freebsd-skq/lib/libutil/expand_number.3
des 3338010b29 Further simplify the code, and update the manpage.
Submitted by:	Christoph Mallon <christoph.mallon@gmx.de>
2010-08-15 18:32:06 +00:00

87 lines
2.6 KiB
Groff

.\" Copyright (c) 2007 Eric Anderson <anderson@FreeBSD.org>
.\" Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
.\" 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.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
.\"
.\" $FreeBSD$
.\"
.Dd August 15, 2010
.Dt EXPAND_NUMBER 3
.Os
.Sh NAME
.Nm expand_number
.Nd format a number from human readable form
.Sh LIBRARY
.Lb libutil
.Sh SYNOPSIS
.In libutil.h
.Ft int
.Fo expand_number
.Fa "const char *buf" "uint64_t *num"
.Fc
.Sh DESCRIPTION
The
.Fn expand_number
function unformats the
.Fa buf
string and stores a unsigned 64-bit quantity at address pointed out by the
.Fa num
argument.
.Pp
The
.Fn expand_number
function
follows the SI power of two convention.
.Pp
The prefixes are:
.Bl -column "Prefix" "Description" "1000000000000000000" -offset indent
.It Sy "Prefix" Ta Sy "Description" Ta Sy "Multiplier"
.It Li k Ta No kilo Ta 1024
.It Li M Ta No mega Ta 1048576
.It Li G Ta No giga Ta 1073741824
.It Li T Ta No tera Ta 1099511627776
.It Li P Ta No peta Ta 1125899906842624
.It Li E Ta No exa Ta 1152921504606846976
.El
.Sh RETURN VALUES
.Rv -std
.Sh ERRORS
The
.Fn expand_number
function will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The given string contains no digits.
.It Bq Er EINVAL
An unrecognized prefix was given.
.It Bq Er ERANGE
Result doesn't fit into 64 bits.
.El
.Sh SEE ALSO
.Xr humanize_number 3
.Sh HISTORY
The
.Fn expand_number
function first appeared in
.Fx 6.3 .