xref: /freebsd/lib/libc/stdlib/strfmon.3 (revision 9729f076e4d93c5a37e78d427bfe0f1ab99bbcc6)
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25.\" $FreeBSD$
26.\"
27.Dd October 26, 2022
28.Dt STRFMON 3
29.Os
30.Sh NAME
31.Nm strfmon
32.Nd convert monetary value to string
33.Sh LIBRARY
34.Lb libc
35.Sh SYNOPSIS
36.In monetary.h
37.Ft ssize_t
38.Fn strfmon "char * restrict s" "size_t maxsize" "const char * restrict format" "..."
39.Ft ssize_t
40.Fn strfmon_l "char * restrict s" "size_t maxsize" "locale_t loc" "const char * restrict format" "..."
41.Sh DESCRIPTION
42The
43.Fn strfmon
44function places characters into the array pointed to by
45.Fa s
46as controlled by the string pointed to by
47.Fa format .
48No more than
49.Fa maxsize
50bytes are placed into the array.
51.Pp
52The
53.Fn strfmon_l
54function does the same as
55.Fn strfmon
56but takes an explicit locale rather than using the current locale.
57.Pp
58The format string is composed of zero or more directives:
59ordinary characters (not
60.Cm % ) ,
61which are copied unchanged to the output stream; and conversion
62specifications, each of which results in fetching zero or more subsequent
63arguments.
64Each conversion specification is introduced by the
65.Cm %
66character.
67After the
68.Cm % ,
69the following appear in sequence:
70.Bl -bullet
71.It
72Zero or more of the following flags:
73.Bl -tag -width "XXX"
74.It Cm = Ns Ar f
75A
76.Sq Cm =
77character followed by another character
78.Ar f
79which is used as the numeric fill character.
80.It Cm ^
81Do not use grouping characters, regardless of the current locale default.
82.It Cm +
83Represent positive values by prefixing them with a positive sign,
84and negative values by prefixing them with a negative sign.
85This is the default.
86.It Cm \&(
87Enclose negative values in parentheses.
88.It Cm \&!
89Do not include a currency symbol in the output.
90.It Cm \-
91Left justify the result.
92Only valid when a field width is specified.
93.El
94.It
95An optional minimum field width as a decimal number.
96By default, there is no minimum width.
97.It
98A
99.Sq Cm #
100sign followed by a decimal number specifying the maximum
101expected number of digits before the radix character.
102When this option is used, values that do not exceed the
103specified number of digits are formatted so they will be
104correctly aligned with other values printed using the same
105format.
106This includes always leaving space for a possible sign
107indicator, even if none is needed for a particular value.
108.It
109A
110.Sq Cm \&.
111character followed by a decimal number specifying the number
112of digits after the radix character.
113.It
114One of the following conversion specifiers:
115.Bl -tag -width "XXX"
116.It Cm i
117The
118.Vt double
119argument is formatted as an international monetary amount.
120.It Cm n
121The
122.Vt double
123argument is formatted as a national monetary amount.
124.It Cm %
125A
126.Sq Li %
127character is written.
128.El
129.El
130.Sh RETURN VALUES
131If the total number of resulting bytes including the terminating
132.Dv NUL
133byte is not more than
134.Fa maxsize ,
135.Fn strfmon
136returns the number of bytes placed into the array pointed to by
137.Fa s ,
138not including the terminating
139.Dv NUL
140byte.
141Otherwise, \-1 is returned,
142the contents of the array are indeterminate,
143and
144.Va errno
145is set to indicate the error.
146.Pp
147The
148.Fn strfmon_l
149function returns the same values as
150.Fn strfmon .
151.Sh ERRORS
152The
153.Fn strfmon
154function will fail if:
155.Bl -tag -width Er
156.It Bq Er E2BIG
157Conversion stopped due to lack of space in the buffer.
158.It Bq Er EINVAL
159The format string is invalid.
160.It Bq Er ENOMEM
161Not enough memory for temporary buffers.
162.El
163.Sh SEE ALSO
164.Xr localeconv 3
165.Sh STANDARDS
166The
167.Fn strfmon
168function
169conforms to
170.St -p1003.1-2001 .
171The
172.Fn strfmon_l
173function conforms to
174.St -p1003.1-2008 .
175.Sh AUTHORS
176.An -nosplit
177The
178.Fn strfmon
179function was implemented by
180.An Alexey Zelkin Aq Mt phantom@FreeBSD.org .
181.Pp
182This manual page was written by
183.An Jeroen Ruigrok van der Werven Aq Mt asmodai@FreeBSD.org
184based on the standards' text.
185.Sh BUGS
186The
187.Fn strfmon
188function does not correctly handle multibyte characters in the
189.Fa format
190argument.
191