localeconv - return locale-specific information
#include <locale.h>
struct lconv *localeconv(void);
[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2017 defers to the ISO C standard.The localeconv() function shall set the components of an object with the type struct lconv with the values appropriate for the formatting of numeric quantities (monetary and otherwise) according to the rules of the current locale.
The members of the structure with type char * are pointers to strings, any of which (except decimal_point) can point to "", to indicate that the value is not available in the current locale or is of zero length. The members with type char are non-negative numbers, any of which can be {CHAR_MAX} to indicate that the value is not available in the current locale.
The members include the following:
- char *decimal_point
- The radix character used to format non-monetary quantities.
- char *thousands_sep
- The character used to separate groups of digits before the decimal-point character in formatted non-monetary quantities.
- char *grouping
- A string whose elements taken as one-byte integer values indicate the size of each group of digits in formatted non-monetary quantities.
- char *int_curr_symbol
- The international currency symbol applicable to the current locale. The first three characters contain the alphabetic international currency symbol in accordance with those specified in the ISO 4217:1995 standard. The fourth character (immediately preceding the null byte) is the character used to separate the international currency symbol from the monetary quantity.
- char *currency_symbol
- The local currency symbol applicable to the current locale.
- char *mon_decimal_point
- The radix character used to format monetary quantities.
- char *mon_thousands_sep
- The separator for groups of digits before the decimal-point in formatted monetary quantities.
- char *mon_grouping
- A string whose elements taken as one-byte integer values indicate the size of each group of digits in formatted monetary quantities.
- char *positive_sign
- The string used to indicate a non-negative valued formatted monetary quantity.
- char *negative_sign
- The string used to indicate a negative valued formatted monetary quantity.
- char int_frac_digits
- The number of fractional digits (those after the decimal-point) to be displayed in an internationally formatted monetary quantity.
- char frac_digits
- The number of fractional digits (those after the decimal-point) to be displayed in a formatted monetary quantity.
- char p_cs_precedes
- Set to 1 if the currency_symbol precedes the value for a non-negative formatted monetary quantity. Set to 0 if the symbol succeeds the value.
- char p_sep_by_space
- Set to a value indicating the separation of the currency_symbol, the sign string, and the value for a non-negative formatted monetary quantity.
- char n_cs_precedes
- Set to 1 if the currency_symbol precedes the value for a negative formatted monetary quantity. Set to 0 if the symbol succeeds the value.
- char n_sep_by_space
- Set to a value indicating the separation of the currency_symbol, the sign string, and the value for a negative formatted monetary quantity.
- char p_sign_posn
- Set to a value indicating the positioning of the positive_sign for a non-negative formatted monetary quantity.
- char n_sign_posn
- Set to a value indicating the positioning of the negative_sign for a negative formatted monetary quantity.
- char int_p_cs_precedes
- Set to 1 or 0 if the int_curr_symbol respectively precedes or succeeds the value for a non-negative internationally formatted monetary quantity.
- char int_n_cs_precedes
- Set to 1 or 0 if the int_curr_symbol respectively precedes or succeeds the value for a negative internationally formatted monetary quantity.
- char int_p_sep_by_space
- Set to a value indicating the separation of the int_curr_symbol, the sign string, and the value for a non-negative internationally formatted monetary quantity.
- char int_n_sep_by_space
- Set to a value indicating the separation of the int_curr_symbol, the sign string, and the value for a negative internationally formatted monetary quantity.
- char int_p_sign_posn
- Set to a value indicating the positioning of the positive_sign for a non-negative internationally formatted monetary quantity.
- char int_n_sign_posn
- Set to a value indicating the positioning of the negative_sign for a negative internationally formatted monetary quantity.
The elements of grouping and mon_grouping are interpreted according to the following:
- {CHAR_MAX}
- No further grouping is to be performed.
- 0
- The previous element is to be repeatedly used for the remainder of the digits.
- other
- The integer value is the number of digits that comprise the current group. The next element is examined to determine the size of the next group of digits before the current group.
The values of p_sep_by_space, n_sep_by_space, int_p_sep_by_space, and int_n_sep_by_space are interpreted according to the following:
- 0
- No space separates the currency symbol and value.
- 1
- If the currency symbol and sign string are adjacent, a space separates them from the value; otherwise, a space separates the currency symbol from the value.
- 2
- If the currency symbol and sign string are adjacent, a space separates them; otherwise, a space separates the sign string from the value.
