strfmon(3C) Standard C Library Functions strfmon(3C)NAMEstrfmon - convert monetary value to string
SYNOPSIS
#include <monetary.h>
ssize_t strfmon(char *restrict s, size_t maxsize,
const char *restrict format...);
DESCRIPTION
The strfmon() function places characters into the array pointed to by s
as controlled by the string pointed to by format. No more than maxsize
bytes are placed into the array.
The format is a character string that contains two types of objects:
plain characters, which are simply copied to the output stream, and
conversion specifications, each of which results 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.
A conversion specification consists of the following sequence:
o a % character
o optional flags
o optional field width
o optional left precision
o optional right precision
o a required conversion character that determines the conver‐
sion to be performed.
Flags
One or more of the following optional flags can be specified to control
the conversion:
=f An = followed by a single character f which is used as the
numeric fill character. The fill character must be repre‐
sentable in a single byte in order to work with precision and
width counts. The default numeric fill character is the space
character. This flag does not affect field width filling
which always uses the space character. This flag is ignored
unless a left precision (see below) is specified.
^ Do not format the currency amount with grouping characters.
The default is to insert the grouping characters if defined
for the current locale.
+ or ( Specify the style of representing positive and negative cur‐
rency amounts. Only one of `+' or `(' may be specified. If
`+' is specified, the locale's equivalent of + and `−' are
used. If `(' is specified, negative amounts are enclosed
within parentheses. If neither flag is specified, the `+'
style is used.
! Suppress the currency symbol from the output conversion.
− Specify the alignment. If this flag is present all fields
are left-justified (padded to the right) rather than right-
justified.
Field Width
w A decimal digit string w specifying a minimum field width in bytes
in which the result of the conversion is right-justified (or
left-justified if the flag `−' is specified). The default is zero.
Left Precision
#n A `#' followed by a decimal digit string n 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 strfmon() aligned in the same
columns. It can also be used to fill unused positions with a spe‐
cial character as in $***123.45. This option causes an amount to
be formatted as if it has the number of digits specified by n. If
more than n digit positions are required, this conversion speci‐
fication is ignored. Digit positions in excess of those actually
required are filled with the numeric fill character (see the =f
flag above).
If grouping has not been suppressed with the `^' flag, and it is
defined for the current locale, grouping separators are inserted
before the fill characters (if any) are added. Grouping separa‐
tors are not applied to fill characters even if the fill charac‐
ter is a digit.
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 characters to make their posi‐
tive and negative formats an equal length.
Right Precision
.p A period followed by a decimal digit string p specifying the
number of digits after the radix character. If the value of the
right precision p is zero, 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.
Conversion Characters
The conversion characters and their meanings are:
i The double argument is formatted according to the locale's inter‐
national currency format (for example, in the U.S.A.: USD
1,234.56).
n The double argument is formatted according to the locale's
national currency format (for example, in the U.S.A.: $1,234.56).
% Convert to a % no argument is converted. The entire conversion
specification must be %%.
Locale Information
The LC_MONETARY 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 LC_NUMERIC
category), the grouping separator, the currency symbols and formats.
The international currency symbol should be in conformance with the ISO
4217: 1987 standard.
RETURN VALUES
If the total number of resulting bytes (including the terminating null
byte) is not more than maxsize, strfmon() returns the number of bytes
placed into the array pointed to by s, not including the terminating
null byte. Otherwise, −1 is returned, the contents of the array are
indeterminate, and errno is set to indicate the error.
ERRORS
The strfmon() function will fail if:
ENOSYS The function is not supported.
E2BIG Conversion stopped due to lack of space in the buffer.
USAGE
The behavior of strfmon() in an SUSv3-conforming application differs
from its behavior in a non-conforming application as follows:
o With the conversion 'i', strfmon() uses information set to
int_p_cs_precedes, int_n_cs_precedes, int_p_sep_by_space,
int_n_sep_by_space, int_p_sign_posn, and int_n_sign_posn of
the current locale instead of p_cs_precedes, n_cs_precedes,
p_sep_by_space, n_sep_by_space, p_sign_posn, and
n_sign_posn, respectively.
o With the conversion 'i', strfmon() uses the fourth character
of the string set to int_curr_symbol of the current locale
instead of a space forint_p_sep_by_space and
int_n_sep_by_space.
o When the value of p_sep_by_space, n_sep_by_space,
int_p_sep_by_space, or int_n_sep_by_space is set to 2 in the
current locale, strfmon() separates the currency symbol from
the sign string by a space, if adjacent; otherwise, strf‐
mon() separates the sign string from the value by a space.
EXAMPLES
Example 1 A sample output of strfmon().
Given a locale for the U.S.A. and the values 123.45, −123.45, and
3456.781:
┌────────────────────────────────────────────────────────────────────┐
│ Conversion Output Comments │
│ Specification │
├────────────────────────────────────────────────────────────────────┤
│ %n $123.45 default formatting │
│ -$123.45 │
│ $3,456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %11n $123.45 right align within an 11 │
│ -$123.45 character field │
│ $3,456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %#5n $123.45 aligned columns for values │
│ -$123.45 up to 99,999 │
│ $3,456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %=*#5n $***123.45 specify a fill character │
│ -$***123.45 │
│ $*3,456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %=0#5n $000123.45 fill characters do not use │
│ -$000123.45 grouping even if the fill │
│ $03,456.78 character is a digit │
├────────────────────────────────────────────────────────────────────┤
│ %^#5n $123.45 disable the grouping │
│ -$123.45 separator │
│ $3456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %^#5.0n $123 round off to whole units │
│ -$123 │
│ $3457 │
├────────────────────────────────────────────────────────────────────┤
│ %^#5.4n $123.4500 increase the precision │
│ -$123.4500 │
│ $3456.7810 │
├────────────────────────────────────────────────────────────────────┤
│ %(#5n 123.45 use an alternative │
│ ($123.45) pos/neg style │
│ $3,456.78 │
├────────────────────────────────────────────────────────────────────┤
│ %!(#5n 123.45 disable the currency │
│ (123.45) symbol │
│ 3,456.78 │
└────────────────────────────────────────────────────────────────────┘
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│CSI │Enabled │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Standard │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe with exceptions │
└─────────────────────────────┴─────────────────────────────┘
Th strfmon() function can be used safely in multithreaded applications,
as long as setlocale(3C) is not called to change the locale.
SEE ALSOlocaleconv(3C), setlocale(3C), attributes(5), standards(5)SunOS 5.10 24 Jan 2008 strfmon(3C)
