buffer 54must be at least 55.Fa len 56bytes long. 57.Pp 58If the formatted number (including 59.Fa suffix ) 60would be too long to fit into 61.Fa buffer , 62then divide 63.Fa number 64by 1024 until it will. 65In this case, prefix 66.Fa suffix 67with the appropriate SI designator. 68.Pp 69The prefixes are: 70.Bl -column "Prefix" "Description" "Multiplier" -offset indent 71.It Sy "Prefix" Ta Sy "Description" Ta Sy "Multiplier" 72.It k kilo 1024 73.It M mega 1048576 74.It G giga 1073741824 75.It T tera 1099511627776 76.It P peta 1125899906842624 77.It E exa 1152921504606846976 78.El 79.Pp 80.Fa len 81must be at least 4 plus the length of 82.Fa suffix , 83in order to ensure a useful result is generated into 84.Fa buffer . 85To use a specific prefix, specify this as 86.Fa scale 87(Multiplier = 1024 ^ scale). 88This can not be combined with any of the 89.Fa scale 90flags below. 91.Pp 92The following flags may be passed in 93.Pa scale : 94.Bl -tag -width Dv -offset indent 95.It Dv HN_AUTOSCALE 96Format the buffer using the lowest multiplier possible. 97.It Dv HN_GETSCALE 98Return the prefix index number (the number of times 99.Fa number 100must be divided to fit) instead of formatting it to the buffer. 101.El 102.Pp 103The following flags may be passed in 104.Pa flags : 105.Bl -tag -width Dv -offset indent 106.It Dv HN_DECIMAL 107If the final result is less than 10, display it using one digit. 108.It Dv HN_NOSPACE 109Do not put a space between 110.Fa number 111and the prefix. 112.It Dv HN_B 113Use 'B' (bytes) as prefix if the original result does not have a prefix. 114.It Dv HN_DIVISOR_1000 115Divide 116.Fa number 117with 1000 instead of 1024. 118.El 119.Pp 120The 121.Fn dehumanize_number 122function parses the string representing an integral value given in 123.Fa str 124and stores the numerical value in the integer pointed to by 125.Fa result . 126The provided string may hold one of the suffixes, which will be interpreted 127and used to scale up its accompanying numerical value. 128.Sh RETURN VALUES 129.Fn humanize_number 130returns 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.Pp 137.Fn dehumanize_number 138returns 0 if the string was parsed correctly. 139A \-1 is returned to indicate failure and an error code is stored in 140.Va errno . 141.Sh ERRORS 142.Fn dehumanize_number 143will fail and no number will be stored in 144.Fa result 145if: 146.Bl -tag -width Er 147.It Bq Er EINVAL 148The string in 149.Fa str 150was empty or carried an unknown suffix. 151.It Bq Er ERANGE 152The string in 153.Fa str 154represented a number that does not fit in 155.Fa result . 156.El 157.Sh SEE ALSO 158.Xr strsuftoll 3 , 159.Xr orders 7 , 160.Xr humanize_number 9 161.Sh HISTORY 162.Fn humanize_number 163first appeared in 164.Nx 2.0 . 165.Pp 166.Fn dehumanize_number 167first appeared in 168.Nx 5.0 . 169