For int_p_sep_by_space and int_n_sep_by_space, the fourth character of int_curr_symbol is used instead of a space.
The values of p_sign_posn, n_sign_posn, int_p_sign_posn, and int_n_sign_posn are interpreted according to the following:
- 0
- Parentheses surround the quantity and currency_symbol or int_curr_symbol.
- 1
- The sign string precedes the quantity and currency_symbol or int_curr_symbol.
- 2
- The sign string succeeds the quantity and currency_symbol or int_curr_symbol.
- 3
- The sign string immediately precedes the currency_symbol or int_curr_symbol.
- 4
- The sign string immediately succeeds the currency_symbol or int_curr_symbol.
The implementation shall behave as if no function in this volume of POSIX.1-2017 calls localeconv().
[CX] The localeconv() function need not be thread-safe.
The localeconv() function shall return a pointer to the filled-in object. The application shall not modify the structure to which the return value points, [CX] nor any storage areas pointed to by pointers within the structure. The returned pointer, and pointers within the structure, might be invalidated or the structure [CX] or the storage areas might be overwritten by a subsequent call to localeconv(). In addition, [CX] the returned pointer, and pointers within the structure, might be invalidated or the structure [CX] or the storage areas might be overwritten by subsequent calls to setlocale() with the categories LC_ALL, LC_MONETARY, or LC_NUMERIC, [CX] or by calls to uselocale() which change the categories LC_MONETARY or LC_NUMERIC. The returned pointer, pointers within the structure, the structure, and the storage areas might also be invalidated if the calling thread is terminated.
No errors are defined.
None.
The following table illustrates the rules which may be used by four countries to format monetary quantities.
Country
Positive Format
Negative Format
International Format
Italy
€.1.230
-€.1.230
EUR.1.230
Netherlands
€ 1.234,56
€ -1.234,56
EUR 1.234,56
Norway
kr1.234,56
kr1.234,56-
NOK 1.234,56
Switzerland
SFrs.1,234.56
SFrs.1,234.56C
CHF 1,234.56
For these four countries, the respective values for the monetary members of the structure returned by localeconv() are:
Italy
Netherlands
Norway
Switzerland
int_curr_symbol
"EUR."
"EUR "
"NOK "
"CHF "
currency_symbol
"€."
"€"
"kr"
"SFrs."
mon_decimal_point
""
","
","
"."
mon_thousands_sep
"."
"."
"."
","
mon_grouping
"\3"
"\3"
"\3"
"\3"
positive_sign
""
""
""
""
negative_sign
"-"
"-"
"-"
"C"
int_frac_digits
0
2
2
2
frac_digits
0
2
2
2
p_cs_precedes
1
1
1
1
p_sep_by_space
0
1
0
0
n_cs_precedes
1
1
1
1
n_sep_by_space
0
1
0
0
p_sign_posn
1
1
1
1
n_sign_posn
1
4
2
2
int_p_cs_precedes
1
1
1
1
int_n_cs_precedes
1
1
1
1
int_p_sep_by_space
0
0
0
0
int_n_sep_by_space
0
0
0
0
int_p_sign_posn
1
1
1
1
int_n_sign_posn
1
4
4
2
None.
None.
fprintf, fscanf, isalpha, isascii, nl_langinfo, setlocale, strcat, strchr, strcmp, strcoll, strcpy, strftime, strlen, strpbrk, strspn, strtok, strxfrm, strtod, uselocale
XBD <langinfo.h>, <locale.h>
First released in Issue 4. Derived from the ANSI C standard.
A note indicating that this function need not be reentrant is added to the DESCRIPTION.
The RETURN VALUE section is rewritten to avoid use of the term "must".
This reference page is updated for alignment with the ISO/IEC 9899:1999 standard.
ISO/IEC 9899:1999 standard, Technical Corrigendum 1 is incorporated.
IEEE Std 1003.1-2001/Cor 1-2002, item XSH/TC1/D6/31 is applied, removing references to int_curr_symbol and updating the descriptions of p_sep_by_space and n_sep_by_space. These changes are for alignment with the ISO C standard.
Austin Group Interpretation 1003.1-2001 #156 is applied.
The definitions of int_curr_symbol and currency_symbol are updated.
The examples in the APPLICATION USAGE section are updated.
POSIX.1-2008, Technical Corrigendum 1, XSH/TC1-2008/0362 [75] is applied.
POSIX.1-2008, Technical Corrigendum 2, XSH/TC2-2008/0200 [656] is applied.
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