.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "STRFMON" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" strfmon 
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.SH NAME
strfmon \- convert monetary value to a string
.SH SYNOPSIS
.LP
\fB#include <monetary.h>
.br
.sp
ssize_t strfmon(char *restrict\fP \fIs\fP\fB, size_t\fP \fImaxsize\fP\fB,
.br
\ \ \ \ \ \  const char *restrict\fP \fIformat\fP\fB, ...); \fP
\fB
.br
\fP
.SH DESCRIPTION
.LP
The \fIstrfmon\fP() function shall place characters into the array
pointed to by \fIs\fP as controlled by the string pointed
to by \fIformat\fP. No more than \fImaxsize\fP bytes are placed into
the array.
.LP
The format is a character string, beginning and ending in its initial
state, if any, that contains two types of objects:
\fIplain characters\fP, which are simply copied to the output stream,
and \fIconversion specifications\fP, each of which shall
result in the fetching of zero or more arguments which are converted
and formatted. The results are undefined if there are
insufficient arguments for the format. If the format is exhausted
while arguments remain, the excess arguments are simply
ignored.
.LP
The application shall ensure that a conversion specification consists
of the following sequence:
.IP " *" 3
A \fB'%'\fP character
.LP
.IP " *" 3
Optional flags
.LP
.IP " *" 3
Optional field width
.LP
.IP " *" 3
Optional left precision
.LP
.IP " *" 3
Optional right precision
.LP
.IP " *" 3
A required conversion specifier character that determines the conversion
to be performed
.LP
.SS Flags
.LP
One or more of the following optional flags can be specified to control
the conversion:
.TP 7
\fB=\fP\fIf\fP
An \fB'='\fP followed by a single character \fIf\fP which is used
as the numeric fill character. In order to work with
precision or width counts, the fill character shall be a single byte
character; if not, the behavior is undefined. The default
numeric fill character is the <space>. This flag does not affect field
width filling which always uses the <space>.
This flag is ignored unless a left precision (see below) is specified.
.TP 7
\fB^\fP
Do not format the currency amount with grouping characters. The default
is to insert the grouping characters if defined for the
current locale.
.TP 7
\fB+\fP\ or\ \fB(\fP
Specify the style of representing positive and negative currency amounts.
Only one of \fB'+'\fP or \fB'('\fP may be
specified. If \fB'+'\fP is specified, the locale's equivalent of \fB'+'\fP
and \fB'-'\fP are used (for example, in the
U.S., the empty string if positive and \fB'-'\fP if negative). If
\fB'('\fP is specified, negative amounts are enclosed
within parentheses. If neither flag is specified, the \fB'+'\fP style
is used.
.TP 7
\fB!\fP
Suppress the currency symbol from the output conversion.
.TP 7
\fB-\fP
Specify the alignment. If this flag is present the result of the conversion
is left-justified (padded to the right) rather than
right-justified. This flag shall be ignored unless a field width (see
below) is specified.
.sp
.SS Field Width
.TP 7
\fIw\fP
A decimal digit string \fIw\fP specifying a minimum field width in
bytes in which the result of the conversion is
right-justified (or left-justified if the flag \fB'-'\fP is specified).
The default is 0.
.sp
.SS Left Precision
.TP 7
\fB#\fP\fIn\fP
A \fB'#'\fP followed by a decimal digit string \fIn\fP specifying
a maximum number of digits expected to be formatted to
the left of the radix character. This option can be used to keep the
formatted output from multiple calls to the \fIstrfmon\fP()
function aligned in the same columns. It can also be used to fill
unused positions with a special character as in
\fB"$***123.45"\fP . This option causes an amount to be formatted
as if it has the number of digits specified by \fIn\fP. If
more than \fIn\fP digit positions are required, this conversion specification
is ignored. Digit positions in excess of those
actually required are filled with the numeric fill character (see
the \fB=\fP\fIf\fP flag above). 
.LP
If grouping has not been suppressed with the \fB'^'\fP flag, and it
is defined for the current locale, grouping separators
are inserted before the fill characters (if any) are added. Grouping
separators are not applied to fill characters even if the fill
character is a digit.
.LP
To ensure alignment, any characters appearing before or after the
number in the formatted output such as currency or sign
symbols are padded as necessary with <space>s to make their positive
and negative formats an equal length.
.sp
.SS Right Precision
.TP 7
\fB\&.\fP\fIp\fP
A period followed by a decimal digit string \fIp\fP specifying the
number of digits after the radix character. If the value of
the right precision \fIp\fP is 0, no radix character appears. If a
right precision is not included, a default specified by the
current locale is used. The amount being formatted is rounded to the
specified number of digits prior to formatting.
.sp
.SS Conversion Specifier Characters
.LP
The conversion specifier characters and their meanings are:
.TP 7
\fBi\fP
The \fBdouble\fP argument is formatted according to the locale's international
currency format (for example, in the U.S.: USD
1,234.56). If the argument is \(+-Inf or NaN, the result of the conversion
is unspecified.
.TP 7
\fBn\fP
The \fBdouble\fP argument is formatted according to the locale's national
currency format (for example, in the U.S.:
$1,234.56). If the argument is \(+-Inf or NaN, the result of the conversion
is unspecified.
.TP 7
\fB%\fP
Convert to a \fB'%'\fP ; no argument is converted. The entire conversion
specification shall be \fB%%\fP .
.sp
.SS Locale Information
.LP
The \fILC_MONETARY\fP category of the program's locale affects the
behavior of this function including the monetary radix
character (which may be different from the numeric radix character
affected by the \fILC_NUMERIC\fP category), the grouping
separator, the currency symbols, and formats. The international currency
symbol should be conformant with the ISO\ 4217:1995
standard.
.LP
If the value of \fImaxsize\fP is greater than {SSIZE_MAX}, the result
is implementation-defined.
.SH RETURN VALUE
.LP
If the total number of resulting bytes including the terminating null
byte is not more than \fImaxsize\fP, \fIstrfmon\fP()
shall return the number of bytes placed into the array pointed to
by \fIs\fP, not including the terminating null byte. Otherwise,
-1 shall be returned, the contents of the array are unspecified, and
\fIerrno\fP shall be set to indicate the error.
.SH ERRORS
.LP
The \fIstrfmon\fP() function shall fail if:
.TP 7
.B E2BIG
Conversion stopped due to lack of space in the buffer.
.sp
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
Given a locale for the U.S. and the values 123.45, -123.45, and 3456.781,
the following output might be produced. Square
brackets ( \fB"[]"\fP ) are used in this example to delimit the output.
.sp
.RS
.nf

