NAME

wcscoll, wcscoll_l - wide-character string comparison using collating information

SYNOPSIS

#include <wchar.h>

int wcscoll(const wchar_t *ws1, const wchar_t *ws2);


[CX] int wcscoll_l(const wchar_t *ws1, const wchar_t *ws2,
       locale_t locale);

DESCRIPTION

For wcscoll(): ^[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 wcscoll() ^[CX]  and wcscoll_l()  functions shall compare the wide-character string pointed to by ws1 to the wide-character string pointed to by ws2, both interpreted as appropriate to the LC_COLLATE category of the current locale, ^[CX]  or the locale represented by locale,  respectively.

The wcscoll() ^[CX]  and wcscoll_l()  functions shall not change the setting of errno if successful.

An application wishing to check for error situations should set errno to 0 before calling wcscoll() ^[CX]  or wcscoll_l().  If errno is non-zero on return, an error has occurred.

^[CX] The behavior is undefined if the locale argument to wcscoll_l() is the special locale object LC_GLOBAL_LOCALE or is not a valid locale object handle.

RETURN VALUE

Upon successful completion, wcscoll() ^[CX]  and wcscoll_l()  shall return an integer greater than, equal to, or less than 0, according to whether the wide-character string pointed to by ws1 is greater than, equal to, or less than the wide-character string pointed to by ws2, when both are interpreted as appropriate to the current locale, ^[CX]  or to the locale represented by locale,  respectively. On error, wcscoll() ^[CX]  and wcscoll_l()  shall set errno, but no return value is reserved to indicate an error.

ERRORS

These functions may fail if:

[EINVAL]

^[CX] The ws1 or ws2 arguments contain wide-character codes outside the domain of the collating sequence.

EXAMPLES

None.

APPLICATION USAGE

The wcsxfrm() and wcscmp() functions should be used for sorting large lists.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

wcscmp, wcsxfrm

XBD <wchar.h>

CHANGE HISTORY

First released in Issue 4. Derived from the MSE working draft.

Issue 5

Moved from ENHANCED I18N to BASE and the [ENOSYS] error is removed.

The DESCRIPTION is updated to indicate that errno is not changed if the function is successful.

Issue 7

The wcscoll_l() function is added from The Open Group Technical Standard, 2006, Extended API Set Part 4.

POSIX.1-2008, Technical Corrigendum 1, XSH/TC1-2008/0719 [302], XSH/TC1-2008/0720 [283], and XSH/TC1-2008/0721 [283] are applied.