freebsd-skq/lib/libutil/expand_number.3
jhb 8a39122d16 expand_number(3) parses suffixes, not prefixes.
While here, tidy the opening sentence a bit.

MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D20791
2019-07-20 16:03:54 +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
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" $FreeBSD$
.\"
.Dd July 20, 2019
.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 parses the
.Fa buf
string and stores a unsigned 64-bit quantity at
.Fa *num .
.Pp
The
.Fn expand_number
function
is case-insensitive and
follows the SI power of two convention.
.Pp
The suffixes are:
.Bl -column "Suffix" "Description" "1000000000000000000" -offset indent
.It Sy "Suffix" 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 suffix 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 .