\fB%n         [$123.45]        \fP Default formatting 
\fB           [-$123.45]
           [$3,456.78]
.sp

%11n       [    $123.45]    \fP Right align within an 11-character field 
\fB           [   -$123.45]
           [  $3,456.78]
.sp

%#5n       [ $   123.45]    \fP Aligned columns for values up to 99999 
\fB           [-$   123.45]
           [ $ 3,456.78]
.sp

%=*#5n     [ $***123.45]    \fP Specify a fill character 
\fB           [-$***123.45]
           [ $*3,456.78]
.sp

%=0#5n     [ $000123.45]    \fP Fill characters do not use grouping 
\fB           [-$000123.45]    \fP even if the fill character is a digit 
\fB           [ $03,456.78]
.sp

%^#5n      [ $  123.45]     \fP Disable the grouping separator 
\fB           [-$  123.45]
           [ $ 3456.78]
.sp

%^#5.0n    [ $  123]        \fP Round off to whole units 
\fB           [-$  123]
           [ $ 3457]
.sp

%^#5.4n    [ $  123.4500]   \fP Increase the precision 
\fB           [-$  123.4500]
           [ $ 3456.7810]
.sp

%(#5n      [$   123.45]     \fP Use an alternative pos/neg style 
\fB           [($   123.45)]
           [$ 3,456.78]
.sp

%!(#5n     [   123.45]      \fP Disable the currency symbol 
\fB           [(   123.45)]
           [ 3,456.78]
.sp

%-14#5.4n  [ $   123.4500 ] \fP Left-justify the output 
\fB           [-$   123.4500 ]
           [ $ 3,456.7810 ]
.sp

%14#5.4n   [  $   123.4500] \fP Corresponding right-justified output 
\fB           [ -$   123.4500]
           [  $ 3,456.7810]
\fP
.fi
.RE
.LP
See also the EXAMPLES section in \fIfprintf\fP().
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
Lowercase conversion characters are reserved for future standards
use and uppercase for implementation-defined use.
.SH SEE ALSO
.LP
\fIfprintf\fP(), \fIlocaleconv\fP(), the Base Definitions volume
of
IEEE\ Std\ 1003.1-2001, \fI<monetary.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .