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.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 .